Drop support for ruby 2.4 from ruby/spec

145 files changed, 2228 insertions, 3232 deletions

diff --git a/.travis.yml b/.travis.yml
index e26fe1dc16..1bd1ce8885 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -360,17 +360,17 @@ env:
         -Wunused-variable'
       - LDFLAGS=-Wno-unused-command-line-argument
 
-  - &rubyspec24
-    name: Check ruby/spec version guards on Ruby 2.4
+  - &rubyspec25
+    name: Check ruby/spec version guards on Ruby 2.5
     language: ruby
-    rvm: 2.4.9
+    rvm: 2.5.7
     before_install:
     install:
     before_script: chmod -R u+w spec/ruby
     # -j randomly hangs.
     script: ruby -C spec/ruby ../mspec/bin/mspec .
     after_failure:
-      - echo "ruby/spec failed on Ruby 2.4. This is likely because of a missing ruby_version_is guard, please add it. See spec/README.md."
+      - echo "ruby/spec failed on Ruby 2.5. This is likely because of a missing ruby_version_is guard, please add it. See spec/README.md."
 
   - &rubyspec27
     name: Check ruby/spec version guards on Ruby 2.7
@@ -435,7 +435,7 @@ matrix:
     - <<: *pedanticism
     - <<: *assertions
     - <<: *baseruby
-    - <<: *rubyspec24
+    - <<: *rubyspec25
     - <<: *rubyspec27
     - <<: *dependency
     # Build every commit (Allowed Failures):
diff --git a/spec/mspec/README.md b/spec/mspec/README.md
index e6fe44c6a2..86ee369e46 100644
--- a/spec/mspec/README.md
+++ b/spec/mspec/README.md
@@ -38,7 +38,7 @@ specs in a manner compatible with multiple Ruby implementations.
 
 ## Requirements
 
-MSpec requires Ruby 2.4 or more recent.
+MSpec requires Ruby 2.5 or more recent.
 
 ## Bundler
 
diff --git a/spec/mspec/lib/mspec/utils/script.rb b/spec/mspec/lib/mspec/utils/script.rb
index ec841db2e7..e8f581ef06 100644
--- a/spec/mspec/lib/mspec/utils/script.rb
+++ b/spec/mspec/lib/mspec/utils/script.rb
@@ -39,8 +39,8 @@ class MSpecScript
   end
 
   def initialize
-    ruby_version_is ""..."2.4" do
-      abort "MSpec needs Ruby 2.4 or more recent"
+    ruby_version_is ""..."2.5" do
+      abort "MSpec needs Ruby 2.5 or more recent"
     end
 
     config[:formatter] = nil
diff --git a/spec/mspec/lib/mspec/utils/warnings.rb b/spec/mspec/lib/mspec/utils/warnings.rb
index fa05c8c677..01fca00b8d 100644
--- a/spec/mspec/lib/mspec/utils/warnings.rb
+++ b/spec/mspec/lib/mspec/utils/warnings.rb
@@ -1,20 +1,6 @@
 require 'mspec/guards/version'
 
 if RUBY_ENGINE == "ruby"
-  ruby_version_is "2.4"..."2.5" do
-    # Kernel#warn does not delegate to Warning.warn in 2.4
-    module Kernel
-      remove_method :warn
-      def warn(*messages)
-        return if $VERBOSE == nil or messages.empty?
-        msg = messages.join("\n")
-        msg += "\n" unless msg.end_with?("\n")
-        Warning.warn(msg)
-      end
-      private :warn
-    end
-  end
-
   def Warning.warn(message)
     # Suppress any warning inside the method to prevent recursion
     verbose = $VERBOSE
diff --git a/spec/ruby/.rubocop.yml b/spec/ruby/.rubocop.yml
index c522f6325a..54780ed435 100644
--- a/spec/ruby/.rubocop.yml
+++ b/spec/ruby/.rubocop.yml
@@ -1,7 +1,7 @@
 inherit_from: .rubocop_todo.yml
 
 AllCops:
-  TargetRubyVersion: 2.4
+  TargetRubyVersion: 2.5
   DisplayCopNames: true
   Exclude:
     - command_line/fixtures/bad_syntax.rb
diff --git a/spec/ruby/CONTRIBUTING.md b/spec/ruby/CONTRIBUTING.md
index d0924867fa..50d8af5931 100644
--- a/spec/ruby/CONTRIBUTING.md
+++ b/spec/ruby/CONTRIBUTING.md
@@ -133,12 +133,12 @@ Here is a list of the most commonly-used guards:
 #### Version guards
 
 ```ruby
-ruby_version_is ""..."2.4" do
-  # Specs for RUBY_VERSION < 2.4
+ruby_version_is ""..."2.6 do
+  # Specs for RUBY_VERSION < 2.6
 end
 
-ruby_version_is "2.4" do
-  # Specs for RUBY_VERSION >= 2.4
+ruby_version_is "2.6 do
+  # Specs for RUBY_VERSION >= 2.6
 end
 ```
 
@@ -185,11 +185,11 @@ end
 #### Combining guards
 
 ```ruby
-guard -> { platform_is :windows and ruby_version_is ""..."2.5" } do
-  # Windows and RUBY_VERSION < 2.5
+guard -> { platform_is :windows and ruby_version_is ""..."2.6" } do
+  # Windows and RUBY_VERSION < 2.6
 end
 
-guard_not -> { platform_is :windows and ruby_version_is ""..."2.5" } do
+guard_not -> { platform_is :windows and ruby_version_is ""..."2.6" } do
   # The opposite
 end
 ```
diff --git a/spec/ruby/README.md b/spec/ruby/README.md
index e6c7153c3d..3c53209762 100644
--- a/spec/ruby/README.md
+++ b/spec/ruby/README.md
@@ -27,8 +27,8 @@ ruby/spec is known to be tested in these implementations for every commit:
 * [TruffleRuby](https://github.com/oracle/truffleruby/tree/master/spec/ruby)
 * [Opal](https://github.com/opal/opal/tree/master/spec)
 
-ruby/spec describes the behavior of Ruby 2.4 and more recent Ruby versions.
-More precisely, every latest stable MRI release should [pass](https://travis-ci.org/ruby/spec) all specs of ruby/spec (2.4.x, 2.5.x, 2.6.x, 2.7.x, etc), and those are tested in TravisCI.
+ruby/spec describes the behavior of Ruby 2.5 and more recent Ruby versions.
+More precisely, every latest stable MRI release should [pass](https://travis-ci.org/ruby/spec) all specs of ruby/spec (2.5.x, 2.6.x, 2.7.x, etc), and those are tested in TravisCI.
 
 The specs are synchronized both ways around once a month by @eregon between ruby/spec, MRI, JRuby and TruffleRuby.
 Each of these repositories has a full copy of the specs under `spec/ruby` to ease editing specs.
@@ -49,6 +49,8 @@ For older specs try these commits:
 * Ruby 2.1.9 - [Suite](https://github.com/ruby/spec/commit/f029e65241374386077ac500add557ae65069b55) using [MSpec](https://github.com/ruby/mspec/commit/55568ea3918c6380e64db8c567d732fa5781efed)
 * Ruby 2.2.10 - [Suite](https://github.com/ruby/spec/commit/cbaa0e412270c944df0c2532fc500c920dba0e92) using [MSpec](https://github.com/ruby/mspec/commit/d84d7668449e96856c5f6bac8cb1526b6d357ce3)
 * Ruby 2.3.8 - [Suite](https://github.com/ruby/spec/commit/dc733114d8ae66a3368ba3a98422c50147a76ba5) using [MSpec](https://github.com/ruby/mspec/commit/4599bc195fb109f2a482a01c32a7d659518369ea)
+* Ruby 2.4.10 - [Suite](https://github.com/ruby/spec/commit/f03892a0a9cac6972e0aa6f83cb08bb8e9b5739c) using [MSpec](https://github.com/ruby/mspec/commit/18fd75a7b4853d79d8148f6a503f99733be91712)
+* Ruby 2.5.8 - [Suite](https://github.com/ruby/spec/commit/f03892a0a9cac6972e0aa6f83cb08bb8e9b5739c) using [MSpec](https://github.com/ruby/mspec/commit/18fd75a7b4853d79d8148f6a503f99733be91712)
 
 ### Running the specs
 
diff --git a/spec/ruby/command_line/dash_l_spec.rb b/spec/ruby/command_line/dash_l_spec.rb
index 51d924edc1..65d6592f22 100644
--- a/spec/ruby/command_line/dash_l_spec.rb
+++ b/spec/ruby/command_line/dash_l_spec.rb
@@ -11,12 +11,10 @@ describe "The -l command line option" do
         "false\nfalse\nfalse\n"
   end
 
-  ruby_version_is "2.5" do
-    it "chomps last line based on $/" do
-      ruby_exe('BEGIN { $/ = "ones\n" }; puts $_', options: "-W0 -n -l", escape: true,
-               args: " < #{@names}").should ==
-          "alice j\nbob field\njames grey\n"
-    end
+  it "chomps last line based on $/" do
+    ruby_exe('BEGIN { $/ = "ones\n" }; puts $_', options: "-W0 -n -l", escape: true,
+             args: " < #{@names}").should ==
+      "alice j\nbob field\njames grey\n"
   end
 
   it "sets $\\ to the value of $/" do
diff --git a/spec/ruby/core/array/append_spec.rb b/spec/ruby/core/array/append_spec.rb
index 61b3efe70d..c12473dc07 100644
--- a/spec/ruby/core/array/append_spec.rb
+++ b/spec/ruby/core/array/append_spec.rb
@@ -35,8 +35,6 @@ describe "Array#<<" do
   end
 end
 
-ruby_version_is "2.5" do
-  describe "Array#append" do
-    it_behaves_like :array_push, :append
-  end
+describe "Array#append" do
+  it_behaves_like :array_push, :append
 end
diff --git a/spec/ruby/core/array/flatten_spec.rb b/spec/ruby/core/array/flatten_spec.rb
index 32be1cba19..e7cd114b9b 100644
--- a/spec/ruby/core/array/flatten_spec.rb
+++ b/spec/ruby/core/array/flatten_spec.rb
@@ -109,20 +109,10 @@ describe "Array#flatten" do
       -> { [@obj].flatten }.should raise_error(TypeError)
     end
 
-    ruby_version_is ""..."2.5" do
-      it "calls respond_to_missing?(:to_ary, false) to try coercing" do
-        def @obj.respond_to_missing?(*args) ScratchPad << args; false end
-        [@obj].flatten.should == [@obj]
-        ScratchPad.recorded.should == [[:to_ary, false]]
-      end
-    end
-
-    ruby_version_is "2.5" do
-      it "calls respond_to_missing?(:to_ary, true) to try coercing" do
-        def @obj.respond_to_missing?(*args) ScratchPad << args; false end
-        [@obj].flatten.should == [@obj]
-        ScratchPad.recorded.should == [[:to_ary, true]]
-      end
+    it "calls respond_to_missing?(:to_ary, true) to try coercing" do
+      def @obj.respond_to_missing?(*args) ScratchPad << args; false end
+      [@obj].flatten.should == [@obj]
+      ScratchPad.recorded.should == [[:to_ary, true]]
     end
 
     it "does not call #to_ary if not defined when #respond_to_missing? returns false" do
diff --git a/spec/ruby/core/array/prepend_spec.rb b/spec/ruby/core/array/prepend_spec.rb
index 22230ec300..368b8dcfcd 100644
--- a/spec/ruby/core/array/prepend_spec.rb
+++ b/spec/ruby/core/array/prepend_spec.rb
@@ -2,8 +2,6 @@ require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 require_relative 'shared/unshift'
 
-ruby_version_is "2.5" do
-  describe "Array#prepend" do
-    it_behaves_like :array_unshift, :prepend
-  end
+describe "Array#prepend" do
+  it_behaves_like :array_unshift, :prepend
 end
diff --git a/spec/ruby/core/binding/irb_spec.rb b/spec/ruby/core/binding/irb_spec.rb
index bd37b419f9..b3bc274f78 100644
--- a/spec/ruby/core/binding/irb_spec.rb
+++ b/spec/ruby/core/binding/irb_spec.rb
@@ -1,18 +1,16 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Binding#irb" do
-    it "creates an IRB session with the binding in scope" do
-      irb_fixture = fixture __FILE__, "irb.rb"
-      irbrc_fixture = fixture __FILE__, "irbrc"
+describe "Binding#irb" do
+  it "creates an IRB session with the binding in scope" do
+    irb_fixture = fixture __FILE__, "irb.rb"
+    irbrc_fixture = fixture __FILE__, "irbrc"
 
-      out = IO.popen([{"IRBRC"=>irbrc_fixture}, *ruby_exe, irb_fixture], "r+") do |pipe|
-        pipe.puts "a ** 2"
-        pipe.puts "exit"
-        pipe.readlines.map(&:chomp)
-      end
-
-      out[-3..-1].should == ["a ** 2", "100", "exit"]
+    out = IO.popen([{"IRBRC"=>irbrc_fixture}, *ruby_exe, irb_fixture], "r+") do |pipe|
+      pipe.puts "a ** 2"
+      pipe.puts "exit"
+      pipe.readlines.map(&:chomp)
     end
+
+    out[-3..-1].should == ["a ** 2", "100", "exit"]
   end
 end
diff --git a/spec/ruby/core/data/constants_spec.rb b/spec/ruby/core/data/constants_spec.rb
index 1b4c0d2df3..0e47a82e26 100644
--- a/spec/ruby/core/data/constants_spec.rb
+++ b/spec/ruby/core/data/constants_spec.rb
@@ -7,9 +7,7 @@ describe "Data" do
     end
   end
 
-  ruby_version_is "2.5" do
-    it "is deprecated" do
-      -> { Data }.should complain(/constant ::Data is deprecated/)
-    end
+  it "is deprecated" do
+    -> { Data }.should complain(/constant ::Data is deprecated/)
   end
 end
diff --git a/spec/ruby/core/dir/children_spec.rb b/spec/ruby/core/dir/children_spec.rb
index 8f6e62b463..e0325a24b8 100644
--- a/spec/ruby/core/dir/children_spec.rb
+++ b/spec/ruby/core/dir/children_spec.rb
@@ -3,71 +3,69 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/common'
 
-ruby_version_is "2.5" do
-  describe "Dir.children" do
-    before :all do
-      DirSpecs.create_mock_dirs
-    end
+describe "Dir.children" do
+  before :all do
+    DirSpecs.create_mock_dirs
+  end
 
-    before :each do
-      @internal = Encoding.default_internal
-    end
+  before :each do
+    @internal = Encoding.default_internal
+  end
 
-    after :all do
-      DirSpecs.delete_mock_dirs
-    end
+  after :all do
+    DirSpecs.delete_mock_dirs
+  end
 
-    after :each do
-      Encoding.default_internal = @internal
-    end
+  after :each do
+    Encoding.default_internal = @internal
+  end
 
-    it "returns an Array of filenames in an existing directory including dotfiles" do
-      a = Dir.children(DirSpecs.mock_dir).sort
+  it "returns an Array of filenames in an existing directory including dotfiles" do
+    a = Dir.children(DirSpecs.mock_dir).sort
 
-      a.should == DirSpecs.expected_paths - %w[. ..]
+    a.should == DirSpecs.expected_paths - %w[. ..]
 
-      a = Dir.children("#{DirSpecs.mock_dir}/deeply/nested").sort
-      a.should == %w|.dotfile.ext directory|
-    end
+    a = Dir.children("#{DirSpecs.mock_dir}/deeply/nested").sort
+    a.should == %w|.dotfile.ext directory|
+  end
 
-    it "calls #to_path on non-String arguments" do
-      p = mock('path')
-      p.should_receive(:to_path).and_return(DirSpecs.mock_dir)
-      Dir.children(p)
-    end
+  it "calls #to_path on non-String arguments" do
+    p = mock('path')
+    p.should_receive(:to_path).and_return(DirSpecs.mock_dir)
+    Dir.children(p)
+  end
 
-    it "accepts an options Hash" do
-      a = Dir.children("#{DirSpecs.mock_dir}/deeply/nested", encoding: "utf-8").sort
-      a.should == %w|.dotfile.ext directory|
-    end
+  it "accepts an options Hash" do
+    a = Dir.children("#{DirSpecs.mock_dir}/deeply/nested", encoding: "utf-8").sort
+    a.should == %w|.dotfile.ext directory|
+  end
 
-    it "returns children encoded with the filesystem encoding by default" do
-      # This spec depends on the locale not being US-ASCII because if it is, the
-      # children that are not ascii_only? will be BINARY encoded.
-      children = Dir.children(File.join(DirSpecs.mock_dir, 'special')).sort
-      encoding = Encoding.find("filesystem")
-      encoding = Encoding::BINARY if encoding == Encoding::US_ASCII
-      platform_is_not :windows do
-        children.should include("こんにちは.txt".force_encoding(encoding))
-      end
-      children.first.encoding.should equal(Encoding.find("filesystem"))
+  it "returns children encoded with the filesystem encoding by default" do
+    # This spec depends on the locale not being US-ASCII because if it is, the
+    # children that are not ascii_only? will be BINARY encoded.
+    children = Dir.children(File.join(DirSpecs.mock_dir, 'special')).sort
+    encoding = Encoding.find("filesystem")
+    encoding = Encoding::BINARY if encoding == Encoding::US_ASCII
+    platform_is_not :windows do
+      children.should include("こんにちは.txt".force_encoding(encoding))
     end
+    children.first.encoding.should equal(Encoding.find("filesystem"))
+  end
 
-    it "returns children encoded with the specified encoding" do
-      dir = File.join(DirSpecs.mock_dir, 'special')
-      children = Dir.children(dir, encoding: "euc-jp").sort
-      children.first.encoding.should equal(Encoding::EUC_JP)
-    end
+  it "returns children encoded with the specified encoding" do
+    dir = File.join(DirSpecs.mock_dir, 'special')
+    children = Dir.children(dir, encoding: "euc-jp").sort
+    children.first.encoding.should equal(Encoding::EUC_JP)
+  end
 
-    it "returns children transcoded to the default internal encoding" do
-      Encoding.default_internal = Encoding::EUC_KR
-      children = Dir.children(File.join(DirSpecs.mock_dir, 'special')).sort
-      children.first.encoding.should equal(Encoding::EUC_KR)
-    end
+  it "returns children transcoded to the default internal encoding" do
+    Encoding.default_internal = Encoding::EUC_KR
+    children = Dir.children(File.join(DirSpecs.mock_dir, 'special')).sort
+    children.first.encoding.should equal(Encoding::EUC_KR)
+  end
 
-    it "raises a SystemCallError if called with a nonexistent directory" do
-      -> { Dir.children DirSpecs.nonexistent }.should raise_error(SystemCallError)
-    end
+  it "raises a SystemCallError if called with a nonexistent directory" do
+    -> { Dir.children DirSpecs.nonexistent }.should raise_error(SystemCallError)
   end
 end
 
diff --git a/spec/ruby/core/dir/each_child_spec.rb b/spec/ruby/core/dir/each_child_spec.rb
index dcc9a456c7..93b4a1aec1 100644
--- a/spec/ruby/core/dir/each_child_spec.rb
+++ b/spec/ruby/core/dir/each_child_spec.rb
@@ -1,51 +1,49 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/common'
 
-ruby_version_is "2.5" do
-  describe "Dir.each_child" do
-    before :all do
-      DirSpecs.create_mock_dirs
-    end
+describe "Dir.each_child" do
+  before :all do
+    DirSpecs.create_mock_dirs
+  end
 
-    after :all do
-      DirSpecs.delete_mock_dirs
-    end
+  after :all do
+    DirSpecs.delete_mock_dirs
+  end
 
-    it "yields all names in an existing directory to the provided block" do
-      a, b = [], []
+  it "yields all names in an existing directory to the provided block" do
+    a, b = [], []
 
-      Dir.each_child(DirSpecs.mock_dir) {|f| a << f}
-      Dir.each_child("#{DirSpecs.mock_dir}/deeply/nested") {|f| b << f}
+    Dir.each_child(DirSpecs.mock_dir) {|f| a << f}
+    Dir.each_child("#{DirSpecs.mock_dir}/deeply/nested") {|f| b << f}
 
-      a.sort.should == DirSpecs.expected_paths -  %w[. ..]
-      b.sort.should == %w|.dotfile.ext directory|
-    end
+    a.sort.should == DirSpecs.expected_paths -  %w[. ..]
+    b.sort.should == %w|.dotfile.ext directory|
+  end
 
-    it "returns nil when successful" do
-      Dir.each_child(DirSpecs.mock_dir) {|f| f}.should == nil
-    end
+  it "returns nil when successful" do
+    Dir.each_child(DirSpecs.mock_dir) {|f| f}.should == nil
+  end
 
-    it "calls #to_path on non-String arguments" do
-      p = mock('path')
-      p.should_receive(:to_path).and_return(DirSpecs.mock_dir)
-      Dir.each_child(p).to_a
-    end
+  it "calls #to_path on non-String arguments" do
+    p = mock('path')
+    p.should_receive(:to_path).and_return(DirSpecs.mock_dir)
+    Dir.each_child(p).to_a
+  end
 
-    it "raises a SystemCallError if passed a nonexistent directory" do
-      -> { Dir.each_child(DirSpecs.nonexistent) {} }.should raise_error(SystemCallError)
-    end
+  it "raises a SystemCallError if passed a nonexistent directory" do
+    -> { Dir.each_child(DirSpecs.nonexistent) {} }.should raise_error(SystemCallError)
+  end
 
-    describe "when no block is given" do
-      it "returns an Enumerator" do
-        Dir.each_child(DirSpecs.mock_dir).should be_an_instance_of(Enumerator)
-        Dir.each_child(DirSpecs.mock_dir).to_a.sort.should == DirSpecs.expected_paths - %w[. ..]
-      end
+  describe "when no block is given" do
+    it "returns an Enumerator" do
+      Dir.each_child(DirSpecs.mock_dir).should be_an_instance_of(Enumerator)
+      Dir.each_child(DirSpecs.mock_dir).to_a.sort.should == DirSpecs.expected_paths - %w[. ..]
+    end
 
-      describe "returned Enumerator" do
-        describe "size" do
-          it "should return nil" do
-            Dir.each_child(DirSpecs.mock_dir).size.should == nil
-          end
+    describe "returned Enumerator" do
+      describe "size" do
+        it "should return nil" do
+          Dir.each_child(DirSpecs.mock_dir).size.should == nil
         end
       end
     end
diff --git a/spec/ruby/core/dir/shared/glob.rb b/spec/ruby/core/dir/shared/glob.rb
index b47e23b41c..0fcfcc4eea 100644
--- a/spec/ruby/core/dir/shared/glob.rb
+++ b/spec/ruby/core/dir/shared/glob.rb
@@ -291,74 +291,72 @@ describe :dir_glob, shared: true do
     end
   end
 
-  ruby_version_is "2.5" do
-    context ":base option passed" do
-      before :each do
-        @mock_dir = File.expand_path tmp('dir_glob_mock')
+  context ":base option passed" do
+    before :each do
+      @mock_dir = File.expand_path tmp('dir_glob_mock')
 
-        %w[
+      %w[
           a/b/x
           a/b/c/y
           a/b/c/d/z
         ].each do |path|
-          file = File.join @mock_dir, path
-          mkdir_p File.dirname(file)
-          touch file
-        end
+        file = File.join @mock_dir, path
+        mkdir_p File.dirname(file)
+        touch file
       end
+    end
 
-      after :each do
-        rm_r @mock_dir
-      end
+    after :each do
+      rm_r @mock_dir
+    end
 
-      it "matches entries only from within the specified directory" do
-        path = File.join(@mock_dir, "a/b/c")
-        Dir.send(@method, "*", base: path).sort.should == %w( d y )
-      end
+    it "matches entries only from within the specified directory" do
+      path = File.join(@mock_dir, "a/b/c")
+      Dir.send(@method, "*", base: path).sort.should == %w( d y )
+    end
 
-      it "accepts both relative and absolute paths" do
-        require 'pathname'
+    it "accepts both relative and absolute paths" do
+      require 'pathname'
 
-        path_abs = File.join(@mock_dir, "a/b/c")
-        path_rel = Pathname.new(path_abs).relative_path_from(Pathname.new(Dir.pwd))
+      path_abs = File.join(@mock_dir, "a/b/c")
+      path_rel = Pathname.new(path_abs).relative_path_from(Pathname.new(Dir.pwd))
 
-        result_abs = Dir.send(@method, "*", base: path_abs).sort
-        result_rel = Dir.send(@method, "*", base: path_rel).sort
+      result_abs = Dir.send(@method, "*", base: path_abs).sort
+      result_rel = Dir.send(@method, "*", base: path_rel).sort
 
-        result_abs.should == %w( d y )
-        result_rel.should == %w( d y )
-      end
+      result_abs.should == %w( d y )
+      result_rel.should == %w( d y )
+    end
 
-      it "returns [] if specified path does not exist" do
-        path = File.join(@mock_dir, "fake-name")
-        File.should_not.exist?(path)
+    it "returns [] if specified path does not exist" do
+      path = File.join(@mock_dir, "fake-name")
+      File.should_not.exist?(path)
 
-        Dir.send(@method, "*", base: path).should == []
-      end
+      Dir.send(@method, "*", base: path).should == []
+    end
 
-      it "returns [] if specified path is a file" do
-        path = File.join(@mock_dir, "a/b/x")
-        File.should.exist?(path)
+    it "returns [] if specified path is a file" do
+      path = File.join(@mock_dir, "a/b/x")
+      File.should.exist?(path)
 
-        Dir.send(@method, "*", base: path).should == []
-      end
+      Dir.send(@method, "*", base: path).should == []
+    end
 
-      it "raises TypeError when cannot convert value to string" do
-        -> {
-          Dir.send(@method, "*", base: [])
-        }.should raise_error(TypeError)
-      end
+    it "raises TypeError when cannot convert value to string" do
+      -> {
+        Dir.send(@method, "*", base: [])
+      }.should raise_error(TypeError)
+    end
 
-      it "handles '' as current directory path" do
-        Dir.chdir @mock_dir do
-          Dir.send(@method, "*", base: "").should == %w( a )
-        end
+    it "handles '' as current directory path" do
+      Dir.chdir @mock_dir do
+        Dir.send(@method, "*", base: "").should == %w( a )
       end
+    end
 
-      it "handles nil as current directory path" do
-        Dir.chdir @mock_dir do
-          Dir.send(@method, "*", base: nil).should == %w( a )
-        end
+    it "handles nil as current directory path" do
+      Dir.chdir @mock_dir do
+        Dir.send(@method, "*", base: nil).should == %w( a )
       end
     end
   end
diff --git a/spec/ruby/core/enumerable/all_spec.rb b/spec/ruby/core/enumerable/all_spec.rb
index 8af80896a9..ae255c662c 100644
--- a/spec/ruby/core/enumerable/all_spec.rb
+++ b/spec/ruby/core/enumerable/all_spec.rb
@@ -26,15 +26,6 @@ describe "Enumerable#all?" do
     -> { {}.all?(1, 2, 3) }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises an ArgumentError when any arguments provided" do
-      -> { @enum.all?(Proc.new {}) }.should raise_error(ArgumentError)
-      -> { @enum.all?(nil) }.should raise_error(ArgumentError)
-      -> { @empty.all?(1) }.should raise_error(ArgumentError)
-      -> { @enum1.all?(1) {} }.should raise_error(ArgumentError)
-    end
-  end
-
   it "does not hide exceptions out of #each" do
     -> {
       EnumerableSpecs::ThrowingEach.new.all?
@@ -133,69 +124,67 @@ describe "Enumerable#all?" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe 'when given a pattern argument' do
-      it "calls `===` on the pattern the return value " do
-        pattern = EnumerableSpecs::Pattern.new { |x| x >= 0 }
-        @enum1.all?(pattern).should == false
-        pattern.yielded.should == [[0], [1], [2], [-1]]
-      end
+  describe 'when given a pattern argument' do
+    it "calls `===` on the pattern the return value " do
+      pattern = EnumerableSpecs::Pattern.new { |x| x >= 0 }
+      @enum1.all?(pattern).should == false
+      pattern.yielded.should == [[0], [1], [2], [-1]]
+    end
 
-      # may raise an exception in future versions
-      ruby_version_is ""..."2.6" do
-        it "ignores block" do
-          @enum2.all?(NilClass) { raise }.should == false
-          [1, 2, nil].all?(NilClass) { raise }.should == false
-          {a: 1}.all?(Array) { raise }.should == true
-        end
+    # may raise an exception in future versions
+    ruby_version_is ""..."2.6" do
+      it "ignores block" do
+        @enum2.all?(NilClass) { raise }.should == false
+        [1, 2, nil].all?(NilClass) { raise }.should == false
+        {a: 1}.all?(Array) { raise }.should == true
       end
+    end
 
-      it "always returns true on empty enumeration" do
-        @empty.all?(Integer).should == true
-        [].all?(Integer).should == true
-        {}.all?(NilClass).should == true
-      end
+    it "always returns true on empty enumeration" do
+      @empty.all?(Integer).should == true
+      [].all?(Integer).should == true
+      {}.all?(NilClass).should == true
+    end
 
-      it "does not hide exceptions out of #each" do
-        -> {
-          EnumerableSpecs::ThrowingEach.new.all?(Integer)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of #each" do
+      -> {
+        EnumerableSpecs::ThrowingEach.new.all?(Integer)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "returns true if the pattern never returns false or nil" do
-        pattern = EnumerableSpecs::Pattern.new { |x| 42 }
-        @enum.all?(pattern).should == true
+    it "returns true if the pattern never returns false or nil" do
+      pattern = EnumerableSpecs::Pattern.new { |x| 42 }
+      @enum.all?(pattern).should == true
 
-        [1, 42, 3].all?(pattern).should == true
+      [1, 42, 3].all?(pattern).should == true
 
-        pattern = EnumerableSpecs::Pattern.new { |x| Array === x }
-        {a: 1, b: 2}.all?(pattern).should == true
-      end
+      pattern = EnumerableSpecs::Pattern.new { |x| Array === x }
+      {a: 1, b: 2}.all?(pattern).should == true
+    end
 
-      it "returns false if the pattern ever returns false or nil" do
-        pattern = EnumerableSpecs::Pattern.new { |x| x >= 0 }
-        @enum1.all?(pattern).should == false
-        pattern.yielded.should == [[0], [1], [2], [-1]]
+    it "returns false if the pattern ever returns false or nil" do
+      pattern = EnumerableSpecs::Pattern.new { |x| x >= 0 }
+      @enum1.all?(pattern).should == false
+      pattern.yielded.should == [[0], [1], [2], [-1]]
 
-        [1, 2, 3, -1].all?(pattern).should == false
+      [1, 2, 3, -1].all?(pattern).should == false
 
-        pattern = EnumerableSpecs::Pattern.new { |x| x[1] >= 0 }
-        {a: 1, b: -1}.all?(pattern).should == false
-      end
+      pattern = EnumerableSpecs::Pattern.new { |x| x[1] >= 0 }
+      {a: 1, b: -1}.all?(pattern).should == false
+    end
 
-      it "does not hide exceptions out of pattern#===" do
-        pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
-        -> {
-          @enum.all?(pattern)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of pattern#===" do
+      pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
+      -> {
+        @enum.all?(pattern)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "calls the pattern with gathered array when yielded with multiple arguments" do
-        multi = EnumerableSpecs::YieldsMulti.new
-        pattern = EnumerableSpecs::Pattern.new { true }
-        multi.all?(pattern).should == true
-        pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
-      end
+    it "calls the pattern with gathered array when yielded with multiple arguments" do
+      multi = EnumerableSpecs::YieldsMulti.new
+      pattern = EnumerableSpecs::Pattern.new { true }
+      multi.all?(pattern).should == true
+      pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
     end
   end
 end
diff --git a/spec/ruby/core/enumerable/any_spec.rb b/spec/ruby/core/enumerable/any_spec.rb
index c800fe2d4b..0202506d10 100644
--- a/spec/ruby/core/enumerable/any_spec.rb
+++ b/spec/ruby/core/enumerable/any_spec.rb
@@ -26,15 +26,6 @@ describe "Enumerable#any?" do
     -> { {}.any?(1, 2, 3) }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises an ArgumentError when any arguments provided" do
-      -> { @enum.any?(Proc.new {}) }.should raise_error(ArgumentError)
-      -> { @enum.any?(nil) }.should raise_error(ArgumentError)
-      -> { @empty.any?(1) }.should raise_error(ArgumentError)
-      -> { @enum1.any?(1) {} }.should raise_error(ArgumentError)
-    end
-  end
-
   it "does not hide exceptions out of #each" do
     -> {
       EnumerableSpecs::ThrowingEach.new.any?
@@ -147,68 +138,66 @@ describe "Enumerable#any?" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe 'when given a pattern argument' do
-      it "calls `===` on the pattern the return value " do
-        pattern = EnumerableSpecs::Pattern.new { |x| x == 2 }
-        @enum1.any?(pattern).should == true
-        pattern.yielded.should == [[0], [1], [2]]
-      end
+  describe 'when given a pattern argument' do
+    it "calls `===` on the pattern the return value " do
+      pattern = EnumerableSpecs::Pattern.new { |x| x == 2 }
+      @enum1.any?(pattern).should == true
+      pattern.yielded.should == [[0], [1], [2]]
+    end
 
-      # may raise an exception in future versions
-      ruby_version_is ""..."2.6" do
-        it "ignores block" do
-          @enum2.any?(NilClass) { raise }.should == true
-          [1, 2, nil].any?(NilClass) { raise }.should == true
-          {a: 1}.any?(Array) { raise }.should == true
-        end
+    # may raise an exception in future versions
+    ruby_version_is ""..."2.6" do
+      it "ignores block" do
+        @enum2.any?(NilClass) { raise }.should == true
+        [1, 2, nil].any?(NilClass) { raise }.should == true
+        {a: 1}.any?(Array) { raise }.should == true
       end
+    end
 
-      it "always returns false on empty enumeration" do
-        @empty.any?(Integer).should == false
-        [].any?(Integer).should == false
-        {}.any?(NilClass).should == false
-      end
+    it "always returns false on empty enumeration" do
+      @empty.any?(Integer).should == false
+      [].any?(Integer).should == false
+      {}.any?(NilClass).should == false
+    end
 
-      it "does not hide exceptions out of #each" do
-        -> {
-          EnumerableSpecs::ThrowingEach.new.any?(Integer)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of #each" do
+      -> {
+        EnumerableSpecs::ThrowingEach.new.any?(Integer)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "returns true if the pattern ever returns a truthy value" do
-        @enum2.any?(NilClass).should == true
-        pattern = EnumerableSpecs::Pattern.new { |x| 42 }
-        @enum.any?(pattern).should == true
+    it "returns true if the pattern ever returns a truthy value" do
+      @enum2.any?(NilClass).should == true
+      pattern = EnumerableSpecs::Pattern.new { |x| 42 }
+      @enum.any?(pattern).should == true
 
-        [1, 42, 3].any?(pattern).should == true
+      [1, 42, 3].any?(pattern).should == true
 
-        pattern = EnumerableSpecs::Pattern.new { |x| x == [:b, 2] }
-        {a: 1, b: 2}.any?(pattern).should == true
-      end
+      pattern = EnumerableSpecs::Pattern.new { |x| x == [:b, 2] }
+      {a: 1, b: 2}.any?(pattern).should == true
+    end
 
-      it "returns false if the block never returns other than false or nil" do
-        pattern = EnumerableSpecs::Pattern.new { |x| nil }
-        @enum1.any?(pattern).should == false
-        pattern.yielded.should == [[0], [1], [2], [-1]]
+    it "returns false if the block never returns other than false or nil" do
+      pattern = EnumerableSpecs::Pattern.new { |x| nil }
+      @enum1.any?(pattern).should == false
+      pattern.yielded.should == [[0], [1], [2], [-1]]
 
-        [1, 2, 3].any?(pattern).should == false
-        {a: 1}.any?(pattern).should == false
-      end
+      [1, 2, 3].any?(pattern).should == false
+      {a: 1}.any?(pattern).should == false
+    end
 
-      it "does not hide exceptions out of pattern#===" do
-        pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
-        -> {
-          @enum.any?(pattern)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of pattern#===" do
+      pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
+      -> {
+        @enum.any?(pattern)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "calls the pattern with gathered array when yielded with multiple arguments" do
-        multi = EnumerableSpecs::YieldsMulti.new
-        pattern = EnumerableSpecs::Pattern.new { false }
-        multi.any?(pattern).should == false
-        pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
-      end
+    it "calls the pattern with gathered array when yielded with multiple arguments" do
+      multi = EnumerableSpecs::YieldsMulti.new
+      pattern = EnumerableSpecs::Pattern.new { false }
+      multi.any?(pattern).should == false
+      pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
     end
   end
 end
diff --git a/spec/ruby/core/enumerable/none_spec.rb b/spec/ruby/core/enumerable/none_spec.rb
index 7c17e58a13..8c886736ab 100644
--- a/spec/ruby/core/enumerable/none_spec.rb
+++ b/spec/ruby/core/enumerable/none_spec.rb
@@ -20,15 +20,6 @@ describe "Enumerable#none?" do
     -> { {}.none?(1, 2, 3) }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises an ArgumentError when any arguments provided" do
-      -> { @enum.none?(Proc.new {}) }.should raise_error(ArgumentError)
-      -> { @enum.none?(nil) }.should raise_error(ArgumentError)
-      -> { @empty.none?(1) }.should raise_error(ArgumentError)
-      -> { @enum.none?(1) {} }.should raise_error(ArgumentError)
-    end
-  end
-
   it "does not hide exceptions out of #each" do
     -> {
       EnumerableSpecs::ThrowingEach.new.none?
@@ -102,66 +93,64 @@ describe "Enumerable#none?" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe 'when given a pattern argument' do
-      it "calls `===` on the pattern the return value " do
-        pattern = EnumerableSpecs::Pattern.new { |x| x == 3 }
-        @enum1.none?(pattern).should == true
-        pattern.yielded.should == [[0], [1], [2], [-1]]
-      end
+  describe 'when given a pattern argument' do
+    it "calls `===` on the pattern the return value " do
+      pattern = EnumerableSpecs::Pattern.new { |x| x == 3 }
+      @enum1.none?(pattern).should == true
+      pattern.yielded.should == [[0], [1], [2], [-1]]
+    end
 
-      # may raise an exception in future versions
-      ruby_version_is ""..."2.6" do
-        it "ignores block" do
-          @enum2.none?(Integer) { raise }.should == true
-          [1, 2, nil].none?(TrueClass) { raise }.should == true
-          {a: 1}.none?(Hash) { raise }.should == true
-        end
+    # may raise an exception in future versions
+    ruby_version_is ""..."2.6" do
+      it "ignores block" do
+        @enum2.none?(Integer) { raise }.should == true
+        [1, 2, nil].none?(TrueClass) { raise }.should == true
+        {a: 1}.none?(Hash) { raise }.should == true
       end
+    end
 
-      it "always returns true on empty enumeration" do
-        @empty.none?(Integer).should == true
-        [].none?(Integer).should == true
-        {}.none?(NilClass).should == true
-      end
+    it "always returns true on empty enumeration" do
+      @empty.none?(Integer).should == true
+      [].none?(Integer).should == true
+      {}.none?(NilClass).should == true
+    end
 
-      it "does not hide exceptions out of #each" do
-        -> {
-          EnumerableSpecs::ThrowingEach.new.none?(Integer)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of #each" do
+      -> {
+        EnumerableSpecs::ThrowingEach.new.none?(Integer)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "returns true if the pattern never returns a truthy value" do
-        @enum2.none?(Integer).should == true
-        pattern = EnumerableSpecs::Pattern.new { |x| nil }
-        @enum.none?(pattern).should == true
+    it "returns true if the pattern never returns a truthy value" do
+      @enum2.none?(Integer).should == true
+      pattern = EnumerableSpecs::Pattern.new { |x| nil }
+      @enum.none?(pattern).should == true
 
-        [1, 42, 3].none?(pattern).should == true
-        {a: 1, b: 2}.none?(pattern).should == true
-      end
+      [1, 42, 3].none?(pattern).should == true
+      {a: 1, b: 2}.none?(pattern).should == true
+    end
 
-      it "returns false if the pattern ever returns other than false or nil" do
-        pattern = EnumerableSpecs::Pattern.new { |x| x < 0 }
-        @enum1.none?(pattern).should == false
-        pattern.yielded.should == [[0], [1], [2], [-1]]
+    it "returns false if the pattern ever returns other than false or nil" do
+      pattern = EnumerableSpecs::Pattern.new { |x| x < 0 }
+      @enum1.none?(pattern).should == false
+      pattern.yielded.should == [[0], [1], [2], [-1]]
 
-        [1, 2, 3, -1].none?(pattern).should == false
-        {a: 1}.none?(Array).should == false
-      end
+      [1, 2, 3, -1].none?(pattern).should == false
+      {a: 1}.none?(Array).should == false
+    end
 
-      it "does not hide exceptions out of pattern#===" do
-        pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
-        -> {
-          @enum.none?(pattern)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of pattern#===" do
+      pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
+      -> {
+        @enum.none?(pattern)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "calls the pattern with gathered array when yielded with multiple arguments" do
-        multi = EnumerableSpecs::YieldsMulti.new
-        pattern = EnumerableSpecs::Pattern.new { false }
-        multi.none?(pattern).should == true
-        pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
-      end
+    it "calls the pattern with gathered array when yielded with multiple arguments" do
+      multi = EnumerableSpecs::YieldsMulti.new
+      pattern = EnumerableSpecs::Pattern.new { false }
+      multi.none?(pattern).should == true
+      pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
     end
   end
 end
diff --git a/spec/ruby/core/enumerable/one_spec.rb b/spec/ruby/core/enumerable/one_spec.rb
index 2ae8b3efa4..46a10d68eb 100644
--- a/spec/ruby/core/enumerable/one_spec.rb
+++ b/spec/ruby/core/enumerable/one_spec.rb
@@ -20,15 +20,6 @@ describe "Enumerable#one?" do
     -> { {}.one?(1, 2, 3) }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises an ArgumentError when any arguments provided" do
-      -> { @enum.one?(Proc.new {}) }.should raise_error(ArgumentError)
-      -> { @enum.one?(nil) }.should raise_error(ArgumentError)
-      -> { @empty.one?(1) }.should raise_error(ArgumentError)
-      -> { @enum.one?(1) {} }.should raise_error(ArgumentError)
-    end
-  end
-
   it "does not hide exceptions out of #each" do
     -> {
       EnumerableSpecs::ThrowingEach.new.one?
@@ -93,77 +84,75 @@ describe "Enumerable#one?" do
   end
 
 
-  ruby_version_is "2.5" do
-    describe 'when given a pattern argument' do
-      it "calls `===` on the pattern the return value " do
-        pattern = EnumerableSpecs::Pattern.new { |x| x == 1 }
-        @enum1.one?(pattern).should == true
-        pattern.yielded.should == [[0], [1], [2], [-1]]
-      end
+  describe 'when given a pattern argument' do
+    it "calls `===` on the pattern the return value " do
+      pattern = EnumerableSpecs::Pattern.new { |x| x == 1 }
+      @enum1.one?(pattern).should == true
+      pattern.yielded.should == [[0], [1], [2], [-1]]
+    end
 
-      # may raise an exception in future versions
-      ruby_version_is ""..."2.6" do
-        it "ignores block" do
-          @enum2.one?(NilClass) { raise }.should == true
-          [1, 2, nil].one?(NilClass) { raise }.should == true
-          {a: 1}.one?(Array) { raise }.should == true
-        end
+    # may raise an exception in future versions
+    ruby_version_is ""..."2.6" do
+      it "ignores block" do
+        @enum2.one?(NilClass) { raise }.should == true
+        [1, 2, nil].one?(NilClass) { raise }.should == true
+        {a: 1}.one?(Array) { raise }.should == true
       end
+    end
 
-      it "always returns false on empty enumeration" do
-        @empty.one?(Integer).should == false
-        [].one?(Integer).should == false
-        {}.one?(NilClass).should == false
-      end
+    it "always returns false on empty enumeration" do
+      @empty.one?(Integer).should == false
+      [].one?(Integer).should == false
+      {}.one?(NilClass).should == false
+    end
 
-      it "does not hide exceptions out of #each" do
-        -> {
-          EnumerableSpecs::ThrowingEach.new.one?(Integer)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of #each" do
+      -> {
+        EnumerableSpecs::ThrowingEach.new.one?(Integer)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "returns true if the pattern returns a truthy value only once" do
-        @enum2.one?(NilClass).should == true
-        pattern = EnumerableSpecs::Pattern.new { |x| x == 2 }
-        @enum1.one?(pattern).should == true
+    it "returns true if the pattern returns a truthy value only once" do
+      @enum2.one?(NilClass).should == true
+      pattern = EnumerableSpecs::Pattern.new { |x| x == 2 }
+      @enum1.one?(pattern).should == true
 
-        [1, 2, 42, 3].one?(pattern).should == true
+      [1, 2, 42, 3].one?(pattern).should == true
 
-        pattern = EnumerableSpecs::Pattern.new { |x| x == [:b, 2] }
-        {a: 1, b: 2}.one?(pattern).should == true
-      end
+      pattern = EnumerableSpecs::Pattern.new { |x| x == [:b, 2] }
+      {a: 1, b: 2}.one?(pattern).should == true
+    end
 
-      it "returns false if the pattern returns a truthy value more than once" do
-        pattern = EnumerableSpecs::Pattern.new { |x| !x }
-        @enum2.one?(pattern).should == false
-        pattern.yielded.should == [[nil], [false]]
+    it "returns false if the pattern returns a truthy value more than once" do
+      pattern = EnumerableSpecs::Pattern.new { |x| !x }
+      @enum2.one?(pattern).should == false
+      pattern.yielded.should == [[nil], [false]]
 
-        [1, 2, 3].one?(Integer).should == false
-        {a: 1, b: 2}.one?(Array).should == false
-      end
+      [1, 2, 3].one?(Integer).should == false
+      {a: 1, b: 2}.one?(Array).should == false
+    end
 
-      it "returns false if the pattern never returns a truthy value" do
-        pattern = EnumerableSpecs::Pattern.new { |x| nil }
-        @enum1.one?(pattern).should == false
-        pattern.yielded.should == [[0], [1], [2], [-1]]
+    it "returns false if the pattern never returns a truthy value" do
+      pattern = EnumerableSpecs::Pattern.new { |x| nil }
+      @enum1.one?(pattern).should == false
+      pattern.yielded.should == [[0], [1], [2], [-1]]
 
-        [1, 2, 3].one?(pattern).should == false
-        {a: 1}.one?(pattern).should == false
-      end
+      [1, 2, 3].one?(pattern).should == false
+      {a: 1}.one?(pattern).should == false
+    end
 
-      it "does not hide exceptions out of pattern#===" do
-        pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
-        -> {
-          @enum.one?(pattern)
-        }.should raise_error(RuntimeError)
-      end
+    it "does not hide exceptions out of pattern#===" do
+      pattern = EnumerableSpecs::Pattern.new { raise "from pattern" }
+      -> {
+        @enum.one?(pattern)
+      }.should raise_error(RuntimeError)
+    end
 
-      it "calls the pattern with gathered array when yielded with multiple arguments" do
-        multi = EnumerableSpecs::YieldsMulti.new
-        pattern = EnumerableSpecs::Pattern.new { false }
-        multi.one?(pattern).should == false
-        pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
-      end
+    it "calls the pattern with gathered array when yielded with multiple arguments" do
+      multi = EnumerableSpecs::YieldsMulti.new
+      pattern = EnumerableSpecs::Pattern.new { false }
+      multi.one?(pattern).should == false
+      pattern.yielded.should == [[[1, 2]], [[3, 4, 5]], [[6, 7, 8, 9]]]
     end
   end
 end
diff --git a/spec/ruby/core/exception/full_message_spec.rb b/spec/ruby/core/exception/full_message_spec.rb
index 3df2d47f61..9cac9fb037 100644
--- a/spec/ruby/core/exception/full_message_spec.rb
+++ b/spec/ruby/core/exception/full_message_spec.rb
@@ -1,94 +1,92 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Exception#full_message" do
-    it "returns formatted string of exception using the same format that is used to print an uncaught exceptions to stderr" do
-      e = RuntimeError.new("Some runtime error")
-      e.set_backtrace(["a.rb:1", "b.rb:2"])
+describe "Exception#full_message" do
+  it "returns formatted string of exception using the same format that is used to print an uncaught exceptions to stderr" do
+    e = RuntimeError.new("Some runtime error")
+    e.set_backtrace(["a.rb:1", "b.rb:2"])
 
-      full_message = e.full_message
-      full_message.should include "RuntimeError"
-      full_message.should include "Some runtime error"
-      full_message.should include "a.rb:1"
-      full_message.should include "b.rb:2"
-    end
+    full_message = e.full_message
+    full_message.should include "RuntimeError"
+    full_message.should include "Some runtime error"
+    full_message.should include "a.rb:1"
+    full_message.should include "b.rb:2"
+  end
 
-    ruby_version_is "2.5.1" do
-      it "supports :highlight option and adds escape sequences to highlight some strings" do
-        e = RuntimeError.new("Some runtime error")
+  ruby_version_is "2.5.1" do
+    it "supports :highlight option and adds escape sequences to highlight some strings" do
+      e = RuntimeError.new("Some runtime error")
 
-        full_message = e.full_message(highlight: true, order: :bottom)
-        full_message.should include "\e[1mTraceback\e[m (most recent call last)"
-        full_message.should include "\e[1mSome runtime error (\e[1;4mRuntimeError\e[m\e[1m)"
+      full_message = e.full_message(highlight: true, order: :bottom)
+      full_message.should include "\e[1mTraceback\e[m (most recent call last)"
+      full_message.should include "\e[1mSome runtime error (\e[1;4mRuntimeError\e[m\e[1m)"
 
-        full_message = e.full_message(highlight: false, order: :bottom)
-        full_message.should include "Traceback (most recent call last)"
-        full_message.should include "Some runtime error (RuntimeError)"
-      end
+      full_message = e.full_message(highlight: false, order: :bottom)
+      full_message.should include "Traceback (most recent call last)"
+      full_message.should include "Some runtime error (RuntimeError)"
+    end
 
-      it "supports :order option and places the error message and the backtrace at the top or the bottom" do
-        e = RuntimeError.new("Some runtime error")
-        e.set_backtrace(["a.rb:1", "b.rb:2"])
+    it "supports :order option and places the error message and the backtrace at the top or the bottom" do
+      e = RuntimeError.new("Some runtime error")
+      e.set_backtrace(["a.rb:1", "b.rb:2"])
 
-        e.full_message(order: :top,    highlight: false).should =~ /a.rb:1.*b.rb:2/m
-        e.full_message(order: :bottom, highlight: false).should =~ /b.rb:2.*a.rb:1/m
-      end
+      e.full_message(order: :top,    highlight: false).should =~ /a.rb:1.*b.rb:2/m
+      e.full_message(order: :bottom, highlight: false).should =~ /b.rb:2.*a.rb:1/m
+    end
 
-      it "shows the caller if the exception has no backtrace" do
-        e = RuntimeError.new("Some runtime error")
-        e.backtrace.should == nil
-        full_message = e.full_message(highlight: false, order: :top)
-        full_message.should include("#{__FILE__}:#{__LINE__-1}:in `")
-        full_message.should include("': Some runtime error (RuntimeError)\n")
-      end
+    it "shows the caller if the exception has no backtrace" do
+      e = RuntimeError.new("Some runtime error")
+      e.backtrace.should == nil
+      full_message = e.full_message(highlight: false, order: :top)
+      full_message.should include("#{__FILE__}:#{__LINE__-1}:in `")
+      full_message.should include("': Some runtime error (RuntimeError)\n")
+    end
 
-      it "shows the exception class at the end of the first line of the message when the message contains multiple lines" do
-        begin
-          line = __LINE__; raise "first line\nsecond line"
-        rescue => e
-          full_message = e.full_message(highlight: false, order: :top).lines
-          full_message[0].should include("#{__FILE__}:#{line}:in `")
-          full_message[0].should include(": first line (RuntimeError)\n")
-          full_message[1].should == "second line\n"
-        end
+    it "shows the exception class at the end of the first line of the message when the message contains multiple lines" do
+      begin
+        line = __LINE__; raise "first line\nsecond line"
+      rescue => e
+        full_message = e.full_message(highlight: false, order: :top).lines
+        full_message[0].should include("#{__FILE__}:#{line}:in `")
+        full_message[0].should include(": first line (RuntimeError)\n")
+        full_message[1].should == "second line\n"
       end
     end
+  end
 
-    ruby_version_is "2.6" do
-      it "contains cause of exception" do
+  ruby_version_is "2.6" do
+    it "contains cause of exception" do
+      begin
         begin
-          begin
-            raise 'the cause'
-          rescue
-            raise 'main exception'
-          end
-        rescue => e
-          exception = e
+          raise 'the cause'
+        rescue
+          raise 'main exception'
         end
-
-        exception.full_message.should include "main exception"
-        exception.full_message.should include "the cause"
+      rescue => e
+        exception = e
       end
 
-      it 'contains all the chain of exceptions' do
+      exception.full_message.should include "main exception"
+      exception.full_message.should include "the cause"
+    end
+
+    it 'contains all the chain of exceptions' do
+      begin
         begin
           begin
-            begin
-              raise 'origin exception'
-            rescue
-              raise 'intermediate exception'
-            end
+            raise 'origin exception'
           rescue
-            raise 'last exception'
+            raise 'intermediate exception'
           end
-        rescue => e
-          exception = e
+        rescue
+          raise 'last exception'
         end
-
-        exception.full_message.should include "last exception"
-        exception.full_message.should include "intermediate exception"
-        exception.full_message.should include "origin exception"
+      rescue => e
+        exception = e
       end
+
+      exception.full_message.should include "last exception"
+      exception.full_message.should include "intermediate exception"
+      exception.full_message.should include "origin exception"
     end
   end
 end
diff --git a/spec/ruby/core/exception/hierarchy_spec.rb b/spec/ruby/core/exception/hierarchy_spec.rb
index e52811c761..6514eb1994 100644
--- a/spec/ruby/core/exception/hierarchy_spec.rb
+++ b/spec/ruby/core/exception/hierarchy_spec.rb
@@ -37,7 +37,9 @@ describe "Exception" do
             FloatDomainError => nil,
           },
           RegexpError => nil,
-          RuntimeError => nil,
+          RuntimeError => {
+            FrozenError => nil,
+          },
           SystemCallError => nil,
           ThreadError => nil,
           TypeError => nil,
@@ -47,9 +49,7 @@ describe "Exception" do
         SystemStackError => nil,
       },
     }
-    ruby_version_is "2.5" do
-      hierarchy[Exception][StandardError][RuntimeError] = {FrozenError => nil}
-    end
+
     traverse = -> parent_class, parent_subclass_hash {
       parent_subclass_hash.each do |child_class, child_subclass_hash|
         child_class.class.should == Class
diff --git a/spec/ruby/core/file/atime_spec.rb b/spec/ruby/core/file/atime_spec.rb
index 02e8412722..b9b5db876c 100644
--- a/spec/ruby/core/file/atime_spec.rb
+++ b/spec/ruby/core/file/atime_spec.rb
@@ -15,7 +15,7 @@ describe "File.atime" do
     File.atime(@file).should be_kind_of(Time)
   end
 
-  guard -> { platform_is :linux or (platform_is :windows and ruby_version_is '2.5') } do
+  guard -> { platform_is :linux or platform_is :windows } do
     ## NOTE also that some Linux systems disable atime (e.g. via mount params) for better filesystem speed.
     it "returns the last access time for the named file with microseconds" do
       supports_subseconds = Integer(`stat -c%x '#{__FILE__}'`[/\.(\d+)/, 1], 10)
diff --git a/spec/ruby/core/file/ctime_spec.rb b/spec/ruby/core/file/ctime_spec.rb
index 68a9fa43cb..fff74b1d40 100644
--- a/spec/ruby/core/file/ctime_spec.rb
+++ b/spec/ruby/core/file/ctime_spec.rb
@@ -14,7 +14,7 @@ describe "File.ctime" do
     File.ctime(@file).should be_kind_of(Time)
   end
 
-  guard -> { platform_is :linux or (platform_is :windows and ruby_version_is '2.5') } do
+  guard -> { platform_is :linux or platform_is :windows } do
     it "returns the change time for the named file (the time at which directory information about the file was changed, not the file itself) with microseconds." do
       supports_subseconds = Integer(`stat -c%z '#{__FILE__}'`[/\.(\d+)/, 1], 10)
       if supports_subseconds != 0
diff --git a/spec/ruby/core/file/lutime_spec.rb b/spec/ruby/core/file/lutime_spec.rb
index 7449bc4389..1f0625f61e 100644
--- a/spec/ruby/core/file/lutime_spec.rb
+++ b/spec/ruby/core/file/lutime_spec.rb
@@ -1,40 +1,38 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "File.lutime" do
-    platform_is_not :windows do
-      before :each do
-        @atime = Time.utc(2000)
-        @mtime = Time.utc(2001)
-        @file = tmp("specs_lutime_file")
-        @symlink = tmp("specs_lutime_symlink")
-        touch @file
-        File.symlink(@file, @symlink)
-      end
+describe "File.lutime" do
+  platform_is_not :windows do
+    before :each do
+      @atime = Time.utc(2000)
+      @mtime = Time.utc(2001)
+      @file = tmp("specs_lutime_file")
+      @symlink = tmp("specs_lutime_symlink")
+      touch @file
+      File.symlink(@file, @symlink)
+    end
 
-      after :each do
-        rm_r @file, @symlink
-      end
+    after :each do
+      rm_r @file, @symlink
+    end
 
-      it "sets the access and modification time for a regular file" do
-        File.lutime(@atime, @mtime, @file)
-        stat = File.stat(@file)
-        stat.atime.should == @atime
-        stat.mtime.should === @mtime
-      end
+    it "sets the access and modification time for a regular file" do
+      File.lutime(@atime, @mtime, @file)
+      stat = File.stat(@file)
+      stat.atime.should == @atime
+      stat.mtime.should === @mtime
+    end
 
-      it "sets the access and modification time for a symlink" do
-        original = File.stat(@file)
+    it "sets the access and modification time for a symlink" do
+      original = File.stat(@file)
 
-        File.lutime(@atime, @mtime, @symlink)
-        stat = File.lstat(@symlink)
-        stat.atime.should == @atime
-        stat.mtime.should === @mtime
+      File.lutime(@atime, @mtime, @symlink)
+      stat = File.lstat(@symlink)
+      stat.atime.should == @atime
+      stat.mtime.should === @mtime
 
-        file = File.stat(@file)
-        file.atime.should == original.atime
-        file.mtime.should == original.mtime
-      end
+      file = File.stat(@file)
+      file.atime.should == original.atime
+      file.mtime.should == original.mtime
     end
   end
 end
diff --git a/spec/ruby/core/file/mtime_spec.rb b/spec/ruby/core/file/mtime_spec.rb
index 1941e2ff85..02f6fc4637 100644
--- a/spec/ruby/core/file/mtime_spec.rb
+++ b/spec/ruby/core/file/mtime_spec.rb
@@ -15,7 +15,7 @@ describe "File.mtime" do
     File.mtime(@filename).should be_close(@mtime, TIME_TOLERANCE)
   end
 
-  guard -> { platform_is :linux or (platform_is :windows and ruby_version_is '2.5') } do
+  guard -> { platform_is :linux or platform_is :windows } do
     it "returns the modification Time of the file with microseconds" do
       supports_subseconds = Integer(`stat -c%y '#{__FILE__}'`[/\.(\d+)/, 1], 10)
       if supports_subseconds != 0
diff --git a/spec/ruby/core/file/open_spec.rb b/spec/ruby/core/file/open_spec.rb
index e3c5618795..7ceeb47dd8 100644
--- a/spec/ruby/core/file/open_spec.rb
+++ b/spec/ruby/core/file/open_spec.rb
@@ -623,12 +623,10 @@ describe "File.open" do
     end
   end
 
-  ruby_version_is "2.5" do
-    it "raises ArgumentError if mixing :newline and binary mode" do
-      -> {
-        File.open(@file, "rb", newline: :universal) {}
-      }.should raise_error(ArgumentError, "newline decorator with binary mode")
-    end
+  it "raises ArgumentError if mixing :newline and binary mode" do
+    -> {
+      File.open(@file, "rb", newline: :universal) {}
+    }.should raise_error(ArgumentError, "newline decorator with binary mode")
   end
 
   ruby_version_is "2.6" do
diff --git a/spec/ruby/core/file/shared/path.rb b/spec/ruby/core/file/shared/path.rb
index cfd119f799..d964acc855 100644
--- a/spec/ruby/core/file/shared/path.rb
+++ b/spec/ruby/core/file/shared/path.rb
@@ -50,26 +50,24 @@ describe :file_path, shared: true do
     @file.send(@method).encoding.should == Encoding.find("euc-jp")
   end
 
-  ruby_version_is "2.5" do
-    platform_is :linux do
-      guard -> { defined?(File::TMPFILE) } do
-        before :each do
-          @dir = tmp("tmpfilespec")
-          mkdir_p @dir
-        end
+  platform_is :linux do
+    guard -> { defined?(File::TMPFILE) } do
+      before :each do
+        @dir = tmp("tmpfilespec")
+        mkdir_p @dir
+      end
 
-        after :each do
-          rm_r @dir
-        end
+      after :each do
+        rm_r @dir
+      end
 
-        it "raises IOError if file was opened with File::TMPFILE" do
-          begin
-            File.open(@dir, File::RDWR | File::TMPFILE) do |f|
-              -> { f.send(@method) }.should raise_error(IOError)
-            end
-          rescue Errno::EOPNOTSUPP, Errno::EINVAL, Errno::EISDIR
-            skip "no support from the filesystem"
+      it "raises IOError if file was opened with File::TMPFILE" do
+        begin
+          File.open(@dir, File::RDWR | File::TMPFILE) do |f|
+            -> { f.send(@method) }.should raise_error(IOError)
           end
+        rescue Errno::EOPNOTSUPP, Errno::EINVAL, Errno::EISDIR
+          skip "no support from the filesystem"
         end
       end
     end
diff --git a/spec/ruby/core/float/comparison_spec.rb b/spec/ruby/core/float/comparison_spec.rb
index 2dc993a176..51bb5a52db 100644
--- a/spec/ruby/core/float/comparison_spec.rb
+++ b/spec/ruby/core/float/comparison_spec.rb
@@ -33,19 +33,17 @@ describe "Float#<=>" do
     coercible.call_count.should == 3
   end
 
-  ruby_version_is "2.5" do
-    it "raises TypeError when #coerce misbehaves" do
-      klass = Class.new do
-        def coerce(other)
-          :incorrect
-        end
+  it "raises TypeError when #coerce misbehaves" do
+    klass = Class.new do
+      def coerce(other)
+        :incorrect
       end
-
-      bad_coercible = klass.new
-      -> {
-        4.2 <=> bad_coercible
-      }.should raise_error(TypeError, "coerce must return [x, y]")
     end
+
+    bad_coercible = klass.new
+    -> {
+      4.2 <=> bad_coercible
+    }.should raise_error(TypeError, "coerce must return [x, y]")
   end
 
   # The 4 tests below are taken from matz's revision 23730 for Ruby trunk
diff --git a/spec/ruby/core/float/shared/arithmetic_exception_in_coerce.rb b/spec/ruby/core/float/shared/arithmetic_exception_in_coerce.rb
index 19a02572d8..eec92d858f 100644
--- a/spec/ruby/core/float/shared/arithmetic_exception_in_coerce.rb
+++ b/spec/ruby/core/float/shared/arithmetic_exception_in_coerce.rb
@@ -1,33 +1,11 @@
 require_relative '../fixtures/classes'
 
 describe :float_arithmetic_exception_in_coerce, shared: true do
-  ruby_version_is ""..."2.5" do
-    it "rescues exception (StandardError and subclasses) raised in other#coerce and raises TypeError" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
+  it "does not rescue exception raised in other#coerce" do
+    b = mock("numeric with failed #coerce")
+    b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
 
-      # e.g. 1.0 > b
-      -> { 1.0.send(@method, b) }.should raise_error(TypeError, /MockObject can't be coerced into Float/)
-    end
-
-    it "does not rescue Exception and StandardError siblings raised in other#coerce" do
-      [Exception, NoMemoryError].each do |exception|
-        b = mock("numeric with failed #coerce")
-        b.should_receive(:coerce).and_raise(exception)
-
-        # e.g. 1.0 > b
-        -> { 1.0.send(@method, b) }.should raise_error(exception)
-      end
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not rescue exception raised in other#coerce" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
-
-      # e.g. 1.0 > b
-      -> { 1.0.send(@method, b) }.should raise_error(FloatSpecs::CoerceError)
-    end
+    # e.g. 1.0 > b
+    -> { 1.0.send(@method, b) }.should raise_error(FloatSpecs::CoerceError)
   end
 end
diff --git a/spec/ruby/core/float/shared/comparison_exception_in_coerce.rb b/spec/ruby/core/float/shared/comparison_exception_in_coerce.rb
index f8ded53644..3e2c1e28dd 100644
--- a/spec/ruby/core/float/shared/comparison_exception_in_coerce.rb
+++ b/spec/ruby/core/float/shared/comparison_exception_in_coerce.rb
@@ -1,35 +1,11 @@
 require_relative '../fixtures/classes'
 
 describe :float_comparison_exception_in_coerce, shared: true do
-  ruby_version_is ""..."2.5" do
-    it "rescues exception (StandardError and subclasses) raised in other#coerce and raises ArgumentError" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
+  it "does not rescue exception raised in other#coerce" do
+    b = mock("numeric with failed #coerce")
+    b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
 
-      # e.g. 1.0 > b
-      -> {
-        -> { 1.0.send(@method, b) }.should raise_error(ArgumentError, /comparison of Float with MockObject failed/)
-      }.should complain(/Numerical comparison operators will no more rescue exceptions of #coerce/)
-    end
-
-    it "does not rescue Exception and StandardError siblings raised in other#coerce" do
-      [Exception, NoMemoryError].each do |exception|
-        b = mock("numeric with failed #coerce")
-        b.should_receive(:coerce).and_raise(exception)
-
-        # e.g. 1.0 > b
-        -> { 1.0.send(@method, b) }.should raise_error(exception)
-      end
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not rescue exception raised in other#coerce" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(FloatSpecs::CoerceError)
-
-      # e.g. 1.0 > b
-      -> { 1.0.send(@method, b) }.should raise_error(FloatSpecs::CoerceError)
-    end
+    # e.g. 1.0 > b
+    -> { 1.0.send(@method, b) }.should raise_error(FloatSpecs::CoerceError)
   end
 end
diff --git a/spec/ruby/core/hash/slice_spec.rb b/spec/ruby/core/hash/slice_spec.rb
index f7717c9404..e3046d83d7 100644
--- a/spec/ruby/core/hash/slice_spec.rb
+++ b/spec/ruby/core/hash/slice_spec.rb
@@ -1,55 +1,53 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Hash#slice" do
-    before :each do
-      @hash = { a: 1, b: 2, c: 3 }
-    end
+describe "Hash#slice" do
+  before :each do
+    @hash = { a: 1, b: 2, c: 3 }
+  end
 
-    it "returns a new empty hash without arguments" do
-      ret = @hash.slice
-      ret.should_not equal(@hash)
-      ret.should be_an_instance_of(Hash)
-      ret.should == {}
-    end
+  it "returns a new empty hash without arguments" do
+    ret = @hash.slice
+    ret.should_not equal(@hash)
+    ret.should be_an_instance_of(Hash)
+    ret.should == {}
+  end
 
-    it "returns the requested subset" do
-      @hash.slice(:c, :a).should == { c: 3, a: 1 }
-    end
+  it "returns the requested subset" do
+    @hash.slice(:c, :a).should == { c: 3, a: 1 }
+  end
 
-    it "returns a hash ordered in the order of the requested keys" do
-      @hash.slice(:c, :a).keys.should == [:c, :a]
-    end
+  it "returns a hash ordered in the order of the requested keys" do
+    @hash.slice(:c, :a).keys.should == [:c, :a]
+  end
 
-    it "returns only the keys of the original hash" do
-      @hash.slice(:a, :chunky_bacon).should == { a: 1 }
-    end
+  it "returns only the keys of the original hash" do
+    @hash.slice(:a, :chunky_bacon).should == { a: 1 }
+  end
 
-    it "returns a Hash instance, even on subclasses" do
-      klass = Class.new(Hash)
-      h = klass.new
-      h[:bar] = 12
-      h[:foo] = 42
-      r = h.slice(:foo)
-      r.should == {foo: 42}
-      r.class.should == Hash
-    end
+  it "returns a Hash instance, even on subclasses" do
+    klass = Class.new(Hash)
+    h = klass.new
+    h[:bar] = 12
+    h[:foo] = 42
+    r = h.slice(:foo)
+    r.should == {foo: 42}
+    r.class.should == Hash
+  end
 
-    it "uses the regular Hash#[] method, even on subclasses that override it" do
-      ScratchPad.record []
-      klass = Class.new(Hash) do
-        def [](value)
-          ScratchPad << :used_subclassed_operator
-          super
-        end
+  it "uses the regular Hash#[] method, even on subclasses that override it" do
+    ScratchPad.record []
+    klass = Class.new(Hash) do
+      def [](value)
+        ScratchPad << :used_subclassed_operator
+        super
       end
+    end
 
-      h = klass.new
-      h[:bar] = 12
-      h[:foo] = 42
-      h.slice(:foo)
+    h = klass.new
+    h[:bar] = 12
+    h[:foo] = 42
+    h.slice(:foo)
 
-      ScratchPad.recorded.should == []
-    end
+    ScratchPad.recorded.should == []
   end
 end
diff --git a/spec/ruby/core/hash/transform_keys_spec.rb b/spec/ruby/core/hash/transform_keys_spec.rb
index 956fd73a47..2c5d4124e0 100644
--- a/spec/ruby/core/hash/transform_keys_spec.rb
+++ b/spec/ruby/core/hash/transform_keys_spec.rb
@@ -1,131 +1,129 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Hash#transform_keys" do
-    before :each do
-      @hash = { a: 1, b: 2, c: 3 }
-    end
+describe "Hash#transform_keys" do
+  before :each do
+    @hash = { a: 1, b: 2, c: 3 }
+  end
 
-    it "returns new hash" do
-      ret = @hash.transform_keys(&:succ)
-      ret.should_not equal(@hash)
-      ret.should be_an_instance_of(Hash)
-    end
+  it "returns new hash" do
+    ret = @hash.transform_keys(&:succ)
+    ret.should_not equal(@hash)
+    ret.should be_an_instance_of(Hash)
+  end
 
-    it "sets the result as transformed keys with the given block" do
-      @hash.transform_keys(&:succ).should ==  { b: 1, c: 2, d: 3 }
-    end
+  it "sets the result as transformed keys with the given block" do
+    @hash.transform_keys(&:succ).should ==  { b: 1, c: 2, d: 3 }
+  end
 
-    it "keeps last pair if new keys conflict" do
-      @hash.transform_keys { |_| :a }.should == { a: 3 }
-    end
+  it "keeps last pair if new keys conflict" do
+    @hash.transform_keys { |_| :a }.should == { a: 3 }
+  end
 
-    it "makes both hashes to share values" do
-      value = [1, 2, 3]
-      new_hash = { a: value }.transform_keys(&:upcase)
-      new_hash[:A].should equal(value)
-    end
+  it "makes both hashes to share values" do
+    value = [1, 2, 3]
+    new_hash = { a: value }.transform_keys(&:upcase)
+    new_hash[:A].should equal(value)
+  end
 
-    context "when no block is given" do
-      it "returns a sized Enumerator" do
-        enumerator = @hash.transform_keys
-        enumerator.should be_an_instance_of(Enumerator)
-        enumerator.size.should == @hash.size
-        enumerator.each(&:succ).should == { b: 1, c: 2, d: 3 }
-      end
+  context "when no block is given" do
+    it "returns a sized Enumerator" do
+      enumerator = @hash.transform_keys
+      enumerator.should be_an_instance_of(Enumerator)
+      enumerator.size.should == @hash.size
+      enumerator.each(&:succ).should == { b: 1, c: 2, d: 3 }
     end
+  end
 
-    it "returns a Hash instance, even on subclasses" do
-      klass = Class.new(Hash)
-      h = klass.new
-      h[:foo] = 42
-      r = h.transform_keys{|v| :"x#{v}"}
-      r.keys.should == [:xfoo]
-      r.class.should == Hash
-    end
+  it "returns a Hash instance, even on subclasses" do
+    klass = Class.new(Hash)
+    h = klass.new
+    h[:foo] = 42
+    r = h.transform_keys{|v| :"x#{v}"}
+    r.keys.should == [:xfoo]
+    r.class.should == Hash
   end
+end
 
-  describe "Hash#transform_keys!" do
-    before :each do
-      @hash = { a: 1, b: 2, c: 3, d: 4 }
-      @initial_pairs = @hash.dup
-    end
+describe "Hash#transform_keys!" do
+  before :each do
+    @hash = { a: 1, b: 2, c: 3, d: 4 }
+    @initial_pairs = @hash.dup
+  end
 
-    it "returns self" do
-      @hash.transform_keys!(&:succ).should equal(@hash)
-    end
+  it "returns self" do
+    @hash.transform_keys!(&:succ).should equal(@hash)
+  end
 
-    it "updates self as transformed values with the given block" do
-      @hash.transform_keys!(&:to_s)
-      @hash.should == { 'a' => 1, 'b' => 2, 'c' => 3, 'd' => 4 }
-    end
+  it "updates self as transformed values with the given block" do
+    @hash.transform_keys!(&:to_s)
+    @hash.should == { 'a' => 1, 'b' => 2, 'c' => 3, 'd' => 4 }
+  end
 
-    # https://bugs.ruby-lang.org/issues/14380
-    ruby_version_is ""..."2.5.1" do
-      it "does not prevent conflicts between new keys and old ones" do
-        @hash.transform_keys!(&:succ)
-        @hash.should == { e: 1 }
-      end
+  # https://bugs.ruby-lang.org/issues/14380
+  ruby_version_is ""..."2.5.1" do
+    it "does not prevent conflicts between new keys and old ones" do
+      @hash.transform_keys!(&:succ)
+      @hash.should == { e: 1 }
     end
+  end
 
-    ruby_version_is "2.5.1" do
-      it "prevents conflicts between new keys and old ones" do
-        @hash.transform_keys!(&:succ)
-        @hash.should == { b: 1, c: 2, d: 3, e: 4 }
-      end
+  ruby_version_is "2.5.1" do
+    it "prevents conflicts between new keys and old ones" do
+      @hash.transform_keys!(&:succ)
+      @hash.should == { b: 1, c: 2, d: 3, e: 4 }
     end
+  end
 
-    ruby_version_is ""..."2.5.1" do
-      it "partially modifies the contents if we broke from the block" do
-        @hash.transform_keys! do |v|
-          break if v == :c
-          v.succ
-        end
-        @hash.should == { c: 1, d: 4 }
+  ruby_version_is ""..."2.5.1" do
+    it "partially modifies the contents if we broke from the block" do
+      @hash.transform_keys! do |v|
+        break if v == :c
+        v.succ
       end
+      @hash.should == { c: 1, d: 4 }
     end
+  end
 
-    ruby_version_is "2.5.1" do
-      it "returns the processed keys if we broke from the block" do
-        @hash.transform_keys! do |v|
-          break if v == :c
-          v.succ
-        end
-        @hash.should == { b: 1, c: 2 }
+  ruby_version_is "2.5.1" do
+    it "returns the processed keys if we broke from the block" do
+      @hash.transform_keys! do |v|
+        break if v == :c
+        v.succ
       end
+      @hash.should == { b: 1, c: 2 }
     end
+  end
 
-    it "keeps later pair if new keys conflict" do
-      @hash.transform_keys! { |_| :a }.should == { a: 4 }
-    end
+  it "keeps later pair if new keys conflict" do
+    @hash.transform_keys! { |_| :a }.should == { a: 4 }
+  end
 
-    context "when no block is given" do
-      it "returns a sized Enumerator" do
-        enumerator = @hash.transform_keys!
-        enumerator.should be_an_instance_of(Enumerator)
-        enumerator.size.should == @hash.size
-        enumerator.each(&:upcase).should == { A: 1, B: 2, C: 3, D: 4 }
-      end
+  context "when no block is given" do
+    it "returns a sized Enumerator" do
+      enumerator = @hash.transform_keys!
+      enumerator.should be_an_instance_of(Enumerator)
+      enumerator.size.should == @hash.size
+      enumerator.each(&:upcase).should == { A: 1, B: 2, C: 3, D: 4 }
     end
+  end
 
-    describe "on frozen instance" do
-      before :each do
-        @hash.freeze
-      end
+  describe "on frozen instance" do
+    before :each do
+      @hash.freeze
+    end
 
-      it "raises a FrozenError on an empty hash" do
-        ->{ {}.freeze.transform_keys!(&:upcase) }.should raise_error(FrozenError)
-      end
+    it "raises a FrozenError on an empty hash" do
+      ->{ {}.freeze.transform_keys!(&:upcase) }.should raise_error(FrozenError)
+    end
 
-      it "keeps pairs and raises a FrozenError" do
-        ->{ @hash.transform_keys!(&:upcase) }.should raise_error(FrozenError)
-        @hash.should == @initial_pairs
-      end
+    it "keeps pairs and raises a FrozenError" do
+      ->{ @hash.transform_keys!(&:upcase) }.should raise_error(FrozenError)
+      @hash.should == @initial_pairs
+    end
 
-      context "when no block is given" do
-        it "does not raise an exception" do
-          @hash.transform_keys!.should be_an_instance_of(Enumerator)
-        end
+    context "when no block is given" do
+      it "does not raise an exception" do
+        @hash.transform_keys!.should be_an_instance_of(Enumerator)
       end
     end
   end
diff --git a/spec/ruby/core/integer/allbits_spec.rb b/spec/ruby/core/integer/allbits_spec.rb
index f4a6fe9905..11acb52e1f 100644
--- a/spec/ruby/core/integer/allbits_spec.rb
+++ b/spec/ruby/core/integer/allbits_spec.rb
@@ -1,39 +1,37 @@
 require_relative '../../spec_helper'
 
-ruby_version_is '2.5' do
-  describe "Integer#allbits?" do
-    it "returns true iff all the bits of the argument are set in the receiver" do
-      42.allbits?(42).should == true
-      0b1010_1010.allbits?(0b1000_0010).should == true
-      0b1010_1010.allbits?(0b1000_0001).should == false
-      0b1000_0010.allbits?(0b1010_1010).should == false
-      (0b1010_1010 | bignum_value).allbits?(0b1000_0010 | bignum_value).should == true
-      (0b1010_1010 | bignum_value).allbits?(0b1000_0001 | bignum_value).should == false
-      (0b1000_0010 | bignum_value).allbits?(0b1010_1010 | bignum_value).should == false
-    end
+describe "Integer#allbits?" do
+  it "returns true iff all the bits of the argument are set in the receiver" do
+    42.allbits?(42).should == true
+    0b1010_1010.allbits?(0b1000_0010).should == true
+    0b1010_1010.allbits?(0b1000_0001).should == false
+    0b1000_0010.allbits?(0b1010_1010).should == false
+    (0b1010_1010 | bignum_value).allbits?(0b1000_0010 | bignum_value).should == true
+    (0b1010_1010 | bignum_value).allbits?(0b1000_0001 | bignum_value).should == false
+    (0b1000_0010 | bignum_value).allbits?(0b1010_1010 | bignum_value).should == false
+  end
 
-    it "handles negative values using two's complement notation" do
-      (~0b1).allbits?(42).should == true
-      (-42).allbits?(-42).should == true
-      (~0b1010_1010).allbits?(~0b1110_1011).should == true
-      (~0b1010_1010).allbits?(~0b1000_0010).should == false
-      (~(0b1010_1010 | bignum_value)).allbits?(~(0b1110_1011 | bignum_value)).should == true
-      (~(0b1010_1010 | bignum_value)).allbits?(~(0b1000_0010 | bignum_value)).should == false
-    end
+  it "handles negative values using two's complement notation" do
+    (~0b1).allbits?(42).should == true
+    (-42).allbits?(-42).should == true
+    (~0b1010_1010).allbits?(~0b1110_1011).should == true
+    (~0b1010_1010).allbits?(~0b1000_0010).should == false
+    (~(0b1010_1010 | bignum_value)).allbits?(~(0b1110_1011 | bignum_value)).should == true
+    (~(0b1010_1010 | bignum_value)).allbits?(~(0b1000_0010 | bignum_value)).should == false
+  end
 
-    it "coerces the rhs using to_int" do
-      obj = mock("the int 0b10")
-      obj.should_receive(:to_int).and_return(0b10)
-      0b110.allbits?(obj).should == true
-    end
+  it "coerces the rhs using to_int" do
+    obj = mock("the int 0b10")
+    obj.should_receive(:to_int).and_return(0b10)
+    0b110.allbits?(obj).should == true
+  end
 
-    it "raises a TypeError when given a non-Integer" do
-      -> {
-        (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
-        13.allbits?(obj)
-      }.should raise_error(TypeError)
-      -> { 13.allbits?("10")    }.should raise_error(TypeError)
-      -> { 13.allbits?(:symbol) }.should raise_error(TypeError)
-    end
+  it "raises a TypeError when given a non-Integer" do
+    -> {
+      (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
+      13.allbits?(obj)
+    }.should raise_error(TypeError)
+    -> { 13.allbits?("10")    }.should raise_error(TypeError)
+    -> { 13.allbits?(:symbol) }.should raise_error(TypeError)
   end
 end
diff --git a/spec/ruby/core/integer/anybits_spec.rb b/spec/ruby/core/integer/anybits_spec.rb
index 91f349258a..7e510fd00b 100644
--- a/spec/ruby/core/integer/anybits_spec.rb
+++ b/spec/ruby/core/integer/anybits_spec.rb
@@ -1,38 +1,36 @@
 require_relative '../../spec_helper'
 
-ruby_version_is '2.5' do
-  describe "Integer#anybits?" do
-    it "returns true iff all the bits of the argument are set in the receiver" do
-      42.anybits?(42).should == true
-      0b1010_1010.anybits?(0b1000_0010).should == true
-      0b1010_1010.anybits?(0b1000_0001).should == true
-      0b1000_0010.anybits?(0b0010_1100).should == false
-      different_bignum = (2 * bignum_value) & (~bignum_value)
-      (0b1010_1010 | different_bignum).anybits?(0b1000_0010 | bignum_value).should == true
-      (0b1010_1010 | different_bignum).anybits?(0b0010_1100 | bignum_value).should == true
-      (0b1000_0010 | different_bignum).anybits?(0b0010_1100 | bignum_value).should == false
-    end
+describe "Integer#anybits?" do
+  it "returns true iff all the bits of the argument are set in the receiver" do
+    42.anybits?(42).should == true
+    0b1010_1010.anybits?(0b1000_0010).should == true
+    0b1010_1010.anybits?(0b1000_0001).should == true
+    0b1000_0010.anybits?(0b0010_1100).should == false
+    different_bignum = (2 * bignum_value) & (~bignum_value)
+    (0b1010_1010 | different_bignum).anybits?(0b1000_0010 | bignum_value).should == true
+    (0b1010_1010 | different_bignum).anybits?(0b0010_1100 | bignum_value).should == true
+    (0b1000_0010 | different_bignum).anybits?(0b0010_1100 | bignum_value).should == false
+  end
 
-    it "handles negative values using two's complement notation" do
-      (~42).anybits?(42).should == false
-      (-42).anybits?(-42).should == true
-      (~0b100).anybits?(~0b1).should == true
-      (~(0b100 | bignum_value)).anybits?(~(0b1 | bignum_value)).should == true
-    end
+  it "handles negative values using two's complement notation" do
+    (~42).anybits?(42).should == false
+    (-42).anybits?(-42).should == true
+    (~0b100).anybits?(~0b1).should == true
+    (~(0b100 | bignum_value)).anybits?(~(0b1 | bignum_value)).should == true
+  end
 
-    it "coerces the rhs using to_int" do
-      obj = mock("the int 0b10")
-      obj.should_receive(:to_int).and_return(0b10)
-      0b110.anybits?(obj).should == true
-    end
+  it "coerces the rhs using to_int" do
+    obj = mock("the int 0b10")
+    obj.should_receive(:to_int).and_return(0b10)
+    0b110.anybits?(obj).should == true
+  end
 
-    it "raises a TypeError when given a non-Integer" do
-      -> {
-        (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
-        13.anybits?(obj)
-      }.should raise_error(TypeError)
-      -> { 13.anybits?("10")    }.should raise_error(TypeError)
-      -> { 13.anybits?(:symbol) }.should raise_error(TypeError)
-    end
+  it "raises a TypeError when given a non-Integer" do
+    -> {
+      (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
+      13.anybits?(obj)
+    }.should raise_error(TypeError)
+    -> { 13.anybits?("10")    }.should raise_error(TypeError)
+    -> { 13.anybits?(:symbol) }.should raise_error(TypeError)
   end
 end
diff --git a/spec/ruby/core/integer/comparison_spec.rb b/spec/ruby/core/integer/comparison_spec.rb
index 2ff557c7c6..db050aa8b9 100644
--- a/spec/ruby/core/integer/comparison_spec.rb
+++ b/spec/ruby/core/integer/comparison_spec.rb
@@ -124,23 +124,11 @@ describe "Integer#<=>" do
         @big <=> @num
       end
 
-      ruby_version_is ""..."2.5" do
-        it "returns nil if #coerce raises an exception" do
-          @num.should_receive(:coerce).with(@big).and_raise(RuntimeError)
-          -> {
-            @result = (@big <=> @num)
-          }.should complain(/Numerical comparison operators will no more rescue exceptions/)
-          @result.should be_nil
-        end
-      end
-
-      ruby_version_is "2.5" do
-        it "lets the exception go through if #coerce raises an exception" do
-          @num.should_receive(:coerce).with(@big).and_raise(RuntimeError.new("my error"))
-          -> {
-            @big <=> @num
-          }.should raise_error(RuntimeError, "my error")
-        end
+      it "lets the exception go through if #coerce raises an exception" do
+        @num.should_receive(:coerce).with(@big).and_raise(RuntimeError.new("my error"))
+        -> {
+          @big <=> @num
+        }.should raise_error(RuntimeError, "my error")
       end
 
       it "raises an exception if #coerce raises a non-StandardError exception" do
diff --git a/spec/ruby/core/integer/divide_spec.rb b/spec/ruby/core/integer/divide_spec.rb
index a32d68c229..5ac2dc538d 100644
--- a/spec/ruby/core/integer/divide_spec.rb
+++ b/spec/ruby/core/integer/divide_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/arithmetic_coerce'
 
 describe "Integer#/" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_arithmetic_coerce_rescue, :/
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_arithmetic_coerce_not_rescue, :/
-  end
+  it_behaves_like :integer_arithmetic_coerce_not_rescue, :/
 
   context "fixnum" do
     it "returns self divided by the given argument" do
diff --git a/spec/ruby/core/integer/gt_spec.rb b/spec/ruby/core/integer/gt_spec.rb
index 428a6f6888..f0179e566d 100644
--- a/spec/ruby/core/integer/gt_spec.rb
+++ b/spec/ruby/core/integer/gt_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/comparison_coerce'
 
 describe "Integer#>" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_comparison_coerce_rescue, :>
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_comparison_coerce_not_rescue, :>
-  end
+  it_behaves_like :integer_comparison_coerce_not_rescue, :>
 
   context "fixnum" do
     it "returns true if self is greater than the given argument" do
diff --git a/spec/ruby/core/integer/gte_spec.rb b/spec/ruby/core/integer/gte_spec.rb
index ce1385c360..6237fc2c51 100644
--- a/spec/ruby/core/integer/gte_spec.rb
+++ b/spec/ruby/core/integer/gte_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/comparison_coerce'
 
 describe "Integer#>=" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_comparison_coerce_rescue, :>=
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_comparison_coerce_not_rescue, :>=
-  end
+  it_behaves_like :integer_comparison_coerce_not_rescue, :>=
 
   context "fixnum" do
     it "returns true if self is greater than or equal to the given argument" do
diff --git a/spec/ruby/core/integer/lt_spec.rb b/spec/ruby/core/integer/lt_spec.rb
index dfe2d9e369..c182f82555 100644
--- a/spec/ruby/core/integer/lt_spec.rb
+++ b/spec/ruby/core/integer/lt_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/comparison_coerce'
 
 describe "Integer#<" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_comparison_coerce_rescue, :<
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_comparison_coerce_not_rescue, :<
-  end
+  it_behaves_like :integer_comparison_coerce_not_rescue, :<
 
   context "fixnum" do
     it "returns true if self is less than the given argument" do
diff --git a/spec/ruby/core/integer/lte_spec.rb b/spec/ruby/core/integer/lte_spec.rb
index 40a89f094a..65b71d77f2 100644
--- a/spec/ruby/core/integer/lte_spec.rb
+++ b/spec/ruby/core/integer/lte_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/comparison_coerce'
 
 describe "Integer#<=" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_comparison_coerce_rescue, :<=
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_comparison_coerce_not_rescue, :<=
-  end
+  it_behaves_like :integer_comparison_coerce_not_rescue, :<=
 
   context "fixnum" do
     it "returns true if self is less than or equal to other" do
diff --git a/spec/ruby/core/integer/minus_spec.rb b/spec/ruby/core/integer/minus_spec.rb
index 34dd36c1a7..ce50c8752f 100644
--- a/spec/ruby/core/integer/minus_spec.rb
+++ b/spec/ruby/core/integer/minus_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/arithmetic_coerce'
 
 describe "Integer#-" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_arithmetic_coerce_rescue, :-
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_arithmetic_coerce_not_rescue, :-
-  end
+  it_behaves_like :integer_arithmetic_coerce_not_rescue, :-
 
   context "fixnum" do
     it "returns self minus the given Integer" do
diff --git a/spec/ruby/core/integer/multiply_spec.rb b/spec/ruby/core/integer/multiply_spec.rb
index 919786cbcc..d1e9c2640d 100644
--- a/spec/ruby/core/integer/multiply_spec.rb
+++ b/spec/ruby/core/integer/multiply_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/arithmetic_coerce'
 
 describe "Integer#*" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_arithmetic_coerce_rescue, :*
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_arithmetic_coerce_not_rescue, :*
-  end
+  it_behaves_like :integer_arithmetic_coerce_not_rescue, :*
 
   context "fixnum" do
     it "returns self multiplied by the given Integer" do
diff --git a/spec/ruby/core/integer/nobits_spec.rb b/spec/ruby/core/integer/nobits_spec.rb
index af3b9e7db0..b132a4a724 100644
--- a/spec/ruby/core/integer/nobits_spec.rb
+++ b/spec/ruby/core/integer/nobits_spec.rb
@@ -1,38 +1,36 @@
 require_relative '../../spec_helper'
 
-ruby_version_is '2.5' do
-  describe "Integer#nobits?" do
-    it "returns true iff all no bits of the argument are set in the receiver" do
-      42.nobits?(42).should == false
-      0b1010_1010.nobits?(0b1000_0010).should == false
-      0b1010_1010.nobits?(0b1000_0001).should == false
-      0b0100_0101.nobits?(0b1010_1010).should == true
-      different_bignum = (2 * bignum_value) & (~bignum_value)
-      (0b1010_1010 | different_bignum).nobits?(0b1000_0010 | bignum_value).should == false
-      (0b1010_1010 | different_bignum).nobits?(0b1000_0001 | bignum_value).should == false
-      (0b0100_0101 | different_bignum).nobits?(0b1010_1010 | bignum_value).should == true
-    end
+describe "Integer#nobits?" do
+  it "returns true iff all no bits of the argument are set in the receiver" do
+    42.nobits?(42).should == false
+    0b1010_1010.nobits?(0b1000_0010).should == false
+    0b1010_1010.nobits?(0b1000_0001).should == false
+    0b0100_0101.nobits?(0b1010_1010).should == true
+    different_bignum = (2 * bignum_value) & (~bignum_value)
+    (0b1010_1010 | different_bignum).nobits?(0b1000_0010 | bignum_value).should == false
+    (0b1010_1010 | different_bignum).nobits?(0b1000_0001 | bignum_value).should == false
+    (0b0100_0101 | different_bignum).nobits?(0b1010_1010 | bignum_value).should == true
+  end
 
-    it "handles negative values using two's complement notation" do
-      (~0b1101).nobits?(0b1101).should == true
-      (-42).nobits?(-42).should == false
-      (~0b1101).nobits?(~0b10).should == false
-      (~(0b1101 | bignum_value)).nobits?(~(0b10 | bignum_value)).should == false
-    end
+  it "handles negative values using two's complement notation" do
+    (~0b1101).nobits?(0b1101).should == true
+    (-42).nobits?(-42).should == false
+    (~0b1101).nobits?(~0b10).should == false
+    (~(0b1101 | bignum_value)).nobits?(~(0b10 | bignum_value)).should == false
+  end
 
-    it "coerces the rhs using to_int" do
-      obj = mock("the int 0b10")
-      obj.should_receive(:to_int).and_return(0b10)
-      0b110.nobits?(obj).should == false
-    end
+  it "coerces the rhs using to_int" do
+    obj = mock("the int 0b10")
+    obj.should_receive(:to_int).and_return(0b10)
+    0b110.nobits?(obj).should == false
+  end
 
-    it "raises a TypeError when given a non-Integer" do
-      -> {
-        (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
-        13.nobits?(obj)
-      }.should raise_error(TypeError)
-      -> { 13.nobits?("10")    }.should raise_error(TypeError)
-      -> { 13.nobits?(:symbol) }.should raise_error(TypeError)
-    end
+  it "raises a TypeError when given a non-Integer" do
+    -> {
+      (obj = mock('10')).should_receive(:coerce).any_number_of_times.and_return([42,10])
+      13.nobits?(obj)
+    }.should raise_error(TypeError)
+    -> { 13.nobits?("10")    }.should raise_error(TypeError)
+    -> { 13.nobits?(:symbol) }.should raise_error(TypeError)
   end
 end
diff --git a/spec/ruby/core/integer/plus_spec.rb b/spec/ruby/core/integer/plus_spec.rb
index 7e919a16db..be626c3305 100644
--- a/spec/ruby/core/integer/plus_spec.rb
+++ b/spec/ruby/core/integer/plus_spec.rb
@@ -2,13 +2,7 @@ require_relative '../../spec_helper'
 require_relative 'shared/arithmetic_coerce'
 
 describe "Integer#+" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_arithmetic_coerce_rescue, :+
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_arithmetic_coerce_not_rescue, :+
-  end
+  it_behaves_like :integer_arithmetic_coerce_not_rescue, :+
 
   context "fixnum" do
     it "returns self plus the given Integer" do
diff --git a/spec/ruby/core/integer/pow_spec.rb b/spec/ruby/core/integer/pow_spec.rb
index ed14c40a27..f3fb1da916 100644
--- a/spec/ruby/core/integer/pow_spec.rb
+++ b/spec/ruby/core/integer/pow_spec.rb
@@ -2,48 +2,46 @@ require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 require_relative 'shared/exponent'
 
-ruby_version_is "2.5" do
-  describe "Integer#pow" do
-    context "one argument is passed" do
-      it_behaves_like :integer_exponent, :pow
-    end
+describe "Integer#pow" do
+  context "one argument is passed" do
+    it_behaves_like :integer_exponent, :pow
+  end
 
-    context "two arguments are passed" do
-      it "returns modulo of self raised to the given power" do
-        2.pow(5, 12).should == 8
-        2.pow(6, 13).should == 12
-        2.pow(7, 14).should == 2
-        2.pow(8, 15).should == 1
-      end
+  context "two arguments are passed" do
+    it "returns modulo of self raised to the given power" do
+      2.pow(5, 12).should == 8
+      2.pow(6, 13).should == 12
+      2.pow(7, 14).should == 2
+      2.pow(8, 15).should == 1
+    end
 
-      it "works well with bignums" do
-        2.pow(61, 5843009213693951).should eql 3697379018277258
-        2.pow(62, 5843009213693952).should eql 1551748822859776
-        2.pow(63, 5843009213693953).should eql 3103497645717974
-        2.pow(64, 5843009213693954).should eql  363986077738838
-      end
+    it "works well with bignums" do
+      2.pow(61, 5843009213693951).should eql 3697379018277258
+      2.pow(62, 5843009213693952).should eql 1551748822859776
+      2.pow(63, 5843009213693953).should eql 3103497645717974
+      2.pow(64, 5843009213693954).should eql  363986077738838
+    end
 
-      it "handles sign like #divmod does" do
-         2.pow(5,  12).should ==  8
-         2.pow(5, -12).should == -4
-        -2.pow(5,  12).should ==  4
-        -2.pow(5, -12).should == -8
-      end
+    it "handles sign like #divmod does" do
+      2.pow(5,  12).should ==  8
+      2.pow(5, -12).should == -4
+      -2.pow(5,  12).should ==  4
+      -2.pow(5, -12).should == -8
+    end
 
-      it "ensures all arguments are integers" do
-        -> { 2.pow(5, 12.0) }.should raise_error(TypeError, /2nd argument not allowed unless all arguments are integers/)
-        -> { 2.pow(5, Rational(12, 1)) }.should raise_error(TypeError, /2nd argument not allowed unless all arguments are integers/)
-      end
+    it "ensures all arguments are integers" do
+      -> { 2.pow(5, 12.0) }.should raise_error(TypeError, /2nd argument not allowed unless all arguments are integers/)
+      -> { 2.pow(5, Rational(12, 1)) }.should raise_error(TypeError, /2nd argument not allowed unless all arguments are integers/)
+    end
 
-      it "raises TypeError for non-numeric value" do
-        -> { 2.pow(5, "12") }.should raise_error(TypeError)
-        -> { 2.pow(5, []) }.should raise_error(TypeError)
-        -> { 2.pow(5, nil) }.should raise_error(TypeError)
-      end
+    it "raises TypeError for non-numeric value" do
+      -> { 2.pow(5, "12") }.should raise_error(TypeError)
+      -> { 2.pow(5, []) }.should raise_error(TypeError)
+      -> { 2.pow(5, nil) }.should raise_error(TypeError)
+    end
 
-      it "raises a ZeroDivisionError when the given argument is 0" do
-        -> { 2.pow(5, 0) }.should raise_error(ZeroDivisionError)
-      end
+    it "raises a ZeroDivisionError when the given argument is 0" do
+      -> { 2.pow(5, 0) }.should raise_error(ZeroDivisionError)
     end
   end
 end
diff --git a/spec/ruby/core/integer/round_spec.rb b/spec/ruby/core/integer/round_spec.rb
index feb6d475d3..45ac126fd3 100644
--- a/spec/ruby/core/integer/round_spec.rb
+++ b/spec/ruby/core/integer/round_spec.rb
@@ -6,14 +6,6 @@ describe "Integer#round" do
   it_behaves_like :integer_to_i, :round
   it_behaves_like :integer_rounding_positive_precision, :round
 
-  ruby_version_is ""..."2.5" do # Not just since 2.4
-    it "rounds itself as a float if passed a positive precision" do
-      [2, -4, 10**70, -10**100].each do |v|
-        v.round(42).should eql(v.to_f)
-      end
-    end
-  end
-
   # redmine:5228
   it "returns itself rounded if passed a negative value" do
     +249.round(-2).should eql(+200)
@@ -78,20 +70,10 @@ describe "Integer#round" do
     (-25).round(-1, half: nil).should   eql(-30)
   end
 
-  ruby_version_is "2.4"..."2.5" do
-    it "returns itself as a float if passed a positive precision and the half option" do
-      35.round(1, half: :up).should      eql(35.0)
-      35.round(1, half: :down).should    eql(35.0)
-      35.round(1, half: :even).should    eql(35.0)
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns itself if passed a positive precision and the half option" do
-      35.round(1, half: :up).should      eql(35)
-      35.round(1, half: :down).should    eql(35)
-      35.round(1, half: :even).should    eql(35)
-    end
+  it "returns itself if passed a positive precision and the half option" do
+    35.round(1, half: :up).should      eql(35)
+    35.round(1, half: :down).should    eql(35)
+    35.round(1, half: :even).should    eql(35)
   end
 
   it "raises ArgumentError for an unknown rounding mode" do
diff --git a/spec/ruby/core/integer/shared/arithmetic_coerce.rb b/spec/ruby/core/integer/shared/arithmetic_coerce.rb
index 4c0cbcb999..1260192df1 100644
--- a/spec/ruby/core/integer/shared/arithmetic_coerce.rb
+++ b/spec/ruby/core/integer/shared/arithmetic_coerce.rb
@@ -1,25 +1,5 @@
 require_relative '../fixtures/classes'
 
-describe :integer_arithmetic_coerce_rescue, shared: true do
-  it "rescues exception (StandardError and subclasses) raised in other#coerce and raises TypeError" do
-    b = mock("numeric with failed #coerce")
-    b.should_receive(:coerce).and_raise(IntegerSpecs::CoerceError)
-
-    # e.g. 1 + b
-    -> { 1.send(@method, b) }.should raise_error(TypeError, /MockObject can't be coerced into Integer/)
-  end
-
-  it "does not rescue Exception and StandardError siblings raised in other#coerce" do
-    [Exception, NoMemoryError].each do |exception|
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(exception)
-
-      # e.g. 1 + b
-      -> { 1.send(@method, b) }.should raise_error(exception)
-    end
-  end
-end
-
 describe :integer_arithmetic_coerce_not_rescue, shared: true do
   it "does not rescue exception raised in other#coerce" do
     b = mock("numeric with failed #coerce")
diff --git a/spec/ruby/core/integer/shared/integer_rounding.rb b/spec/ruby/core/integer/shared/integer_rounding.rb
index 3fb6e830ef..56d1819f84 100644
--- a/spec/ruby/core/integer/shared/integer_rounding.rb
+++ b/spec/ruby/core/integer/shared/integer_rounding.rb
@@ -11,19 +11,9 @@ describe :integer_rounding_positive_precision, shared: true do
     end
   end
 
-  ruby_version_is "2.4"..."2.5" do
-    it "returns itself as a float if passed a positive precision" do
-      [2, -4, 10**70, -10**100].each do |v|
-        v.send(@method, 42).should eql(v.to_f)
-      end
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns itself if passed a positive precision" do
-      [2, -4, 10**70, -10**100].each do |v|
-        v.send(@method, 42).should eql(v)
-      end
+  it "returns itself if passed a positive precision" do
+    [2, -4, 10**70, -10**100].each do |v|
+      v.send(@method, 42).should eql(v)
     end
   end
 end
diff --git a/spec/ruby/core/integer/sqrt_spec.rb b/spec/ruby/core/integer/sqrt_spec.rb
index e56da058a0..4149ca2cc9 100644
--- a/spec/ruby/core/integer/sqrt_spec.rb
+++ b/spec/ruby/core/integer/sqrt_spec.rb
@@ -1,33 +1,31 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Integer.sqrt" do
-    it "returns an integer" do
-      Integer.sqrt(10).should be_kind_of(Integer)
-    end
+describe "Integer.sqrt" do
+  it "returns an integer" do
+    Integer.sqrt(10).should be_kind_of(Integer)
+  end
 
-    it "returns the integer square root of the argument" do
-      Integer.sqrt(0).should == 0
-      Integer.sqrt(1).should == 1
-      Integer.sqrt(24).should == 4
-      Integer.sqrt(25).should == 5
-      Integer.sqrt(10**400).should == 10**200
-    end
+  it "returns the integer square root of the argument" do
+    Integer.sqrt(0).should == 0
+    Integer.sqrt(1).should == 1
+    Integer.sqrt(24).should == 4
+    Integer.sqrt(25).should == 5
+    Integer.sqrt(10**400).should == 10**200
+  end
 
-    it "raises a Math::DomainError if the argument is negative" do
-      -> { Integer.sqrt(-4) }.should raise_error(Math::DomainError)
-    end
+  it "raises a Math::DomainError if the argument is negative" do
+    -> { Integer.sqrt(-4) }.should raise_error(Math::DomainError)
+  end
 
-    it "accepts any argument that can be coerced to Integer" do
-      Integer.sqrt(10.0).should == 3
-    end
+  it "accepts any argument that can be coerced to Integer" do
+    Integer.sqrt(10.0).should == 3
+  end
 
-    it "converts the argument with #to_int" do
-      Integer.sqrt(mock_int(10)).should == 3
-    end
+  it "converts the argument with #to_int" do
+    Integer.sqrt(mock_int(10)).should == 3
+  end
 
-    it "raises a TypeError if the argument cannot be coerced to Integer" do
-      -> { Integer.sqrt("test") }.should raise_error(TypeError)
-    end
+  it "raises a TypeError if the argument cannot be coerced to Integer" do
+    -> { Integer.sqrt("test") }.should raise_error(TypeError)
   end
 end
diff --git a/spec/ruby/core/io/close_spec.rb b/spec/ruby/core/io/close_spec.rb
index 21bba32cd8..37c8ab5a12 100644
--- a/spec/ruby/core/io/close_spec.rb
+++ b/spec/ruby/core/io/close_spec.rb
@@ -44,22 +44,20 @@ describe "IO#close" do
     @io.close.should be_nil
   end
 
-  ruby_version_is '2.5' do
-    it 'raises an IOError with a clear message' do
-      read_io, write_io = IO.pipe
-      going_to_read = false
-      thread = Thread.new do
-        -> do
-          going_to_read = true
-          read_io.read
-        end.should raise_error(IOError, 'stream closed in another thread')
-      end
-
-      Thread.pass until going_to_read && thread.stop?
-      read_io.close
-      thread.join
-      write_io.close
+  it 'raises an IOError with a clear message' do
+    read_io, write_io = IO.pipe
+    going_to_read = false
+    thread = Thread.new do
+      -> do
+        going_to_read = true
+        read_io.read
+      end.should raise_error(IOError, 'stream closed in another thread')
     end
+
+    Thread.pass until going_to_read && thread.stop?
+    read_io.close
+    thread.join
+    write_io.close
   end
 end
 
diff --git a/spec/ruby/core/io/pread_spec.rb b/spec/ruby/core/io/pread_spec.rb
index bfe6472fef..43071d6a31 100644
--- a/spec/ruby/core/io/pread_spec.rb
+++ b/spec/ruby/core/io/pread_spec.rb
@@ -1,52 +1,50 @@
 # -*- encoding: utf-8 -*-
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  platform_is_not :windows do
-    describe "IO#pread" do
-      before :each do
-        @fname = tmp("io_pread.txt")
-        @contents = "1234567890"
-        touch(@fname) { |f| f.write @contents }
-        @file = File.open(@fname, "r+")
-      end
-
-      after :each do
-        @file.close
-        rm_r @fname
-      end
+platform_is_not :windows do
+  describe "IO#pread" do
+    before :each do
+      @fname = tmp("io_pread.txt")
+      @contents = "1234567890"
+      touch(@fname) { |f| f.write @contents }
+      @file = File.open(@fname, "r+")
+    end
 
-      it "accepts a length, and an offset" do
-        @file.pread(4, 0).should == "1234"
-        @file.pread(3, 4).should == "567"
-      end
+    after :each do
+      @file.close
+      rm_r @fname
+    end
 
-      it "accepts a length, an offset, and an output buffer" do
-        buffer = "foo"
-        @file.pread(3, 4, buffer)
-        buffer.should == "567"
-      end
+    it "accepts a length, and an offset" do
+      @file.pread(4, 0).should == "1234"
+      @file.pread(3, 4).should == "567"
+    end
 
-      it "does not advance the file pointer" do
-        @file.pread(4, 0).should == "1234"
-        @file.read.should == "1234567890"
-      end
+    it "accepts a length, an offset, and an output buffer" do
+      buffer = "foo"
+      @file.pread(3, 4, buffer)
+      buffer.should == "567"
+    end
 
-      it "raises EOFError if end-of-file is reached" do
-        -> { @file.pread(1, 10) }.should raise_error(EOFError)
-      end
+    it "does not advance the file pointer" do
+      @file.pread(4, 0).should == "1234"
+      @file.read.should == "1234567890"
+    end
 
-      it "raises IOError when file is not open in read mode" do
-        File.open(@fname, "w") do |file|
-          -> { file.pread(1, 1) }.should raise_error(IOError)
-        end
-      end
+    it "raises EOFError if end-of-file is reached" do
+      -> { @file.pread(1, 10) }.should raise_error(EOFError)
+    end
 
-      it "raises IOError when file is closed" do
-        file = File.open(@fname, "r+")
-        file.close
+    it "raises IOError when file is not open in read mode" do
+      File.open(@fname, "w") do |file|
         -> { file.pread(1, 1) }.should raise_error(IOError)
       end
     end
+
+    it "raises IOError when file is closed" do
+      file = File.open(@fname, "r+")
+      file.close
+      -> { file.pread(1, 1) }.should raise_error(IOError)
+    end
   end
 end
diff --git a/spec/ruby/core/io/pwrite_spec.rb b/spec/ruby/core/io/pwrite_spec.rb
index 929ed08698..fe29d1e1f6 100644
--- a/spec/ruby/core/io/pwrite_spec.rb
+++ b/spec/ruby/core/io/pwrite_spec.rb
@@ -1,45 +1,43 @@
 # -*- encoding: utf-8 -*-
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  platform_is_not :windows do
-    describe "IO#pwrite" do
-      before :each do
-        @fname = tmp("io_pwrite.txt")
-        @file = File.open(@fname, "w+")
-      end
-
-      after :each do
-        @file.close
-        rm_r @fname
-      end
+platform_is_not :windows do
+  describe "IO#pwrite" do
+    before :each do
+      @fname = tmp("io_pwrite.txt")
+      @file = File.open(@fname, "w+")
+    end
 
-      it "returns the number of bytes written" do
-        @file.pwrite("foo", 0).should == 3
-      end
+    after :each do
+      @file.close
+      rm_r @fname
+    end
 
-      it "accepts a string and an offset"  do
-        @file.pwrite("foo", 2)
-        @file.pread(3, 2).should == "foo"
-      end
+    it "returns the number of bytes written" do
+      @file.pwrite("foo", 0).should == 3
+    end
 
-      it "does not advance the pointer in the file" do
-        @file.pwrite("bar", 3)
-        @file.write("foo")
-        @file.pread(6, 0).should == "foobar"
-      end
+    it "accepts a string and an offset"  do
+      @file.pwrite("foo", 2)
+      @file.pread(3, 2).should == "foo"
+    end
 
-      it "raises IOError when file is not open in write mode" do
-        File.open(@fname, "r") do |file|
-          -> { file.pwrite("foo", 1) }.should raise_error(IOError)
-        end
-      end
+    it "does not advance the pointer in the file" do
+      @file.pwrite("bar", 3)
+      @file.write("foo")
+      @file.pread(6, 0).should == "foobar"
+    end
 
-      it "raises IOError when file is closed" do
-        file = File.open(@fname, "w+")
-        file.close
+    it "raises IOError when file is not open in write mode" do
+      File.open(@fname, "r") do |file|
         -> { file.pwrite("foo", 1) }.should raise_error(IOError)
       end
     end
+
+    it "raises IOError when file is closed" do
+      file = File.open(@fname, "w+")
+      file.close
+      -> { file.pwrite("foo", 1) }.should raise_error(IOError)
+    end
   end
 end
diff --git a/spec/ruby/core/io/write_spec.rb b/spec/ruby/core/io/write_spec.rb
index b28b582019..9c9b8b254b 100644
--- a/spec/ruby/core/io/write_spec.rb
+++ b/spec/ruby/core/io/write_spec.rb
@@ -126,14 +126,12 @@ end
 describe "IO#write" do
   it_behaves_like :io_write, :write
 
-  ruby_version_is "2.5" do
-    it "accepts multiple arguments" do
-      IO.pipe do |r, w|
-        w.write("foo", "bar")
-        w.close
+  it "accepts multiple arguments" do
+    IO.pipe do |r, w|
+      w.write("foo", "bar")
+      w.close
 
-        r.read.should == "foobar"
-      end
+      r.read.should == "foobar"
     end
   end
 end
diff --git a/spec/ruby/core/kernel/freeze_spec.rb b/spec/ruby/core/kernel/freeze_spec.rb
index 214b619f9f..e4a01b5df5 100644
--- a/spec/ruby/core/kernel/freeze_spec.rb
+++ b/spec/ruby/core/kernel/freeze_spec.rb
@@ -51,21 +51,19 @@ describe "Kernel#freeze" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe "on a Complex" do
-      it "has no effect since it is already frozen" do
-        c = Complex(1.3, 3.1)
-        c.frozen?.should be_true
-        c.freeze
-      end
+  describe "on a Complex" do
+    it "has no effect since it is already frozen" do
+      c = Complex(1.3, 3.1)
+      c.frozen?.should be_true
+      c.freeze
     end
+  end
 
-    describe "on a Rational" do
-      it "has no effect since it is already frozen" do
-        r = Rational(1, 3)
-        r.frozen?.should be_true
-        r.freeze
-      end
+  describe "on a Rational" do
+    it "has no effect since it is already frozen" do
+      r = Rational(1, 3)
+      r.frozen?.should be_true
+      r.freeze
     end
   end
 
diff --git a/spec/ruby/core/kernel/frozen_spec.rb b/spec/ruby/core/kernel/frozen_spec.rb
index 5887ed75ba..54edae15b1 100644
--- a/spec/ruby/core/kernel/frozen_spec.rb
+++ b/spec/ruby/core/kernel/frozen_spec.rb
@@ -50,29 +50,27 @@ describe "Kernel#frozen?" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe "on a Complex" do
-      it "returns true" do
-        c = Complex(1.3, 3.1)
-        c.frozen?.should be_true
-      end
+  describe "on a Complex" do
+    it "returns true" do
+      c = Complex(1.3, 3.1)
+      c.frozen?.should be_true
+    end
 
-      it "literal returns true" do
-        c = eval "1.3i"
-        c.frozen?.should be_true
-      end
+    it "literal returns true" do
+      c = eval "1.3i"
+      c.frozen?.should be_true
     end
+  end
 
-    describe "on a Rational" do
-      it "returns true" do
-        r = Rational(1, 3)
-        r.frozen?.should be_true
-      end
+  describe "on a Rational" do
+    it "returns true" do
+      r = Rational(1, 3)
+      r.frozen?.should be_true
+    end
 
-      it "literal returns true" do
-        r = eval "1/3r"
-        r.frozen?.should be_true
-      end
+    it "literal returns true" do
+      r = eval "1/3r"
+      r.frozen?.should be_true
     end
   end
 end
diff --git a/spec/ruby/core/kernel/pp_spec.rb b/spec/ruby/core/kernel/pp_spec.rb
index e19dc64caf..b5b1c98d38 100644
--- a/spec/ruby/core/kernel/pp_spec.rb
+++ b/spec/ruby/core/kernel/pp_spec.rb
@@ -1,11 +1,9 @@
 require_relative '../../spec_helper'
 
-ruby_version_is "2.5" do
-  describe "Kernel#pp" do
-    it "lazily loads the 'pp' library and delegates the call to that library" do
-      # Run in child process to ensure 'pp' hasn't been loaded yet.
-      output = ruby_exe("pp [1, 2, 3]")
-      output.should == "[1, 2, 3]\n"
-    end
+describe "Kernel#pp" do
+  it "lazily loads the 'pp' library and delegates the call to that library" do
+    # Run in child process to ensure 'pp' hasn't been loaded yet.
+    output = ruby_exe("pp [1, 2, 3]")
+    output.should == "[1, 2, 3]\n"
   end
 end
diff --git a/spec/ruby/core/kernel/shared/dup_clone.rb b/spec/ruby/core/kernel/shared/dup_clone.rb
index a52ccab359..968efd80f3 100644
--- a/spec/ruby/core/kernel/shared/dup_clone.rb
+++ b/spec/ruby/core/kernel/shared/dup_clone.rb
@@ -103,27 +103,13 @@ describe :kernel_dup_clone, shared: true do
     :my_symbol.send(@method).should == :my_symbol
   end
 
-  ruby_version_is ''...'2.5' do
-    it "raises a TypeError for Complex" do
-      c = Complex(1.3, 3.1)
-      -> { c.send(@method) }.should raise_error(TypeError)
-    end
-
-    it "raises a TypeError for Rational" do
-      r = Rational(1, 3)
-      -> { r.send(@method) }.should raise_error(TypeError)
-    end
+  it "returns self for Complex" do
+    c = Complex(1.3, 3.1)
+    c.send(@method).should equal c
   end
 
-  ruby_version_is '2.5' do
-    it "returns self for Complex" do
-      c = Complex(1.3, 3.1)
-      c.send(@method).should equal c
-    end
-
-    it "returns self for Rational" do
-      r = Rational(1, 3)
-      r.send(@method).should equal r
-    end
+  it "returns self for Rational" do
+    r = Rational(1, 3)
+    r.send(@method).should equal r
   end
 end
diff --git a/spec/ruby/core/kernel/shared/require.rb b/spec/ruby/core/kernel/shared/require.rb
index 52089f22fe..69977194e9 100644
--- a/spec/ruby/core/kernel/shared/require.rb
+++ b/spec/ruby/core/kernel/shared/require.rb
@@ -354,26 +354,13 @@ describe :kernel_require, shared: true do
           rm_r @dir, @symlink_to_dir
         end
 
-        ruby_version_is ""..."2.4.4" do
-          it "canonicalizes neither the entry in $LOAD_PATH nor the filename passed to #require" do
-            $LOAD_PATH.unshift(@symlink_to_dir)
-            @object.require("symfile").should be_true
-            loaded_feature = "#{@symlink_to_dir}/symfile.rb"
-            ScratchPad.recorded.should == [loaded_feature]
-            $".last.should == loaded_feature
-            $LOAD_PATH[0].should == @symlink_to_dir
-          end
-        end
-
-        ruby_version_is "2.4.4" do
-          it "canonicalizes the entry in $LOAD_PATH but not the filename passed to #require" do
-            $LOAD_PATH.unshift(@symlink_to_dir)
-            @object.require("symfile").should be_true
-            loaded_feature = "#{@dir}/symfile.rb"
-            ScratchPad.recorded.should == [loaded_feature]
-            $".last.should == loaded_feature
-            $LOAD_PATH[0].should == @symlink_to_dir
-          end
+        it "canonicalizes the entry in $LOAD_PATH but not the filename passed to #require" do
+          $LOAD_PATH.unshift(@symlink_to_dir)
+          @object.require("symfile").should be_true
+          loaded_feature = "#{@dir}/symfile.rb"
+          ScratchPad.recorded.should == [loaded_feature]
+          $".last.should == loaded_feature
+          $LOAD_PATH[0].should == @symlink_to_dir
         end
       end
     end
@@ -527,41 +514,25 @@ describe :kernel_require, shared: true do
       ScratchPad.recorded.should == []
     end
 
-    ruby_version_is ""..."2.5" do
-      it "complex, enumerator, rational, thread and unicode_normalize are already required" do
-        provided = %w[complex enumerator rational thread unicode_normalize]
-        features = ruby_exe("puts $LOADED_FEATURES", options: '--disable-gems')
-        provided.each { |feature|
-          features.should =~ /\b#{feature}\.(rb|so|jar)$/
-        }
+    it "complex, enumerator, rational and thread are already required" do
+      provided = %w[complex enumerator rational thread]
+      features = ruby_exe("puts $LOADED_FEATURES", options: '--disable-gems')
+      provided.each { |feature|
+        features.should =~ /\b#{feature}\.(rb|so|jar)$/
+      }
 
-        code = provided.map { |f| "puts require #{f.inspect}\n" }.join
-        required = ruby_exe(code, options: '--disable-gems')
-        required.should == "false\n" * provided.size
-      end
+      code = provided.map { |f| "puts require #{f.inspect}\n" }.join
+      required = ruby_exe(code, options: '--disable-gems')
+      required.should == "false\n" * provided.size
     end
 
-    ruby_version_is "2.5" do
-      it "complex, enumerator, rational and thread are already required" do
-        provided = %w[complex enumerator rational thread]
-        features = ruby_exe("puts $LOADED_FEATURES", options: '--disable-gems')
-        provided.each { |feature|
-          features.should =~ /\b#{feature}\.(rb|so|jar)$/
-        }
-
-        code = provided.map { |f| "puts require #{f.inspect}\n" }.join
-        required = ruby_exe(code, options: '--disable-gems')
-        required.should == "false\n" * provided.size
-      end
+    it "unicode_normalize is part of core and not $LOADED_FEATURES" do
+      features = ruby_exe("puts $LOADED_FEATURES", options: '--disable-gems')
+      features.lines.each { |feature|
+        feature.should_not include("unicode_normalize")
+      }
 
-      it "unicode_normalize is part of core and not $LOADED_FEATURES" do
-        features = ruby_exe("puts $LOADED_FEATURES", options: '--disable-gems')
-        features.lines.each { |feature|
-          feature.should_not include("unicode_normalize")
-        }
-
-        -> { @object.require("unicode_normalize") }.should raise_error(LoadError)
-      end
+      -> { @object.require("unicode_normalize") }.should raise_error(LoadError)
     end
   end
 
diff --git a/spec/ruby/core/kernel/shared/sprintf.rb b/spec/ruby/core/kernel/shared/sprintf.rb
index 1ad6f8a3cf..ca1e6bb2ed 100644
--- a/spec/ruby/core/kernel/shared/sprintf.rb
+++ b/spec/ruby/core/kernel/shared/sprintf.rb
@@ -345,18 +345,10 @@ describe :kernel_sprintf, shared: true do
     end
 
     describe "%" do
-      ruby_version_is ""..."2.5" do
-        it "alone displays the percent sign" do
-          @method.call("%").should == "%"
-        end
-      end
-
-      ruby_version_is "2.5" do
-        it "alone raises an ArgumentError" do
-          -> {
-            @method.call("%")
-          }.should raise_error(ArgumentError)
-        end
+      it "alone raises an ArgumentError" do
+        -> {
+          @method.call("%")
+        }.should raise_error(ArgumentError)
       end
 
       it "is escaped by %" do
@@ -876,22 +868,20 @@ describe :kernel_sprintf, shared: true do
       }.should raise_error(KeyError)
     end
 
-    ruby_version_is "2.5" do
-      it "sets the Hash as the receiver of KeyError" do
-        -> {
-          @method.call("%<foo>s", @object)
-        }.should raise_error(KeyError) { |err|
-          err.receiver.should equal(@object)
-        }
-      end
+    it "sets the Hash as the receiver of KeyError" do
+      -> {
+        @method.call("%<foo>s", @object)
+      }.should raise_error(KeyError) { |err|
+        err.receiver.should equal(@object)
+      }
+    end
 
-      it "sets the unmatched key as the key of KeyError" do
-        -> {
-          @method.call("%<foo>s", @object)
-        }.should raise_error(KeyError) { |err|
-          err.key.to_s.should == 'foo'
-        }
-      end
+    it "sets the unmatched key as the key of KeyError" do
+      -> {
+        @method.call("%<foo>s", @object)
+      }.should raise_error(KeyError) { |err|
+        err.key.to_s.should == 'foo'
+      }
     end
   end
 end
diff --git a/spec/ruby/core/kernel/warn_spec.rb b/spec/ruby/core/kernel/warn_spec.rb
index 774f4378ad..84cfa78672 100644
--- a/spec/ruby/core/kernel/warn_spec.rb
+++ b/spec/ruby/core/kernel/warn_spec.rb
@@ -87,71 +87,69 @@ describe "Kernel#warn" do
     }.should output(nil, "to_s called\n")
   end
 
-  ruby_version_is "2.5" do
-    describe ":uplevel keyword argument" do
-      before :each do
-        $VERBOSE = true
-      end
-
-      it "prepends a message with specified line from the backtrace" do
-        w = KernelSpecs::WarnInNestedCall.new
-
-        -> { w.f4("foo", 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: foo|)
-        -> { w.f4("foo", 1) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f1_call_lineno}: warning: foo|)
-        -> { w.f4("foo", 2) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f2_call_lineno}: warning: foo|)
-        -> { w.f4("foo", 3) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f3_call_lineno}: warning: foo|)
-      end
-
-      it "converts first arg using to_s" do
-        w = KernelSpecs::WarnInNestedCall.new
-
-        -> { w.f4(false, 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: false|)
-        -> { w.f4(nil, 1) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f1_call_lineno}: warning: |)
-        obj = mock("obj")
-        obj.should_receive(:to_s).and_return("to_s called")
-        -> { w.f4(obj, 2) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f2_call_lineno}: warning: to_s called|)
-      end
-
-      it "does not prepend caller information if the uplevel argument is too large" do
-        w = KernelSpecs::WarnInNestedCall.new
-        -> { w.f4("foo", 100) }.should output(nil, "warning: foo\n")
-      end
-
-      it "prepends even if a message is empty or nil" do
-        w = KernelSpecs::WarnInNestedCall.new
-
-        -> { w.f4("", 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: \n$|)
-        -> { w.f4(nil, 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: \n$|)
-      end
-
-      it "converts value to Integer" do
-        w = KernelSpecs::WarnInNestedCall.new
-
-        -> { w.f4(0.1) }.should output(nil, %r|classes.rb:#{w.warn_call_lineno}:|)
-        -> { w.f4(Rational(1, 2)) }.should output(nil, %r|classes.rb:#{w.warn_call_lineno}:|)
-      end
-
-      it "raises ArgumentError if passed negative value" do
-        -> { warn "", uplevel: -2 }.should raise_error(ArgumentError)
-        -> { warn "", uplevel: -100 }.should raise_error(ArgumentError)
-      end
-
-      it "raises ArgumentError if passed -1" do
-        -> { warn "", uplevel: -1 }.should raise_error(ArgumentError)
-      end
-
-      it "raises TypeError if passed not Integer" do
-        -> { warn "", uplevel: "" }.should raise_error(TypeError)
-        -> { warn "", uplevel: [] }.should raise_error(TypeError)
-        -> { warn "", uplevel: {} }.should raise_error(TypeError)
-        -> { warn "", uplevel: Object.new }.should raise_error(TypeError)
-      end
+  describe ":uplevel keyword argument" do
+    before :each do
+      $VERBOSE = true
+    end
+
+    it "prepends a message with specified line from the backtrace" do
+      w = KernelSpecs::WarnInNestedCall.new
+
+      -> { w.f4("foo", 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: foo|)
+      -> { w.f4("foo", 1) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f1_call_lineno}: warning: foo|)
+      -> { w.f4("foo", 2) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f2_call_lineno}: warning: foo|)
+      -> { w.f4("foo", 3) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f3_call_lineno}: warning: foo|)
     end
 
-    it "treats empty hash as no keyword argument" do
-      h = {}
-      -> { warn(**h) }.should_not complain(verbose: true)
-      -> { warn('foo', **h) }.should complain("foo\n")
+    it "converts first arg using to_s" do
+      w = KernelSpecs::WarnInNestedCall.new
+
+      -> { w.f4(false, 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: false|)
+      -> { w.f4(nil, 1) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f1_call_lineno}: warning: |)
+      obj = mock("obj")
+      obj.should_receive(:to_s).and_return("to_s called")
+      -> { w.f4(obj, 2) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.f2_call_lineno}: warning: to_s called|)
     end
+
+    it "does not prepend caller information if the uplevel argument is too large" do
+      w = KernelSpecs::WarnInNestedCall.new
+      -> { w.f4("foo", 100) }.should output(nil, "warning: foo\n")
+    end
+
+    it "prepends even if a message is empty or nil" do
+      w = KernelSpecs::WarnInNestedCall.new
+
+      -> { w.f4("", 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: \n$|)
+      -> { w.f4(nil, 0) }.should output(nil, %r|core/kernel/fixtures/classes.rb:#{w.warn_call_lineno}: warning: \n$|)
+    end
+
+    it "converts value to Integer" do
+      w = KernelSpecs::WarnInNestedCall.new
+
+      -> { w.f4(0.1) }.should output(nil, %r|classes.rb:#{w.warn_call_lineno}:|)
+      -> { w.f4(Rational(1, 2)) }.should output(nil, %r|classes.rb:#{w.warn_call_lineno}:|)
+    end
+
+    it "raises ArgumentError if passed negative value" do
+      -> { warn "", uplevel: -2 }.should raise_error(ArgumentError)
+      -> { warn "", uplevel: -100 }.should raise_error(ArgumentError)
+    end
+
+    it "raises ArgumentError if passed -1" do
+      -> { warn "", uplevel: -1 }.should raise_error(ArgumentError)
+    end
+
+    it "raises TypeError if passed not Integer" do
+      -> { warn "", uplevel: "" }.should raise_error(TypeError)
+      -> { warn "", uplevel: [] }.should raise_error(TypeError)
+      -> { warn "", uplevel: {} }.should raise_error(TypeError)
+      -> { warn "", uplevel: Object.new }.should raise_error(TypeError)
+    end
+  end
+
+  it "treats empty hash as no keyword argument" do
+    h = {}
+    -> { warn(**h) }.should_not complain(verbose: true)
+    -> { warn('foo', **h) }.should complain("foo\n")
   end
 end
diff --git a/spec/ruby/core/kernel/yield_self_spec.rb b/spec/ruby/core/kernel/yield_self_spec.rb
index affedae144..e311dcee47 100644
--- a/spec/ruby/core/kernel/yield_self_spec.rb
+++ b/spec/ruby/core/kernel/yield_self_spec.rb
@@ -1,8 +1,6 @@
 require_relative '../../spec_helper'
 require_relative 'shared/then'
 
-ruby_version_is "2.5" do
-  describe "Kernel#yield_self" do
-    it_behaves_like :kernel_then, :yield_self
-  end
+describe "Kernel#yield_self" do
+  it_behaves_like :kernel_then, :yield_self
 end
diff --git a/spec/ruby/core/method/case_compare_spec.rb b/spec/ruby/core/method/case_compare_spec.rb
index 17785b5c1d..a78953e8ad 100644
--- a/spec/ruby/core/method/case_compare_spec.rb
+++ b/spec/ruby/core/method/case_compare_spec.rb
@@ -2,8 +2,6 @@ require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 require_relative 'shared/call'
 
-ruby_version_is "2.5" do
-  describe "Method#===" do
-    it_behaves_like :method_call, :===
-  end
+describe "Method#===" do
+  it_behaves_like :method_call, :===
 end
diff --git a/spec/ruby/core/module/alias_method_spec.rb b/spec/ruby/core/module/alias_method_spec.rb
index b47ddc22d4..742e289a3f 100644
--- a/spec/ruby/core/module/alias_method_spec.rb
+++ b/spec/ruby/core/module/alias_method_spec.rb
@@ -81,15 +81,8 @@ describe "Module#alias_method" do
     -> { @class.make_alias mock('x'), :public_one }.should raise_error(TypeError)
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      -> { @class.alias_method :ichi, :public_one }.should raise_error(NoMethodError)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:alias_method, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:alias_method, false)
   end
 
   it "returns self" do
diff --git a/spec/ruby/core/module/attr_accessor_spec.rb b/spec/ruby/core/module/attr_accessor_spec.rb
index ce95ccd487..6a749341be 100644
--- a/spec/ruby/core/module/attr_accessor_spec.rb
+++ b/spec/ruby/core/module/attr_accessor_spec.rb
@@ -63,15 +63,8 @@ describe "Module#attr_accessor" do
     -> { c.new.foo=1 }.should raise_error(NoMethodError)
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:attr_accessor, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:attr_accessor, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:attr_accessor, false)
   end
 
   describe "on immediates" do
diff --git a/spec/ruby/core/module/attr_reader_spec.rb b/spec/ruby/core/module/attr_reader_spec.rb
index 082bc03b60..238e3db9ea 100644
--- a/spec/ruby/core/module/attr_reader_spec.rb
+++ b/spec/ruby/core/module/attr_reader_spec.rb
@@ -58,14 +58,7 @@ describe "Module#attr_reader" do
     -> { c.new.foo }.should raise_error(NoMethodError)
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:attr_reader, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:attr_reader, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:attr_reader, false)
   end
 end
diff --git a/spec/ruby/core/module/attr_spec.rb b/spec/ruby/core/module/attr_spec.rb
index 20316a3d39..8b91e77658 100644
--- a/spec/ruby/core/module/attr_spec.rb
+++ b/spec/ruby/core/module/attr_spec.rb
@@ -142,14 +142,7 @@ describe "Module#attr" do
     }.should complain(/boolean argument is obsoleted/, verbose: true)
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:attr, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:attr, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:attr, false)
   end
 end
diff --git a/spec/ruby/core/module/attr_writer_spec.rb b/spec/ruby/core/module/attr_writer_spec.rb
index 3b110cecf7..e4b193a9d8 100644
--- a/spec/ruby/core/module/attr_writer_spec.rb
+++ b/spec/ruby/core/module/attr_writer_spec.rb
@@ -58,14 +58,7 @@ describe "Module#attr_writer" do
     -> { c.new.foo=1 }.should raise_error(NoMethodError)
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:attr_writer, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:attr_writer, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:attr_writer, false)
   end
 end
diff --git a/spec/ruby/core/module/define_method_spec.rb b/spec/ruby/core/module/define_method_spec.rb
index be61c62659..49472c18e1 100644
--- a/spec/ruby/core/module/define_method_spec.rb
+++ b/spec/ruby/core/module/define_method_spec.rb
@@ -355,15 +355,8 @@ describe "Module#define_method" do
     klass.new.string_test.should == "string_test result"
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:define_method)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:define_method)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:define_method)
   end
 
   it "returns its symbol" do
diff --git a/spec/ruby/core/module/refine_spec.rb b/spec/ruby/core/module/refine_spec.rb
index 81dd492362..6df4fa4719 100644
--- a/spec/ruby/core/module/refine_spec.rb
+++ b/spec/ruby/core/module/refine_spec.rb
@@ -393,44 +393,22 @@ describe "Module#refine" do
       end
     end
 
-    ruby_version_is "" ... "2.5" do
-      it "is not honored by string interpolation" do
-        refinement = Module.new do
-          refine Integer do
-            def to_s
-              "foo"
-            end
+    it "is honored by string interpolation" do
+      refinement = Module.new do
+        refine Integer do
+          def to_s
+            "foo"
           end
         end
-
-        result = nil
-        Module.new do
-          using refinement
-          result = "#{1}"
-        end
-
-        result.should == "1"
       end
-    end
-
-    ruby_version_is "2.5" do
-      it "is honored by string interpolation" do
-        refinement = Module.new do
-          refine Integer do
-            def to_s
-              "foo"
-            end
-          end
-        end
-
-        result = nil
-        Module.new do
-          using refinement
-          result = "#{1}"
-        end
 
-        result.should == "foo"
+      result = nil
+      Module.new do
+        using refinement
+        result = "#{1}"
       end
+
+      result.should == "foo"
     end
 
     it "is honored by Kernel#binding" do
diff --git a/spec/ruby/core/module/remove_method_spec.rb b/spec/ruby/core/module/remove_method_spec.rb
index 0765c902b0..b6ae02078f 100644
--- a/spec/ruby/core/module/remove_method_spec.rb
+++ b/spec/ruby/core/module/remove_method_spec.rb
@@ -20,15 +20,8 @@ describe "Module#remove_method" do
     @module = Module.new { def method_to_remove; end }
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:remove_method, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:remove_method, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:remove_method, false)
   end
 
   it "removes the method from a class" do
diff --git a/spec/ruby/core/module/undef_method_spec.rb b/spec/ruby/core/module/undef_method_spec.rb
index 4eeaaef3a8..c2ad200536 100644
--- a/spec/ruby/core/module/undef_method_spec.rb
+++ b/spec/ruby/core/module/undef_method_spec.rb
@@ -18,15 +18,8 @@ describe "Module#undef_method" do
     @module = Module.new { def method_to_undef; end }
   end
 
-  ruby_version_is ''...'2.5' do
-    it "is a private method" do
-      Module.should have_private_instance_method(:undef_method, false)
-    end
-  end
-  ruby_version_is '2.5' do
-    it "is a public method" do
-      Module.should have_public_instance_method(:undef_method, false)
-    end
+  it "is a public method" do
+    Module.should have_public_instance_method(:undef_method, false)
   end
 
   it "requires multiple arguments" do
diff --git a/spec/ruby/core/numeric/shared/step.rb b/spec/ruby/core/numeric/shared/step.rb
index 364d4769ad..fac79b3e63 100644
--- a/spec/ruby/core/numeric/shared/step.rb
+++ b/spec/ruby/core/numeric/shared/step.rb
@@ -224,33 +224,25 @@ describe :numeric_step, :shared => true do
   end
 
   describe "when step is a String" do
-    error = nil
-    ruby_version_is "2.4"..."2.5" do
-      error = TypeError
-    end
-    ruby_version_is "2.5" do
-      error = ArgumentError
-    end
-
     describe "with self and stop as Fixnums" do
-      it "raises an #{error} when step is a numeric representation" do
-        -> { @step.call(1, 5, "1") {} }.should raise_error(error)
-        -> { @step.call(1, 5, "0.1") {} }.should raise_error(error)
-        -> { @step.call(1, 5, "1/3") {} }.should raise_error(error)
+      it "raises an ArgumentError when step is a numeric representation" do
+        -> { @step.call(1, 5, "1") {} }.should raise_error(ArgumentError)
+        -> { @step.call(1, 5, "0.1") {} }.should raise_error(ArgumentError)
+        -> { @step.call(1, 5, "1/3") {} }.should raise_error(ArgumentError)
       end
-      it "raises an #{error} with step as an alphanumeric string" do
-        -> { @step.call(1, 5, "foo") {} }.should raise_error(error)
+      it "raises an ArgumentError with step as an alphanumeric string" do
+        -> { @step.call(1, 5, "foo") {} }.should raise_error(ArgumentError)
       end
     end
 
     describe "with self and stop as Floats" do
-      it "raises an #{error} when step is a numeric representation" do
-        -> { @step.call(1.1, 5.1, "1") {} }.should raise_error(error)
-        -> { @step.call(1.1, 5.1, "0.1") {} }.should raise_error(error)
-        -> { @step.call(1.1, 5.1, "1/3") {} }.should raise_error(error)
+      it "raises an ArgumentError when step is a numeric representation" do
+        -> { @step.call(1.1, 5.1, "1") {} }.should raise_error(ArgumentError)
+        -> { @step.call(1.1, 5.1, "0.1") {} }.should raise_error(ArgumentError)
+        -> { @step.call(1.1, 5.1, "1/3") {} }.should raise_error(ArgumentError)
       end
-      it "raises an #{error} with step as an alphanumeric string" do
-        -> { @step.call(1.1, 5.1, "foo") {} }.should raise_error(error)
+      it "raises an ArgumentError with step as an alphanumeric string" do
+        -> { @step.call(1.1, 5.1, "foo") {} }.should raise_error(ArgumentError)
       end
     end
   end
@@ -302,33 +294,25 @@ describe :numeric_step, :shared => true do
     describe "returned Enumerator" do
       describe "size" do
         describe "when step is a String" do
-          error = nil
-          ruby_version_is "2.4"..."2.5" do
-            error = TypeError
-          end
-          ruby_version_is "2.5" do
-            error = ArgumentError
-          end
-
           describe "with self and stop as Fixnums" do
-            it "raises an #{error} when step is a numeric representation" do
-              -> { @step.call(1, 5, "1").size }.should raise_error(error)
-              -> { @step.call(1, 5, "0.1").size }.should raise_error(error)
-              -> { @step.call(1, 5, "1/3").size }.should raise_error(error)
+            it "raises an ArgumentError when step is a numeric representation" do
+              -> { @step.call(1, 5, "1").size }.should raise_error(ArgumentError)
+              -> { @step.call(1, 5, "0.1").size }.should raise_error(ArgumentError)
+              -> { @step.call(1, 5, "1/3").size }.should raise_error(ArgumentError)
             end
-            it "raises an #{error} with step as an alphanumeric string" do
-              -> { @step.call(1, 5, "foo").size }.should raise_error(error)
+            it "raises an ArgumentError with step as an alphanumeric string" do
+              -> { @step.call(1, 5, "foo").size }.should raise_error(ArgumentError)
             end
           end
 
           describe "with self and stop as Floats" do
-            it "raises an #{error} when step is a numeric representation" do
-              -> { @step.call(1.1, 5.1, "1").size }.should raise_error(error)
-              -> { @step.call(1.1, 5.1, "0.1").size }.should raise_error(error)
-              -> { @step.call(1.1, 5.1, "1/3").size }.should raise_error(error)
+            it "raises an ArgumentError when step is a numeric representation" do
+              -> { @step.call(1.1, 5.1, "1").size }.should raise_error(ArgumentError)
+              -> { @step.call(1.1, 5.1, "0.1").size }.should raise_error(ArgumentError)
+              -> { @step.call(1.1, 5.1, "1/3").size }.should raise_error(ArgumentError)
             end
-            it "raises an #{error} with step as an alphanumeric string" do
-              -> { @step.call(1.1, 5.1, "foo").size }.should raise_error(error)
+            it "raises an ArgumentError with step as an alphanumeric string" do
+              -> { @step.call(1.1, 5.1, "foo").size }.should raise_error(ArgumentError)
             end
           end
         end
diff --git a/spec/ruby/core/process/last_status_spec.rb b/spec/ruby/core/process/last_status_spec.rb
index 3898dd6b95..2372f2aae3 100644
--- a/spec/ruby/core/process/last_status_spec.rb
+++ b/spec/ruby/core/process/last_status_spec.rb
@@ -1,20 +1,18 @@
 require_relative '../../spec_helper'
 
-ruby_version_is '2.5' do
-  describe 'Process#last_status' do
-    it 'returns the status of the last executed child process in the current thread' do
-      pid = Process.wait Process.spawn("exit 0")
-      Process.last_status.pid.should == pid
-    end
+describe 'Process#last_status' do
+  it 'returns the status of the last executed child process in the current thread' do
+    pid = Process.wait Process.spawn("exit 0")
+    Process.last_status.pid.should == pid
+  end
 
-    it 'returns nil if no child process has been ever executed in the current thread' do
-      Thread.new do
-        Process.last_status.should == nil
-      end.join
-    end
+  it 'returns nil if no child process has been ever executed in the current thread' do
+    Thread.new do
+      Process.last_status.should == nil
+    end.join
+  end
 
-    it 'raises an ArgumentError if any arguments are provided' do
-      -> { Process.last_status(1) }.should raise_error(ArgumentError)
-    end
+  it 'raises an ArgumentError if any arguments are provided' do
+    -> { Process.last_status(1) }.should raise_error(ArgumentError)
   end
 end
diff --git a/spec/ruby/core/process/times_spec.rb b/spec/ruby/core/process/times_spec.rb
index 57595c321a..b47189a7e7 100644
--- a/spec/ruby/core/process/times_spec.rb
+++ b/spec/ruby/core/process/times_spec.rb
@@ -13,25 +13,23 @@ describe "Process.times" do
     Process.times.utime.should > user
   end
 
-  ruby_version_is "2.5" do
-    platform_is_not :windows do
-      it "uses getrusage when available to improve precision beyond milliseconds" do
-        max = 10_000
-        has_getrusage = max.times.find do
-          time = Process.clock_gettime(:GETRUSAGE_BASED_CLOCK_PROCESS_CPUTIME_ID)
-          ('%.6f' % time).end_with?('000')
-        end
-        unless has_getrusage
-          skip "getrusage is not supported on this environment"
-        end
-
-        found = (max * 100).times.find do
-          time = Process.times.utime
-          ('%.6f' % time).end_with?('000')
-        end
+  platform_is_not :windows do
+    it "uses getrusage when available to improve precision beyond milliseconds" do
+      max = 10_000
+      has_getrusage = max.times.find do
+        time = Process.clock_gettime(:GETRUSAGE_BASED_CLOCK_PROCESS_CPUTIME_ID)
+        ('%.6f' % time).end_with?('000')
+      end
+      unless has_getrusage
+        skip "getrusage is not supported on this environment"
+      end
 
-        found.should_not == nil
+      found = (max * 100).times.find do
+        time = Process.times.utime
+        ('%.6f' % time).end_with?('000')
       end
+
+      found.should_not == nil
     end
   end
 end
diff --git a/spec/ruby/core/random/raw_seed_spec.rb b/spec/ruby/core/random/raw_seed_spec.rb
index c1a1eb1f42..0e40ed0796 100644
--- a/spec/ruby/core/random/raw_seed_spec.rb
+++ b/spec/ruby/core/random/raw_seed_spec.rb
@@ -1,9 +1,6 @@
-# -*- encoding: binary -*-
 require_relative '../../spec_helper'
 require_relative 'shared/urandom'
 
-ruby_version_is "2.5" do
-  describe "Random.urandom" do
-    it_behaves_like :random_urandom, :urandom
-  end
+describe "Random.urandom" do
+  it_behaves_like :random_urandom, :urandom
 end
diff --git a/spec/ruby/core/random/urandom_spec.rb b/spec/ruby/core/random/urandom_spec.rb
deleted file mode 100644
index e27f83cdcd..0000000000
--- a/spec/ruby/core/random/urandom_spec.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-# -*- encoding: binary -*-
-require_relative '../../spec_helper'
-require_relative 'shared/urandom'
-
-ruby_version_is ""..."2.5" do
-  describe "Random.raw_seed" do
-    it_behaves_like :random_urandom, :raw_seed
-  end
-end
diff --git a/spec/ruby/core/range/new_spec.rb b/spec/ruby/core/range/new_spec.rb
index 9ed2b65d5a..be10ff244e 100644
--- a/spec/ruby/core/range/new_spec.rb
+++ b/spec/ruby/core/range/new_spec.rb
@@ -33,14 +33,12 @@ describe "Range.new" do
     -> { Range.new(a, b) }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is "2.5" do
-    it "does not rescue exception raised in #<=> when compares the given start and end" do
-      b = mock('a')
-      a = mock('b')
-      a.should_receive(:<=>).with(b).and_raise(RangeSpecs::ComparisonError)
+  it "does not rescue exception raised in #<=> when compares the given start and end" do
+    b = mock('a')
+    a = mock('b')
+    a.should_receive(:<=>).with(b).and_raise(RangeSpecs::ComparisonError)
 
-      -> { Range.new(a, b) }.should raise_error(RangeSpecs::ComparisonError)
-    end
+    -> { Range.new(a, b) }.should raise_error(RangeSpecs::ComparisonError)
   end
 
   describe "beginless/endless range" do
diff --git a/spec/ruby/core/string/casecmp_spec.rb b/spec/ruby/core/string/casecmp_spec.rb
index 01b22e8f13..986fbc8718 100644
--- a/spec/ruby/core/string/casecmp_spec.rb
+++ b/spec/ruby/core/string/casecmp_spec.rb
@@ -25,16 +25,8 @@ describe "String#casecmp independent of case" do
     "abc".casecmp(other).should == 0
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises a TypeError if other can't be converted to a string" do
-      -> { "abc".casecmp(mock('abc')) }.should raise_error(TypeError)
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns nil if other can't be converted to a string" do
-      "abc".casecmp(mock('abc')).should be_nil
-    end
+  it "returns nil if other can't be converted to a string" do
+    "abc".casecmp(mock('abc')).should be_nil
   end
 
   it "returns nil if incompatible encodings" do
@@ -196,15 +188,7 @@ describe 'String#casecmp? independent of case' do
     "ß".casecmp?("ss").should be_true
   end
 
-  ruby_version_is "2.4"..."2.5" do
-    it "raises a TypeError if other can't be converted to a string" do
-      -> { "abc".casecmp?(mock('abc')) }.should raise_error(TypeError)
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns nil if other can't be converted to a string" do
-      "abc".casecmp?(mock('abc')).should be_nil
-    end
+  it "returns nil if other can't be converted to a string" do
+    "abc".casecmp?(mock('abc')).should be_nil
   end
 end
diff --git a/spec/ruby/core/string/delete_prefix_spec.rb b/spec/ruby/core/string/delete_prefix_spec.rb
index 3332ca9d08..fb00d808b2 100644
--- a/spec/ruby/core/string/delete_prefix_spec.rb
+++ b/spec/ruby/core/string/delete_prefix_spec.rb
@@ -2,82 +2,80 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 
-ruby_version_is '2.5' do
-  describe "String#delete_prefix" do
-    it "returns a copy of the string, with the given prefix removed" do
-      'hello'.delete_prefix('hell').should == 'o'
-      'hello'.delete_prefix('hello').should == ''
-    end
+describe "String#delete_prefix" do
+  it "returns a copy of the string, with the given prefix removed" do
+    'hello'.delete_prefix('hell').should == 'o'
+    'hello'.delete_prefix('hello').should == ''
+  end
 
-    it "returns a copy of the string, when the prefix isn't found" do
-      s = 'hello'
-      r = s.delete_prefix('hello!')
-      r.should_not equal s
-      r.should == s
-      r = s.delete_prefix('ell')
-      r.should_not equal s
-      r.should == s
-      r = s.delete_prefix('')
-      r.should_not equal s
-      r.should == s
-    end
+  it "returns a copy of the string, when the prefix isn't found" do
+    s = 'hello'
+    r = s.delete_prefix('hello!')
+    r.should_not equal s
+    r.should == s
+    r = s.delete_prefix('ell')
+    r.should_not equal s
+    r.should == s
+    r = s.delete_prefix('')
+    r.should_not equal s
+    r.should == s
+  end
 
-    ruby_version_is ''...'2.7' do
-      it "taints resulting strings when other is tainted" do
-        'hello'.taint.delete_prefix('hell').tainted?.should == true
-        'hello'.taint.delete_prefix('').tainted?.should == true
-      end
+  ruby_version_is ''...'2.7' do
+    it "taints resulting strings when other is tainted" do
+      'hello'.taint.delete_prefix('hell').tainted?.should == true
+      'hello'.taint.delete_prefix('').tainted?.should == true
     end
+  end
 
-    it "doesn't set $~" do
-      $~ = nil
+  it "doesn't set $~" do
+    $~ = nil
 
-      'hello'.delete_prefix('hell')
-      $~.should == nil
-    end
+    'hello'.delete_prefix('hell')
+    $~.should == nil
+  end
 
-    it "calls to_str on its argument" do
-      o = mock('x')
-      o.should_receive(:to_str).and_return 'hell'
-      'hello'.delete_prefix(o).should == 'o'
-    end
+  it "calls to_str on its argument" do
+    o = mock('x')
+    o.should_receive(:to_str).and_return 'hell'
+    'hello'.delete_prefix(o).should == 'o'
+  end
 
-    it "returns a subclass instance when called on a subclass instance" do
-      s = StringSpecs::MyString.new('hello')
-      s.delete_prefix('hell').should be_an_instance_of(StringSpecs::MyString)
-    end
+  it "returns a subclass instance when called on a subclass instance" do
+    s = StringSpecs::MyString.new('hello')
+    s.delete_prefix('hell').should be_an_instance_of(StringSpecs::MyString)
   end
+end
 
-  describe "String#delete_prefix!" do
-    it "removes the found prefix" do
-      s = 'hello'
-      s.delete_prefix!('hell').should equal(s)
-      s.should == 'o'
-    end
+describe "String#delete_prefix!" do
+  it "removes the found prefix" do
+    s = 'hello'
+    s.delete_prefix!('hell').should equal(s)
+    s.should == 'o'
+  end
 
-    it "returns nil if no change is made" do
-      s = 'hello'
-      s.delete_prefix!('ell').should == nil
-      s.delete_prefix!('').should == nil
-    end
+  it "returns nil if no change is made" do
+    s = 'hello'
+    s.delete_prefix!('ell').should == nil
+    s.delete_prefix!('').should == nil
+  end
 
-    it "doesn't set $~" do
-      $~ = nil
+  it "doesn't set $~" do
+    $~ = nil
 
-      'hello'.delete_prefix!('hell')
-      $~.should == nil
-    end
+    'hello'.delete_prefix!('hell')
+    $~.should == nil
+  end
 
-    it "calls to_str on its argument" do
-      o = mock('x')
-      o.should_receive(:to_str).and_return 'hell'
-      'hello'.delete_prefix!(o).should == 'o'
-    end
+  it "calls to_str on its argument" do
+    o = mock('x')
+    o.should_receive(:to_str).and_return 'hell'
+    'hello'.delete_prefix!(o).should == 'o'
+  end
 
-    it "raises a FrozenError when self is frozen" do
-      -> { 'hello'.freeze.delete_prefix!('hell') }.should raise_error(FrozenError)
-      -> { 'hello'.freeze.delete_prefix!('') }.should raise_error(FrozenError)
-      -> { ''.freeze.delete_prefix!('') }.should raise_error(FrozenError)
-    end
+  it "raises a FrozenError when self is frozen" do
+    -> { 'hello'.freeze.delete_prefix!('hell') }.should raise_error(FrozenError)
+    -> { 'hello'.freeze.delete_prefix!('') }.should raise_error(FrozenError)
+    -> { ''.freeze.delete_prefix!('') }.should raise_error(FrozenError)
   end
 end
diff --git a/spec/ruby/core/string/delete_suffix_spec.rb b/spec/ruby/core/string/delete_suffix_spec.rb
index 4bc0549c88..d5b6880193 100644
--- a/spec/ruby/core/string/delete_suffix_spec.rb
+++ b/spec/ruby/core/string/delete_suffix_spec.rb
@@ -2,82 +2,80 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 
-ruby_version_is '2.5' do
-  describe "String#delete_suffix" do
-    it "returns a copy of the string, with the given suffix removed" do
-      'hello'.delete_suffix('ello').should == 'h'
-      'hello'.delete_suffix('hello').should == ''
-    end
+describe "String#delete_suffix" do
+  it "returns a copy of the string, with the given suffix removed" do
+    'hello'.delete_suffix('ello').should == 'h'
+    'hello'.delete_suffix('hello').should == ''
+  end
 
-    it "returns a copy of the string, when the suffix isn't found" do
-      s = 'hello'
-      r = s.delete_suffix('!hello')
-      r.should_not equal s
-      r.should == s
-      r = s.delete_suffix('ell')
-      r.should_not equal s
-      r.should == s
-      r = s.delete_suffix('')
-      r.should_not equal s
-      r.should == s
-    end
+  it "returns a copy of the string, when the suffix isn't found" do
+    s = 'hello'
+    r = s.delete_suffix('!hello')
+    r.should_not equal s
+    r.should == s
+    r = s.delete_suffix('ell')
+    r.should_not equal s
+    r.should == s
+    r = s.delete_suffix('')
+    r.should_not equal s
+    r.should == s
+  end
 
-    ruby_version_is ''...'2.7' do
-      it "taints resulting strings when other is tainted" do
-        'hello'.taint.delete_suffix('ello').tainted?.should == true
-        'hello'.taint.delete_suffix('').tainted?.should == true
-      end
+  ruby_version_is ''...'2.7' do
+    it "taints resulting strings when other is tainted" do
+      'hello'.taint.delete_suffix('ello').tainted?.should == true
+      'hello'.taint.delete_suffix('').tainted?.should == true
     end
+  end
 
-    it "doesn't set $~" do
-      $~ = nil
+  it "doesn't set $~" do
+    $~ = nil
 
-      'hello'.delete_suffix('ello')
-      $~.should == nil
-    end
+    'hello'.delete_suffix('ello')
+    $~.should == nil
+  end
 
-    it "calls to_str on its argument" do
-      o = mock('x')
-      o.should_receive(:to_str).and_return 'ello'
-      'hello'.delete_suffix(o).should == 'h'
-    end
+  it "calls to_str on its argument" do
+    o = mock('x')
+    o.should_receive(:to_str).and_return 'ello'
+    'hello'.delete_suffix(o).should == 'h'
+  end
 
-    it "returns a subclass instance when called on a subclass instance" do
-      s = StringSpecs::MyString.new('hello')
-      s.delete_suffix('ello').should be_an_instance_of(StringSpecs::MyString)
-    end
+  it "returns a subclass instance when called on a subclass instance" do
+    s = StringSpecs::MyString.new('hello')
+    s.delete_suffix('ello').should be_an_instance_of(StringSpecs::MyString)
   end
+end
 
-  describe "String#delete_suffix!" do
-    it "removes the found prefix" do
-      s = 'hello'
-      s.delete_suffix!('ello').should equal(s)
-      s.should == 'h'
-    end
+describe "String#delete_suffix!" do
+  it "removes the found prefix" do
+    s = 'hello'
+    s.delete_suffix!('ello').should equal(s)
+    s.should == 'h'
+  end
 
-    it "returns nil if no change is made" do
-      s = 'hello'
-      s.delete_suffix!('ell').should == nil
-      s.delete_suffix!('').should == nil
-    end
+  it "returns nil if no change is made" do
+    s = 'hello'
+    s.delete_suffix!('ell').should == nil
+    s.delete_suffix!('').should == nil
+  end
 
-    it "doesn't set $~" do
-      $~ = nil
+  it "doesn't set $~" do
+    $~ = nil
 
-      'hello'.delete_suffix!('ello')
-      $~.should == nil
-    end
+    'hello'.delete_suffix!('ello')
+    $~.should == nil
+  end
 
-    it "calls to_str on its argument" do
-      o = mock('x')
-      o.should_receive(:to_str).and_return 'ello'
-      'hello'.delete_suffix!(o).should == 'h'
-    end
+  it "calls to_str on its argument" do
+    o = mock('x')
+    o.should_receive(:to_str).and_return 'ello'
+    'hello'.delete_suffix!(o).should == 'h'
+  end
 
-    it "raises a FrozenError when self is frozen" do
-      -> { 'hello'.freeze.delete_suffix!('ello') }.should raise_error(FrozenError)
-      -> { 'hello'.freeze.delete_suffix!('') }.should raise_error(FrozenError)
-      -> { ''.freeze.delete_suffix!('') }.should raise_error(FrozenError)
-    end
+  it "raises a FrozenError when self is frozen" do
+    -> { 'hello'.freeze.delete_suffix!('ello') }.should raise_error(FrozenError)
+    -> { 'hello'.freeze.delete_suffix!('') }.should raise_error(FrozenError)
+    -> { ''.freeze.delete_suffix!('') }.should raise_error(FrozenError)
   end
 end
diff --git a/spec/ruby/core/string/each_grapheme_cluster_spec.rb b/spec/ruby/core/string/each_grapheme_cluster_spec.rb
index 5367f84887..632f2337f1 100644
--- a/spec/ruby/core/string/each_grapheme_cluster_spec.rb
+++ b/spec/ruby/core/string/each_grapheme_cluster_spec.rb
@@ -2,10 +2,8 @@ require_relative 'shared/chars'
 require_relative 'shared/grapheme_clusters'
 require_relative 'shared/each_char_without_block'
 
-ruby_version_is "2.5" do
-  describe "String#each_grapheme_cluster" do
-    it_behaves_like :string_chars, :each_grapheme_cluster
-    it_behaves_like :string_grapheme_clusters, :each_grapheme_cluster
-    it_behaves_like :string_each_char_without_block, :each_grapheme_cluster
-  end
+describe "String#each_grapheme_cluster" do
+  it_behaves_like :string_chars, :each_grapheme_cluster
+  it_behaves_like :string_grapheme_clusters, :each_grapheme_cluster
+  it_behaves_like :string_each_char_without_block, :each_grapheme_cluster
 end
diff --git a/spec/ruby/core/string/grapheme_clusters_spec.rb b/spec/ruby/core/string/grapheme_clusters_spec.rb
index 0cba0e4216..3046265a12 100644
--- a/spec/ruby/core/string/grapheme_clusters_spec.rb
+++ b/spec/ruby/core/string/grapheme_clusters_spec.rb
@@ -1,15 +1,13 @@
 require_relative 'shared/chars'
 require_relative 'shared/grapheme_clusters'
 
-ruby_version_is "2.5" do
-  describe "String#grapheme_clusters" do
-    it_behaves_like :string_chars, :grapheme_clusters
-    it_behaves_like :string_grapheme_clusters, :grapheme_clusters
+describe "String#grapheme_clusters" do
+  it_behaves_like :string_chars, :grapheme_clusters
+  it_behaves_like :string_grapheme_clusters, :grapheme_clusters
 
-    it "returns an array when no block given" do
-      string = "ab\u{1f3f3}\u{fe0f}\u{200d}\u{1f308}\u{1F43E}"
-      string.grapheme_clusters.should == ['a', 'b', "\u{1f3f3}\u{fe0f}\u{200d}\u{1f308}", "\u{1F43E}"]
+  it "returns an array when no block given" do
+    string = "ab\u{1f3f3}\u{fe0f}\u{200d}\u{1f308}\u{1F43E}"
+    string.grapheme_clusters.should == ['a', 'b', "\u{1f3f3}\u{fe0f}\u{200d}\u{1f308}", "\u{1F43E}"]
 
-    end
   end
 end
diff --git a/spec/ruby/core/string/modulo_spec.rb b/spec/ruby/core/string/modulo_spec.rb
index 35ee0b16f5..ad4b85e3c3 100644
--- a/spec/ruby/core/string/modulo_spec.rb
+++ b/spec/ruby/core/string/modulo_spec.rb
@@ -50,18 +50,9 @@ describe "String#%" do
     end
   end
 
-  ruby_version_is ""..."2.5" do
-    it "formats single % character at the end as literal %" do
-      ("%" % []).should == "%"
-      ("foo%" % []).should == "foo%"
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "raises an error if single % appears at the end" do
-      -> { ("%" % []) }.should raise_error(ArgumentError)
-      -> { ("foo%" % [])}.should raise_error(ArgumentError)
-    end
+  it "raises an error if single % appears at the end" do
+    -> { ("%" % []) }.should raise_error(ArgumentError)
+    -> { ("foo%" % [])}.should raise_error(ArgumentError)
   end
 
   it "formats single % character before a newline as literal %" do
diff --git a/spec/ruby/core/string/shared/each_line.rb b/spec/ruby/core/string/shared/each_line.rb
index d8c48054c4..c82e63cfe8 100644
--- a/spec/ruby/core/string/shared/each_line.rb
+++ b/spec/ruby/core/string/shared/each_line.rb
@@ -54,28 +54,14 @@ describe :string_each_line, shared: true do
     a.should == ["one\ntwo\r\nthree"]
   end
 
-  ruby_version_is ''...'2.5' do
-    it "yields paragraphs (broken by 2 or more successive newlines) when passed ''" do
-      a = []
-      "hello\nworld\n\n\nand\nuniverse\n\n\n\n\n".send(@method, '') { |s| a << s }
-      a.should == ["hello\nworld\n\n\n", "and\nuniverse\n\n\n\n\n"]
-
-      a = []
-      "hello\nworld\n\n\nand\nuniverse\n\n\n\n\ndog".send(@method, '') { |s| a << s }
-      a.should == ["hello\nworld\n\n\n", "and\nuniverse\n\n\n\n\n", "dog"]
-    end
-  end
-
-  ruby_version_is '2.5' do
-    it "yields paragraphs (broken by 2 or more successive newlines) when passed '' and replaces multiple newlines with only two ones" do
-      a = []
-      "hello\nworld\n\n\nand\nuniverse\n\n\n\n\n".send(@method, '') { |s| a << s }
-      a.should == ["hello\nworld\n\n", "and\nuniverse\n\n"]
+  it "yields paragraphs (broken by 2 or more successive newlines) when passed '' and replaces multiple newlines with only two ones" do
+    a = []
+    "hello\nworld\n\n\nand\nuniverse\n\n\n\n\n".send(@method, '') { |s| a << s }
+    a.should == ["hello\nworld\n\n", "and\nuniverse\n\n"]
 
-      a = []
-      "hello\nworld\n\n\nand\nuniverse\n\n\n\n\ndog".send(@method, '') { |s| a << s }
-      a.should == ["hello\nworld\n\n", "and\nuniverse\n\n", "dog"]
-    end
+    a = []
+    "hello\nworld\n\n\nand\nuniverse\n\n\n\n\ndog".send(@method, '') { |s| a << s }
+    a.should == ["hello\nworld\n\n", "and\nuniverse\n\n", "dog"]
   end
 
   describe "uses $/" do
diff --git a/spec/ruby/core/string/start_with_spec.rb b/spec/ruby/core/string/start_with_spec.rb
index 1000db180c..11c8041925 100644
--- a/spec/ruby/core/string/start_with_spec.rb
+++ b/spec/ruby/core/string/start_with_spec.rb
@@ -43,34 +43,32 @@ describe "String#start_with?" do
     "céréale".should.start_with?("cér")
   end
 
-  ruby_version_is "2.5" do
-    it "supports regexps" do
-      regexp = /[h1]/
-      "hello".should.start_with?(regexp)
-      "1337".should.start_with?(regexp)
-      "foxes are 1337".should_not.start_with?(regexp)
-      "chunky\n12bacon".should_not.start_with?(/12/)
-    end
+  it "supports regexps" do
+    regexp = /[h1]/
+    "hello".should.start_with?(regexp)
+    "1337".should.start_with?(regexp)
+    "foxes are 1337".should_not.start_with?(regexp)
+    "chunky\n12bacon".should_not.start_with?(/12/)
+  end
 
-    it "supports regexps with ^ and $ modifiers" do
-      regexp1 = /^\d{2}/
-      regexp2 = /\d{2}$/
-      "12test".should.start_with?(regexp1)
-      "test12".should_not.start_with?(regexp1)
-      "12test".should_not.start_with?(regexp2)
-      "test12".should_not.start_with?(regexp2)
-    end
+  it "supports regexps with ^ and $ modifiers" do
+    regexp1 = /^\d{2}/
+    regexp2 = /\d{2}$/
+    "12test".should.start_with?(regexp1)
+    "test12".should_not.start_with?(regexp1)
+    "12test".should_not.start_with?(regexp2)
+    "test12".should_not.start_with?(regexp2)
+  end
 
-    it "sets Regexp.last_match if it returns true" do
-      regexp = /test-(\d+)/
-      "test-1337".start_with?(regexp).should be_true
-      Regexp.last_match.should_not be_nil
-      Regexp.last_match[1].should == "1337"
-      $1.should == "1337"
+  it "sets Regexp.last_match if it returns true" do
+    regexp = /test-(\d+)/
+    "test-1337".start_with?(regexp).should be_true
+    Regexp.last_match.should_not be_nil
+    Regexp.last_match[1].should == "1337"
+    $1.should == "1337"
 
-      "test-asdf".start_with?(regexp).should be_false
-      Regexp.last_match.should be_nil
-      $1.should be_nil
-    end
+    "test-asdf".start_with?(regexp).should be_false
+    Regexp.last_match.should be_nil
+    $1.should be_nil
   end
 end
diff --git a/spec/ruby/core/string/uminus_spec.rb b/spec/ruby/core/string/uminus_spec.rb
index dace04846c..85b484b6df 100644
--- a/spec/ruby/core/string/uminus_spec.rb
+++ b/spec/ruby/core/string/uminus_spec.rb
@@ -18,22 +18,20 @@ describe 'String#-@' do
     output.should == 'foo'
   end
 
-  ruby_version_is "2.5" do
-    it "returns the same object for equal unfrozen strings" do
-      origin = "this is a string"
-      dynamic = %w(this is a string).join(' ')
+  it "returns the same object for equal unfrozen strings" do
+    origin = "this is a string"
+    dynamic = %w(this is a string).join(' ')
 
-      origin.should_not equal(dynamic)
-      (-origin).should equal(-dynamic)
-    end
+    origin.should_not equal(dynamic)
+    (-origin).should equal(-dynamic)
+  end
 
-    it "returns the same object when it's called on the same String literal" do
-      (-"unfrozen string").should equal(-"unfrozen string")
-      (-"unfrozen string").should_not equal(-"another unfrozen string")
-    end
+  it "returns the same object when it's called on the same String literal" do
+    (-"unfrozen string").should equal(-"unfrozen string")
+    (-"unfrozen string").should_not equal(-"another unfrozen string")
   end
 
-  ruby_version_is "2.5"..."2.6" do
+  ruby_version_is ""..."2.6" do
     it "does not deduplicate already frozen strings" do
       dynamic = %w(this string is frozen).join(' ').freeze
 
diff --git a/spec/ruby/core/string/undump_spec.rb b/spec/ruby/core/string/undump_spec.rb
index d45c4bae1b..81deb6fa58 100644
--- a/spec/ruby/core/string/undump_spec.rb
+++ b/spec/ruby/core/string/undump_spec.rb
@@ -2,452 +2,450 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 
-ruby_version_is '2.5' do
-  describe "String#undump" do
-    ruby_version_is ''...'2.7' do
-      it "taints the result if self is tainted" do
-        '"foo"'.taint.undump.tainted?.should == true
-      end
-
-      it "untrusts the result if self is untrusted" do
-        '"foo"'.untrust.undump.untrusted?.should == true
-      end
+describe "String#undump" do
+  ruby_version_is ''...'2.7' do
+    it "taints the result if self is tainted" do
+      '"foo"'.taint.undump.tainted?.should == true
     end
 
-    it "does not take into account if a string is frozen" do
-      '"foo"'.freeze.undump.frozen?.should == false
+    it "untrusts the result if self is untrusted" do
+      '"foo"'.untrust.undump.untrusted?.should == true
     end
+  end
 
-    it "always returns String instance" do
-      StringSpecs::MyString.new('"foo"').undump.should be_an_instance_of(String)
-    end
+  it "does not take into account if a string is frozen" do
+    '"foo"'.freeze.undump.frozen?.should == false
+  end
 
-    it "strips outer \"" do
-      '"foo"'.undump.should == 'foo'
-    end
+  it "always returns String instance" do
+    StringSpecs::MyString.new('"foo"').undump.should be_an_instance_of(String)
+  end
 
-    it "returns a string with special characters in \\<char> notation replaced with the characters" do
-      [ ['"\\a"', "\a"],
-        ['"\\b"', "\b"],
-        ['"\\t"', "\t"],
-        ['"\\n"', "\n"],
-        ['"\\v"', "\v"],
-        ['"\\f"', "\f"],
-        ['"\\r"', "\r"],
-        ['"\\e"', "\e"]
-      ].should be_computed_by(:undump)
-    end
+  it "strips outer \"" do
+    '"foo"'.undump.should == 'foo'
+  end
 
-    it "returns a string with unescaped sequences \" and \\" do
-      [ ['"\\""' , "\""],
-        ['"\\\\"', "\\"]
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with special characters in \\<char> notation replaced with the characters" do
+    [ ['"\\a"', "\a"],
+      ['"\\b"', "\b"],
+      ['"\\t"', "\t"],
+      ['"\\n"', "\n"],
+      ['"\\v"', "\v"],
+      ['"\\f"', "\f"],
+      ['"\\r"', "\r"],
+      ['"\\e"', "\e"]
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with unescaped sequences \\#<char> when # is followed by $, @, {" do
-      [ ['"\\#$PATH"', "\#$PATH"],
-        ['"\\#@a"',    "\#@a"],
-        ['"\\#@@a"',   "\#@@a"],
-        ['"\\#{a}"',   "\#{a}"]
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with unescaped sequences \" and \\" do
+    [ ['"\\""' , "\""],
+      ['"\\\\"', "\\"]
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with # not escaped when followed by any other character" do
-      [ ['"#"', '#'],
-        ['"#1"', '#1']
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with unescaped sequences \\#<char> when # is followed by $, @, {" do
+    [ ['"\\#$PATH"', "\#$PATH"],
+      ['"\\#@a"',    "\#@a"],
+      ['"\\#@@a"',   "\#@@a"],
+      ['"\\#{a}"',   "\#{a}"]
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with printable non-alphanumeric characters" do
-      [ ['" "', ' '],
-        ['"!"', '!'],
-        ['"$"', '$'],
-        ['"%"', '%'],
-        ['"&"', '&'],
-        ['"\'"', '\''],
-        ['"("', '('],
-        ['")"', ')'],
-        ['"*"', '*'],
-        ['"+"', '+'],
-        ['","', ','],
-        ['"-"', '-'],
-        ['"."', '.'],
-        ['"/"', '/'],
-        ['":"', ':'],
-        ['";"', ';'],
-        ['"<"', '<'],
-        ['"="', '='],
-        ['">"', '>'],
-        ['"?"', '?'],
-        ['"@"', '@'],
-        ['"["', '['],
-        ['"]"', ']'],
-        ['"^"', '^'],
-        ['"_"', '_'],
-        ['"`"', '`'],
-        ['"{"', '{'],
-        ['"|"', '|'],
-        ['"}"', '}'],
-        ['"~"', '~']
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with # not escaped when followed by any other character" do
+    [ ['"#"', '#'],
+      ['"#1"', '#1']
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with numeric characters unescaped" do
-      [ ['"0"', "0"],
-        ['"1"', "1"],
-        ['"2"', "2"],
-        ['"3"', "3"],
-        ['"4"', "4"],
-        ['"5"', "5"],
-        ['"6"', "6"],
-        ['"7"', "7"],
-        ['"8"', "8"],
-        ['"9"', "9"],
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with printable non-alphanumeric characters" do
+    [ ['" "', ' '],
+      ['"!"', '!'],
+      ['"$"', '$'],
+      ['"%"', '%'],
+      ['"&"', '&'],
+      ['"\'"', '\''],
+      ['"("', '('],
+      ['")"', ')'],
+      ['"*"', '*'],
+      ['"+"', '+'],
+      ['","', ','],
+      ['"-"', '-'],
+      ['"."', '.'],
+      ['"/"', '/'],
+      ['":"', ':'],
+      ['";"', ';'],
+      ['"<"', '<'],
+      ['"="', '='],
+      ['">"', '>'],
+      ['"?"', '?'],
+      ['"@"', '@'],
+      ['"["', '['],
+      ['"]"', ']'],
+      ['"^"', '^'],
+      ['"_"', '_'],
+      ['"`"', '`'],
+      ['"{"', '{'],
+      ['"|"', '|'],
+      ['"}"', '}'],
+      ['"~"', '~']
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with upper-case alpha characters unescaped" do
-      [ ['"A"', 'A'],
-        ['"B"', 'B'],
-        ['"C"', 'C'],
-        ['"D"', 'D'],
-        ['"E"', 'E'],
-        ['"F"', 'F'],
-        ['"G"', 'G'],
-        ['"H"', 'H'],
-        ['"I"', 'I'],
-        ['"J"', 'J'],
-        ['"K"', 'K'],
-        ['"L"', 'L'],
-        ['"M"', 'M'],
-        ['"N"', 'N'],
-        ['"O"', 'O'],
-        ['"P"', 'P'],
-        ['"Q"', 'Q'],
-        ['"R"', 'R'],
-        ['"S"', 'S'],
-        ['"T"', 'T'],
-        ['"U"', 'U'],
-        ['"V"', 'V'],
-        ['"W"', 'W'],
-        ['"X"', 'X'],
-        ['"Y"', 'Y'],
-        ['"Z"', 'Z']
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with numeric characters unescaped" do
+    [ ['"0"', "0"],
+      ['"1"', "1"],
+      ['"2"', "2"],
+      ['"3"', "3"],
+      ['"4"', "4"],
+      ['"5"', "5"],
+      ['"6"', "6"],
+      ['"7"', "7"],
+      ['"8"', "8"],
+      ['"9"', "9"],
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with lower-case alpha characters unescaped" do
-      [ ['"a"', 'a'],
-        ['"b"', 'b'],
-        ['"c"', 'c'],
-        ['"d"', 'd'],
-        ['"e"', 'e'],
-        ['"f"', 'f'],
-        ['"g"', 'g'],
-        ['"h"', 'h'],
-        ['"i"', 'i'],
-        ['"j"', 'j'],
-        ['"k"', 'k'],
-        ['"l"', 'l'],
-        ['"m"', 'm'],
-        ['"n"', 'n'],
-        ['"o"', 'o'],
-        ['"p"', 'p'],
-        ['"q"', 'q'],
-        ['"r"', 'r'],
-        ['"s"', 's'],
-        ['"t"', 't'],
-        ['"u"', 'u'],
-        ['"v"', 'v'],
-        ['"w"', 'w'],
-        ['"x"', 'x'],
-        ['"y"', 'y'],
-        ['"z"', 'z']
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with upper-case alpha characters unescaped" do
+    [ ['"A"', 'A'],
+      ['"B"', 'B'],
+      ['"C"', 'C'],
+      ['"D"', 'D'],
+      ['"E"', 'E'],
+      ['"F"', 'F'],
+      ['"G"', 'G'],
+      ['"H"', 'H'],
+      ['"I"', 'I'],
+      ['"J"', 'J'],
+      ['"K"', 'K'],
+      ['"L"', 'L'],
+      ['"M"', 'M'],
+      ['"N"', 'N'],
+      ['"O"', 'O'],
+      ['"P"', 'P'],
+      ['"Q"', 'Q'],
+      ['"R"', 'R'],
+      ['"S"', 'S'],
+      ['"T"', 'T'],
+      ['"U"', 'U'],
+      ['"V"', 'V'],
+      ['"W"', 'W'],
+      ['"X"', 'X'],
+      ['"Y"', 'Y'],
+      ['"Z"', 'Z']
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with \\x notation replaced with non-printing ASCII character" do
-      [ ['"\\x00"', 0000.chr.force_encoding('utf-8')],
-        ['"\\x01"', 0001.chr.force_encoding('utf-8')],
-        ['"\\x02"', 0002.chr.force_encoding('utf-8')],
-        ['"\\x03"', 0003.chr.force_encoding('utf-8')],
-        ['"\\x04"', 0004.chr.force_encoding('utf-8')],
-        ['"\\x05"', 0005.chr.force_encoding('utf-8')],
-        ['"\\x06"', 0006.chr.force_encoding('utf-8')],
-        ['"\\x0E"', 0016.chr.force_encoding('utf-8')],
-        ['"\\x0F"', 0017.chr.force_encoding('utf-8')],
-        ['"\\x10"', 0020.chr.force_encoding('utf-8')],
-        ['"\\x11"', 0021.chr.force_encoding('utf-8')],
-        ['"\\x12"', 0022.chr.force_encoding('utf-8')],
-        ['"\\x13"', 0023.chr.force_encoding('utf-8')],
-        ['"\\x14"', 0024.chr.force_encoding('utf-8')],
-        ['"\\x15"', 0025.chr.force_encoding('utf-8')],
-        ['"\\x16"', 0026.chr.force_encoding('utf-8')],
-        ['"\\x17"', 0027.chr.force_encoding('utf-8')],
-        ['"\\x18"', 0030.chr.force_encoding('utf-8')],
-        ['"\\x19"', 0031.chr.force_encoding('utf-8')],
-        ['"\\x1A"', 0032.chr.force_encoding('utf-8')],
-        ['"\\x1C"', 0034.chr.force_encoding('utf-8')],
-        ['"\\x1D"', 0035.chr.force_encoding('utf-8')],
-        ['"\\x1E"', 0036.chr.force_encoding('utf-8')],
-        ['"\\x1F"', 0037.chr.force_encoding('utf-8')],
-        ['"\\x7F"', 0177.chr.force_encoding('utf-8')],
-        ['"\\x80"', 0200.chr.force_encoding('utf-8')],
-        ['"\\x81"', 0201.chr.force_encoding('utf-8')],
-        ['"\\x82"', 0202.chr.force_encoding('utf-8')],
-        ['"\\x83"', 0203.chr.force_encoding('utf-8')],
-        ['"\\x84"', 0204.chr.force_encoding('utf-8')],
-        ['"\\x85"', 0205.chr.force_encoding('utf-8')],
-        ['"\\x86"', 0206.chr.force_encoding('utf-8')],
-        ['"\\x87"', 0207.chr.force_encoding('utf-8')],
-        ['"\\x88"', 0210.chr.force_encoding('utf-8')],
-        ['"\\x89"', 0211.chr.force_encoding('utf-8')],
-        ['"\\x8A"', 0212.chr.force_encoding('utf-8')],
-        ['"\\x8B"', 0213.chr.force_encoding('utf-8')],
-        ['"\\x8C"', 0214.chr.force_encoding('utf-8')],
-        ['"\\x8D"', 0215.chr.force_encoding('utf-8')],
-        ['"\\x8E"', 0216.chr.force_encoding('utf-8')],
-        ['"\\x8F"', 0217.chr.force_encoding('utf-8')],
-        ['"\\x90"', 0220.chr.force_encoding('utf-8')],
-        ['"\\x91"', 0221.chr.force_encoding('utf-8')],
-        ['"\\x92"', 0222.chr.force_encoding('utf-8')],
-        ['"\\x93"', 0223.chr.force_encoding('utf-8')],
-        ['"\\x94"', 0224.chr.force_encoding('utf-8')],
-        ['"\\x95"', 0225.chr.force_encoding('utf-8')],
-        ['"\\x96"', 0226.chr.force_encoding('utf-8')],
-        ['"\\x97"', 0227.chr.force_encoding('utf-8')],
-        ['"\\x98"', 0230.chr.force_encoding('utf-8')],
-        ['"\\x99"', 0231.chr.force_encoding('utf-8')],
-        ['"\\x9A"', 0232.chr.force_encoding('utf-8')],
-        ['"\\x9B"', 0233.chr.force_encoding('utf-8')],
-        ['"\\x9C"', 0234.chr.force_encoding('utf-8')],
-        ['"\\x9D"', 0235.chr.force_encoding('utf-8')],
-        ['"\\x9E"', 0236.chr.force_encoding('utf-8')],
-        ['"\\x9F"', 0237.chr.force_encoding('utf-8')],
-        ['"\\xA0"', 0240.chr.force_encoding('utf-8')],
-        ['"\\xA1"', 0241.chr.force_encoding('utf-8')],
-        ['"\\xA2"', 0242.chr.force_encoding('utf-8')],
-        ['"\\xA3"', 0243.chr.force_encoding('utf-8')],
-        ['"\\xA4"', 0244.chr.force_encoding('utf-8')],
-        ['"\\xA5"', 0245.chr.force_encoding('utf-8')],
-        ['"\\xA6"', 0246.chr.force_encoding('utf-8')],
-        ['"\\xA7"', 0247.chr.force_encoding('utf-8')],
-        ['"\\xA8"', 0250.chr.force_encoding('utf-8')],
-        ['"\\xA9"', 0251.chr.force_encoding('utf-8')],
-        ['"\\xAA"', 0252.chr.force_encoding('utf-8')],
-        ['"\\xAB"', 0253.chr.force_encoding('utf-8')],
-        ['"\\xAC"', 0254.chr.force_encoding('utf-8')],
-        ['"\\xAD"', 0255.chr.force_encoding('utf-8')],
-        ['"\\xAE"', 0256.chr.force_encoding('utf-8')],
-        ['"\\xAF"', 0257.chr.force_encoding('utf-8')],
-        ['"\\xB0"', 0260.chr.force_encoding('utf-8')],
-        ['"\\xB1"', 0261.chr.force_encoding('utf-8')],
-        ['"\\xB2"', 0262.chr.force_encoding('utf-8')],
-        ['"\\xB3"', 0263.chr.force_encoding('utf-8')],
-        ['"\\xB4"', 0264.chr.force_encoding('utf-8')],
-        ['"\\xB5"', 0265.chr.force_encoding('utf-8')],
-        ['"\\xB6"', 0266.chr.force_encoding('utf-8')],
-        ['"\\xB7"', 0267.chr.force_encoding('utf-8')],
-        ['"\\xB8"', 0270.chr.force_encoding('utf-8')],
-        ['"\\xB9"', 0271.chr.force_encoding('utf-8')],
-        ['"\\xBA"', 0272.chr.force_encoding('utf-8')],
-        ['"\\xBB"', 0273.chr.force_encoding('utf-8')],
-        ['"\\xBC"', 0274.chr.force_encoding('utf-8')],
-        ['"\\xBD"', 0275.chr.force_encoding('utf-8')],
-        ['"\\xBE"', 0276.chr.force_encoding('utf-8')],
-        ['"\\xBF"', 0277.chr.force_encoding('utf-8')],
-        ['"\\xC0"', 0300.chr.force_encoding('utf-8')],
-        ['"\\xC1"', 0301.chr.force_encoding('utf-8')],
-        ['"\\xC2"', 0302.chr.force_encoding('utf-8')],
-        ['"\\xC3"', 0303.chr.force_encoding('utf-8')],
-        ['"\\xC4"', 0304.chr.force_encoding('utf-8')],
-        ['"\\xC5"', 0305.chr.force_encoding('utf-8')],
-        ['"\\xC6"', 0306.chr.force_encoding('utf-8')],
-        ['"\\xC7"', 0307.chr.force_encoding('utf-8')],
-        ['"\\xC8"', 0310.chr.force_encoding('utf-8')],
-        ['"\\xC9"', 0311.chr.force_encoding('utf-8')],
-        ['"\\xCA"', 0312.chr.force_encoding('utf-8')],
-        ['"\\xCB"', 0313.chr.force_encoding('utf-8')],
-        ['"\\xCC"', 0314.chr.force_encoding('utf-8')],
-        ['"\\xCD"', 0315.chr.force_encoding('utf-8')],
-        ['"\\xCE"', 0316.chr.force_encoding('utf-8')],
-        ['"\\xCF"', 0317.chr.force_encoding('utf-8')],
-        ['"\\xD0"', 0320.chr.force_encoding('utf-8')],
-        ['"\\xD1"', 0321.chr.force_encoding('utf-8')],
-        ['"\\xD2"', 0322.chr.force_encoding('utf-8')],
-        ['"\\xD3"', 0323.chr.force_encoding('utf-8')],
-        ['"\\xD4"', 0324.chr.force_encoding('utf-8')],
-        ['"\\xD5"', 0325.chr.force_encoding('utf-8')],
-        ['"\\xD6"', 0326.chr.force_encoding('utf-8')],
-        ['"\\xD7"', 0327.chr.force_encoding('utf-8')],
-        ['"\\xD8"', 0330.chr.force_encoding('utf-8')],
-        ['"\\xD9"', 0331.chr.force_encoding('utf-8')],
-        ['"\\xDA"', 0332.chr.force_encoding('utf-8')],
-        ['"\\xDB"', 0333.chr.force_encoding('utf-8')],
-        ['"\\xDC"', 0334.chr.force_encoding('utf-8')],
-        ['"\\xDD"', 0335.chr.force_encoding('utf-8')],
-        ['"\\xDE"', 0336.chr.force_encoding('utf-8')],
-        ['"\\xDF"', 0337.chr.force_encoding('utf-8')],
-        ['"\\xE0"', 0340.chr.force_encoding('utf-8')],
-        ['"\\xE1"', 0341.chr.force_encoding('utf-8')],
-        ['"\\xE2"', 0342.chr.force_encoding('utf-8')],
-        ['"\\xE3"', 0343.chr.force_encoding('utf-8')],
-        ['"\\xE4"', 0344.chr.force_encoding('utf-8')],
-        ['"\\xE5"', 0345.chr.force_encoding('utf-8')],
-        ['"\\xE6"', 0346.chr.force_encoding('utf-8')],
-        ['"\\xE7"', 0347.chr.force_encoding('utf-8')],
-        ['"\\xE8"', 0350.chr.force_encoding('utf-8')],
-        ['"\\xE9"', 0351.chr.force_encoding('utf-8')],
-        ['"\\xEA"', 0352.chr.force_encoding('utf-8')],
-        ['"\\xEB"', 0353.chr.force_encoding('utf-8')],
-        ['"\\xEC"', 0354.chr.force_encoding('utf-8')],
-        ['"\\xED"', 0355.chr.force_encoding('utf-8')],
-        ['"\\xEE"', 0356.chr.force_encoding('utf-8')],
-        ['"\\xEF"', 0357.chr.force_encoding('utf-8')],
-        ['"\\xF0"', 0360.chr.force_encoding('utf-8')],
-        ['"\\xF1"', 0361.chr.force_encoding('utf-8')],
-        ['"\\xF2"', 0362.chr.force_encoding('utf-8')],
-        ['"\\xF3"', 0363.chr.force_encoding('utf-8')],
-        ['"\\xF4"', 0364.chr.force_encoding('utf-8')],
-        ['"\\xF5"', 0365.chr.force_encoding('utf-8')],
-        ['"\\xF6"', 0366.chr.force_encoding('utf-8')],
-        ['"\\xF7"', 0367.chr.force_encoding('utf-8')],
-        ['"\\xF8"', 0370.chr.force_encoding('utf-8')],
-        ['"\\xF9"', 0371.chr.force_encoding('utf-8')],
-        ['"\\xFA"', 0372.chr.force_encoding('utf-8')],
-        ['"\\xFB"', 0373.chr.force_encoding('utf-8')],
-        ['"\\xFC"', 0374.chr.force_encoding('utf-8')],
-        ['"\\xFD"', 0375.chr.force_encoding('utf-8')],
-        ['"\\xFE"', 0376.chr.force_encoding('utf-8')],
-        ['"\\xFF"', 0377.chr.force_encoding('utf-8')]
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with lower-case alpha characters unescaped" do
+    [ ['"a"', 'a'],
+      ['"b"', 'b'],
+      ['"c"', 'c'],
+      ['"d"', 'd'],
+      ['"e"', 'e'],
+      ['"f"', 'f'],
+      ['"g"', 'g'],
+      ['"h"', 'h'],
+      ['"i"', 'i'],
+      ['"j"', 'j'],
+      ['"k"', 'k'],
+      ['"l"', 'l'],
+      ['"m"', 'm'],
+      ['"n"', 'n'],
+      ['"o"', 'o'],
+      ['"p"', 'p'],
+      ['"q"', 'q'],
+      ['"r"', 'r'],
+      ['"s"', 's'],
+      ['"t"', 't'],
+      ['"u"', 'u'],
+      ['"v"', 'v'],
+      ['"w"', 'w'],
+      ['"x"', 'x'],
+      ['"y"', 'y'],
+      ['"z"', 'z']
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with \\u{} notation replaced with multi-byte UTF-8 characters" do
-      [ ['"\u{80}"', 0200.chr('utf-8')],
-        ['"\u{81}"', 0201.chr('utf-8')],
-        ['"\u{82}"', 0202.chr('utf-8')],
-        ['"\u{83}"', 0203.chr('utf-8')],
-        ['"\u{84}"', 0204.chr('utf-8')],
-        ['"\u{86}"', 0206.chr('utf-8')],
-        ['"\u{87}"', 0207.chr('utf-8')],
-        ['"\u{88}"', 0210.chr('utf-8')],
-        ['"\u{89}"', 0211.chr('utf-8')],
-        ['"\u{8a}"', 0212.chr('utf-8')],
-        ['"\u{8b}"', 0213.chr('utf-8')],
-        ['"\u{8c}"', 0214.chr('utf-8')],
-        ['"\u{8d}"', 0215.chr('utf-8')],
-        ['"\u{8e}"', 0216.chr('utf-8')],
-        ['"\u{8f}"', 0217.chr('utf-8')],
-        ['"\u{90}"', 0220.chr('utf-8')],
-        ['"\u{91}"', 0221.chr('utf-8')],
-        ['"\u{92}"', 0222.chr('utf-8')],
-        ['"\u{93}"', 0223.chr('utf-8')],
-        ['"\u{94}"', 0224.chr('utf-8')],
-        ['"\u{95}"', 0225.chr('utf-8')],
-        ['"\u{96}"', 0226.chr('utf-8')],
-        ['"\u{97}"', 0227.chr('utf-8')],
-        ['"\u{98}"', 0230.chr('utf-8')],
-        ['"\u{99}"', 0231.chr('utf-8')],
-        ['"\u{9a}"', 0232.chr('utf-8')],
-        ['"\u{9b}"', 0233.chr('utf-8')],
-        ['"\u{9c}"', 0234.chr('utf-8')],
-        ['"\u{9d}"', 0235.chr('utf-8')],
-        ['"\u{9e}"', 0236.chr('utf-8')],
-        ['"\u{9f}"', 0237.chr('utf-8')],
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with \\x notation replaced with non-printing ASCII character" do
+    [ ['"\\x00"', 0000.chr.force_encoding('utf-8')],
+      ['"\\x01"', 0001.chr.force_encoding('utf-8')],
+      ['"\\x02"', 0002.chr.force_encoding('utf-8')],
+      ['"\\x03"', 0003.chr.force_encoding('utf-8')],
+      ['"\\x04"', 0004.chr.force_encoding('utf-8')],
+      ['"\\x05"', 0005.chr.force_encoding('utf-8')],
+      ['"\\x06"', 0006.chr.force_encoding('utf-8')],
+      ['"\\x0E"', 0016.chr.force_encoding('utf-8')],
+      ['"\\x0F"', 0017.chr.force_encoding('utf-8')],
+      ['"\\x10"', 0020.chr.force_encoding('utf-8')],
+      ['"\\x11"', 0021.chr.force_encoding('utf-8')],
+      ['"\\x12"', 0022.chr.force_encoding('utf-8')],
+      ['"\\x13"', 0023.chr.force_encoding('utf-8')],
+      ['"\\x14"', 0024.chr.force_encoding('utf-8')],
+      ['"\\x15"', 0025.chr.force_encoding('utf-8')],
+      ['"\\x16"', 0026.chr.force_encoding('utf-8')],
+      ['"\\x17"', 0027.chr.force_encoding('utf-8')],
+      ['"\\x18"', 0030.chr.force_encoding('utf-8')],
+      ['"\\x19"', 0031.chr.force_encoding('utf-8')],
+      ['"\\x1A"', 0032.chr.force_encoding('utf-8')],
+      ['"\\x1C"', 0034.chr.force_encoding('utf-8')],
+      ['"\\x1D"', 0035.chr.force_encoding('utf-8')],
+      ['"\\x1E"', 0036.chr.force_encoding('utf-8')],
+      ['"\\x1F"', 0037.chr.force_encoding('utf-8')],
+      ['"\\x7F"', 0177.chr.force_encoding('utf-8')],
+      ['"\\x80"', 0200.chr.force_encoding('utf-8')],
+      ['"\\x81"', 0201.chr.force_encoding('utf-8')],
+      ['"\\x82"', 0202.chr.force_encoding('utf-8')],
+      ['"\\x83"', 0203.chr.force_encoding('utf-8')],
+      ['"\\x84"', 0204.chr.force_encoding('utf-8')],
+      ['"\\x85"', 0205.chr.force_encoding('utf-8')],
+      ['"\\x86"', 0206.chr.force_encoding('utf-8')],
+      ['"\\x87"', 0207.chr.force_encoding('utf-8')],
+      ['"\\x88"', 0210.chr.force_encoding('utf-8')],
+      ['"\\x89"', 0211.chr.force_encoding('utf-8')],
+      ['"\\x8A"', 0212.chr.force_encoding('utf-8')],
+      ['"\\x8B"', 0213.chr.force_encoding('utf-8')],
+      ['"\\x8C"', 0214.chr.force_encoding('utf-8')],
+      ['"\\x8D"', 0215.chr.force_encoding('utf-8')],
+      ['"\\x8E"', 0216.chr.force_encoding('utf-8')],
+      ['"\\x8F"', 0217.chr.force_encoding('utf-8')],
+      ['"\\x90"', 0220.chr.force_encoding('utf-8')],
+      ['"\\x91"', 0221.chr.force_encoding('utf-8')],
+      ['"\\x92"', 0222.chr.force_encoding('utf-8')],
+      ['"\\x93"', 0223.chr.force_encoding('utf-8')],
+      ['"\\x94"', 0224.chr.force_encoding('utf-8')],
+      ['"\\x95"', 0225.chr.force_encoding('utf-8')],
+      ['"\\x96"', 0226.chr.force_encoding('utf-8')],
+      ['"\\x97"', 0227.chr.force_encoding('utf-8')],
+      ['"\\x98"', 0230.chr.force_encoding('utf-8')],
+      ['"\\x99"', 0231.chr.force_encoding('utf-8')],
+      ['"\\x9A"', 0232.chr.force_encoding('utf-8')],
+      ['"\\x9B"', 0233.chr.force_encoding('utf-8')],
+      ['"\\x9C"', 0234.chr.force_encoding('utf-8')],
+      ['"\\x9D"', 0235.chr.force_encoding('utf-8')],
+      ['"\\x9E"', 0236.chr.force_encoding('utf-8')],
+      ['"\\x9F"', 0237.chr.force_encoding('utf-8')],
+      ['"\\xA0"', 0240.chr.force_encoding('utf-8')],
+      ['"\\xA1"', 0241.chr.force_encoding('utf-8')],
+      ['"\\xA2"', 0242.chr.force_encoding('utf-8')],
+      ['"\\xA3"', 0243.chr.force_encoding('utf-8')],
+      ['"\\xA4"', 0244.chr.force_encoding('utf-8')],
+      ['"\\xA5"', 0245.chr.force_encoding('utf-8')],
+      ['"\\xA6"', 0246.chr.force_encoding('utf-8')],
+      ['"\\xA7"', 0247.chr.force_encoding('utf-8')],
+      ['"\\xA8"', 0250.chr.force_encoding('utf-8')],
+      ['"\\xA9"', 0251.chr.force_encoding('utf-8')],
+      ['"\\xAA"', 0252.chr.force_encoding('utf-8')],
+      ['"\\xAB"', 0253.chr.force_encoding('utf-8')],
+      ['"\\xAC"', 0254.chr.force_encoding('utf-8')],
+      ['"\\xAD"', 0255.chr.force_encoding('utf-8')],
+      ['"\\xAE"', 0256.chr.force_encoding('utf-8')],
+      ['"\\xAF"', 0257.chr.force_encoding('utf-8')],
+      ['"\\xB0"', 0260.chr.force_encoding('utf-8')],
+      ['"\\xB1"', 0261.chr.force_encoding('utf-8')],
+      ['"\\xB2"', 0262.chr.force_encoding('utf-8')],
+      ['"\\xB3"', 0263.chr.force_encoding('utf-8')],
+      ['"\\xB4"', 0264.chr.force_encoding('utf-8')],
+      ['"\\xB5"', 0265.chr.force_encoding('utf-8')],
+      ['"\\xB6"', 0266.chr.force_encoding('utf-8')],
+      ['"\\xB7"', 0267.chr.force_encoding('utf-8')],
+      ['"\\xB8"', 0270.chr.force_encoding('utf-8')],
+      ['"\\xB9"', 0271.chr.force_encoding('utf-8')],
+      ['"\\xBA"', 0272.chr.force_encoding('utf-8')],
+      ['"\\xBB"', 0273.chr.force_encoding('utf-8')],
+      ['"\\xBC"', 0274.chr.force_encoding('utf-8')],
+      ['"\\xBD"', 0275.chr.force_encoding('utf-8')],
+      ['"\\xBE"', 0276.chr.force_encoding('utf-8')],
+      ['"\\xBF"', 0277.chr.force_encoding('utf-8')],
+      ['"\\xC0"', 0300.chr.force_encoding('utf-8')],
+      ['"\\xC1"', 0301.chr.force_encoding('utf-8')],
+      ['"\\xC2"', 0302.chr.force_encoding('utf-8')],
+      ['"\\xC3"', 0303.chr.force_encoding('utf-8')],
+      ['"\\xC4"', 0304.chr.force_encoding('utf-8')],
+      ['"\\xC5"', 0305.chr.force_encoding('utf-8')],
+      ['"\\xC6"', 0306.chr.force_encoding('utf-8')],
+      ['"\\xC7"', 0307.chr.force_encoding('utf-8')],
+      ['"\\xC8"', 0310.chr.force_encoding('utf-8')],
+      ['"\\xC9"', 0311.chr.force_encoding('utf-8')],
+      ['"\\xCA"', 0312.chr.force_encoding('utf-8')],
+      ['"\\xCB"', 0313.chr.force_encoding('utf-8')],
+      ['"\\xCC"', 0314.chr.force_encoding('utf-8')],
+      ['"\\xCD"', 0315.chr.force_encoding('utf-8')],
+      ['"\\xCE"', 0316.chr.force_encoding('utf-8')],
+      ['"\\xCF"', 0317.chr.force_encoding('utf-8')],
+      ['"\\xD0"', 0320.chr.force_encoding('utf-8')],
+      ['"\\xD1"', 0321.chr.force_encoding('utf-8')],
+      ['"\\xD2"', 0322.chr.force_encoding('utf-8')],
+      ['"\\xD3"', 0323.chr.force_encoding('utf-8')],
+      ['"\\xD4"', 0324.chr.force_encoding('utf-8')],
+      ['"\\xD5"', 0325.chr.force_encoding('utf-8')],
+      ['"\\xD6"', 0326.chr.force_encoding('utf-8')],
+      ['"\\xD7"', 0327.chr.force_encoding('utf-8')],
+      ['"\\xD8"', 0330.chr.force_encoding('utf-8')],
+      ['"\\xD9"', 0331.chr.force_encoding('utf-8')],
+      ['"\\xDA"', 0332.chr.force_encoding('utf-8')],
+      ['"\\xDB"', 0333.chr.force_encoding('utf-8')],
+      ['"\\xDC"', 0334.chr.force_encoding('utf-8')],
+      ['"\\xDD"', 0335.chr.force_encoding('utf-8')],
+      ['"\\xDE"', 0336.chr.force_encoding('utf-8')],
+      ['"\\xDF"', 0337.chr.force_encoding('utf-8')],
+      ['"\\xE0"', 0340.chr.force_encoding('utf-8')],
+      ['"\\xE1"', 0341.chr.force_encoding('utf-8')],
+      ['"\\xE2"', 0342.chr.force_encoding('utf-8')],
+      ['"\\xE3"', 0343.chr.force_encoding('utf-8')],
+      ['"\\xE4"', 0344.chr.force_encoding('utf-8')],
+      ['"\\xE5"', 0345.chr.force_encoding('utf-8')],
+      ['"\\xE6"', 0346.chr.force_encoding('utf-8')],
+      ['"\\xE7"', 0347.chr.force_encoding('utf-8')],
+      ['"\\xE8"', 0350.chr.force_encoding('utf-8')],
+      ['"\\xE9"', 0351.chr.force_encoding('utf-8')],
+      ['"\\xEA"', 0352.chr.force_encoding('utf-8')],
+      ['"\\xEB"', 0353.chr.force_encoding('utf-8')],
+      ['"\\xEC"', 0354.chr.force_encoding('utf-8')],
+      ['"\\xED"', 0355.chr.force_encoding('utf-8')],
+      ['"\\xEE"', 0356.chr.force_encoding('utf-8')],
+      ['"\\xEF"', 0357.chr.force_encoding('utf-8')],
+      ['"\\xF0"', 0360.chr.force_encoding('utf-8')],
+      ['"\\xF1"', 0361.chr.force_encoding('utf-8')],
+      ['"\\xF2"', 0362.chr.force_encoding('utf-8')],
+      ['"\\xF3"', 0363.chr.force_encoding('utf-8')],
+      ['"\\xF4"', 0364.chr.force_encoding('utf-8')],
+      ['"\\xF5"', 0365.chr.force_encoding('utf-8')],
+      ['"\\xF6"', 0366.chr.force_encoding('utf-8')],
+      ['"\\xF7"', 0367.chr.force_encoding('utf-8')],
+      ['"\\xF8"', 0370.chr.force_encoding('utf-8')],
+      ['"\\xF9"', 0371.chr.force_encoding('utf-8')],
+      ['"\\xFA"', 0372.chr.force_encoding('utf-8')],
+      ['"\\xFB"', 0373.chr.force_encoding('utf-8')],
+      ['"\\xFC"', 0374.chr.force_encoding('utf-8')],
+      ['"\\xFD"', 0375.chr.force_encoding('utf-8')],
+      ['"\\xFE"', 0376.chr.force_encoding('utf-8')],
+      ['"\\xFF"', 0377.chr.force_encoding('utf-8')]
+    ].should be_computed_by(:undump)
+  end
 
-    it "returns a string with \\uXXXX notation replaced with multi-byte UTF-8 characters" do
-      [ ['"\u0080"', 0200.chr('utf-8')],
-        ['"\u0081"', 0201.chr('utf-8')],
-        ['"\u0082"', 0202.chr('utf-8')],
-        ['"\u0083"', 0203.chr('utf-8')],
-        ['"\u0084"', 0204.chr('utf-8')],
-        ['"\u0086"', 0206.chr('utf-8')],
-        ['"\u0087"', 0207.chr('utf-8')],
-        ['"\u0088"', 0210.chr('utf-8')],
-        ['"\u0089"', 0211.chr('utf-8')],
-        ['"\u008a"', 0212.chr('utf-8')],
-        ['"\u008b"', 0213.chr('utf-8')],
-        ['"\u008c"', 0214.chr('utf-8')],
-        ['"\u008d"', 0215.chr('utf-8')],
-        ['"\u008e"', 0216.chr('utf-8')],
-        ['"\u008f"', 0217.chr('utf-8')],
-        ['"\u0090"', 0220.chr('utf-8')],
-        ['"\u0091"', 0221.chr('utf-8')],
-        ['"\u0092"', 0222.chr('utf-8')],
-        ['"\u0093"', 0223.chr('utf-8')],
-        ['"\u0094"', 0224.chr('utf-8')],
-        ['"\u0095"', 0225.chr('utf-8')],
-        ['"\u0096"', 0226.chr('utf-8')],
-        ['"\u0097"', 0227.chr('utf-8')],
-        ['"\u0098"', 0230.chr('utf-8')],
-        ['"\u0099"', 0231.chr('utf-8')],
-        ['"\u009a"', 0232.chr('utf-8')],
-        ['"\u009b"', 0233.chr('utf-8')],
-        ['"\u009c"', 0234.chr('utf-8')],
-        ['"\u009d"', 0235.chr('utf-8')],
-        ['"\u009e"', 0236.chr('utf-8')],
-        ['"\u009f"', 0237.chr('utf-8')],
-      ].should be_computed_by(:undump)
-    end
+  it "returns a string with \\u{} notation replaced with multi-byte UTF-8 characters" do
+    [ ['"\u{80}"', 0200.chr('utf-8')],
+      ['"\u{81}"', 0201.chr('utf-8')],
+      ['"\u{82}"', 0202.chr('utf-8')],
+      ['"\u{83}"', 0203.chr('utf-8')],
+      ['"\u{84}"', 0204.chr('utf-8')],
+      ['"\u{86}"', 0206.chr('utf-8')],
+      ['"\u{87}"', 0207.chr('utf-8')],
+      ['"\u{88}"', 0210.chr('utf-8')],
+      ['"\u{89}"', 0211.chr('utf-8')],
+      ['"\u{8a}"', 0212.chr('utf-8')],
+      ['"\u{8b}"', 0213.chr('utf-8')],
+      ['"\u{8c}"', 0214.chr('utf-8')],
+      ['"\u{8d}"', 0215.chr('utf-8')],
+      ['"\u{8e}"', 0216.chr('utf-8')],
+      ['"\u{8f}"', 0217.chr('utf-8')],
+      ['"\u{90}"', 0220.chr('utf-8')],
+      ['"\u{91}"', 0221.chr('utf-8')],
+      ['"\u{92}"', 0222.chr('utf-8')],
+      ['"\u{93}"', 0223.chr('utf-8')],
+      ['"\u{94}"', 0224.chr('utf-8')],
+      ['"\u{95}"', 0225.chr('utf-8')],
+      ['"\u{96}"', 0226.chr('utf-8')],
+      ['"\u{97}"', 0227.chr('utf-8')],
+      ['"\u{98}"', 0230.chr('utf-8')],
+      ['"\u{99}"', 0231.chr('utf-8')],
+      ['"\u{9a}"', 0232.chr('utf-8')],
+      ['"\u{9b}"', 0233.chr('utf-8')],
+      ['"\u{9c}"', 0234.chr('utf-8')],
+      ['"\u{9d}"', 0235.chr('utf-8')],
+      ['"\u{9e}"', 0236.chr('utf-8')],
+      ['"\u{9f}"', 0237.chr('utf-8')],
+    ].should be_computed_by(:undump)
+  end
 
-    it "undumps correctly string produced from non ASCII-compatible one" do
-      s = "\u{876}".encode('utf-16be')
-      s.dump.undump.should == s
+  it "returns a string with \\uXXXX notation replaced with multi-byte UTF-8 characters" do
+    [ ['"\u0080"', 0200.chr('utf-8')],
+      ['"\u0081"', 0201.chr('utf-8')],
+      ['"\u0082"', 0202.chr('utf-8')],
+      ['"\u0083"', 0203.chr('utf-8')],
+      ['"\u0084"', 0204.chr('utf-8')],
+      ['"\u0086"', 0206.chr('utf-8')],
+      ['"\u0087"', 0207.chr('utf-8')],
+      ['"\u0088"', 0210.chr('utf-8')],
+      ['"\u0089"', 0211.chr('utf-8')],
+      ['"\u008a"', 0212.chr('utf-8')],
+      ['"\u008b"', 0213.chr('utf-8')],
+      ['"\u008c"', 0214.chr('utf-8')],
+      ['"\u008d"', 0215.chr('utf-8')],
+      ['"\u008e"', 0216.chr('utf-8')],
+      ['"\u008f"', 0217.chr('utf-8')],
+      ['"\u0090"', 0220.chr('utf-8')],
+      ['"\u0091"', 0221.chr('utf-8')],
+      ['"\u0092"', 0222.chr('utf-8')],
+      ['"\u0093"', 0223.chr('utf-8')],
+      ['"\u0094"', 0224.chr('utf-8')],
+      ['"\u0095"', 0225.chr('utf-8')],
+      ['"\u0096"', 0226.chr('utf-8')],
+      ['"\u0097"', 0227.chr('utf-8')],
+      ['"\u0098"', 0230.chr('utf-8')],
+      ['"\u0099"', 0231.chr('utf-8')],
+      ['"\u009a"', 0232.chr('utf-8')],
+      ['"\u009b"', 0233.chr('utf-8')],
+      ['"\u009c"', 0234.chr('utf-8')],
+      ['"\u009d"', 0235.chr('utf-8')],
+      ['"\u009e"', 0236.chr('utf-8')],
+      ['"\u009f"', 0237.chr('utf-8')],
+    ].should be_computed_by(:undump)
+  end
 
-      '"\\bv".force_encoding("UTF-16BE")'.undump.should == "\u0876".encode('utf-16be')
-    end
+  it "undumps correctly string produced from non ASCII-compatible one" do
+    s = "\u{876}".encode('utf-16be')
+    s.dump.undump.should == s
 
-    it "keeps origin encoding" do
-      '"foo"'.encode("ISO-8859-1").undump.encoding.should == Encoding::ISO_8859_1
-      '"foo"'.encode('windows-1251').undump.encoding.should == Encoding::Windows_1251
-    end
+    '"\\bv".force_encoding("UTF-16BE")'.undump.should == "\u0876".encode('utf-16be')
+  end
+
+  it "keeps origin encoding" do
+    '"foo"'.encode("ISO-8859-1").undump.encoding.should == Encoding::ISO_8859_1
+    '"foo"'.encode('windows-1251').undump.encoding.should == Encoding::Windows_1251
+  end
 
-    describe "Limitations" do
-      it "cannot undump non ASCII-compatible string" do
-        -> { '"foo"'.encode('utf-16le').undump }.should raise_error(Encoding::CompatibilityError)
-      end
+  describe "Limitations" do
+    it "cannot undump non ASCII-compatible string" do
+      -> { '"foo"'.encode('utf-16le').undump }.should raise_error(Encoding::CompatibilityError)
     end
+  end
 
-    describe "invalid dump" do
-      it "raises RuntimeError exception if wrapping \" are missing" do
-        -> { 'foo'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
-        -> { '"foo'.undump }.should raise_error(RuntimeError, /unterminated dumped string/)
-        -> { 'foo"'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
-        -> { "'foo'".undump }.should raise_error(RuntimeError, /invalid dumped string/)
-      end
+  describe "invalid dump" do
+    it "raises RuntimeError exception if wrapping \" are missing" do
+      -> { 'foo'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
+      -> { '"foo'.undump }.should raise_error(RuntimeError, /unterminated dumped string/)
+      -> { 'foo"'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
+      -> { "'foo'".undump }.should raise_error(RuntimeError, /invalid dumped string/)
+    end
 
-      it "raises RuntimeError if there is incorrect \\x sequence" do
-        -> { '"\x"'.undump }.should raise_error(RuntimeError, /invalid hex escape/)
-        -> { '"\\x3y"'.undump }.should raise_error(RuntimeError, /invalid hex escape/)
-      end
+    it "raises RuntimeError if there is incorrect \\x sequence" do
+      -> { '"\x"'.undump }.should raise_error(RuntimeError, /invalid hex escape/)
+      -> { '"\\x3y"'.undump }.should raise_error(RuntimeError, /invalid hex escape/)
+    end
 
-      it "raises RuntimeError in there is incorrect \\u sequence" do
-        -> { '"\\u"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
-        -> { '"\\u{"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
-        -> { '"\\u{3042"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
-        -> { '"\\u"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
-      end
+    it "raises RuntimeError in there is incorrect \\u sequence" do
+      -> { '"\\u"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
+      -> { '"\\u{"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
+      -> { '"\\u{3042"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
+      -> { '"\\u"'.undump }.should raise_error(RuntimeError, /invalid Unicode escape/)
+    end
 
-      it "raises RuntimeError if there is malformed dump of non ASCII-compatible string" do
-        -> { '"".force_encoding("BINARY"'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
-        -> { '"".force_encoding("Unknown")'.undump }.should raise_error(RuntimeError, /dumped string has unknown encoding name/)
-        -> { '"".force_encoding()'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
-      end
+    it "raises RuntimeError if there is malformed dump of non ASCII-compatible string" do
+      -> { '"".force_encoding("BINARY"'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
+      -> { '"".force_encoding("Unknown")'.undump }.should raise_error(RuntimeError, /dumped string has unknown encoding name/)
+      -> { '"".force_encoding()'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
+    end
 
-      it "raises RuntimeError if string contains \0 character" do
-        -> { "\"foo\0\"".undump }.should raise_error(RuntimeError, /string contains null byte/)
-      end
+    it "raises RuntimeError if string contains \0 character" do
+      -> { "\"foo\0\"".undump }.should raise_error(RuntimeError, /string contains null byte/)
+    end
 
-      it "raises RuntimeError if string contains non ASCII character" do
-        -> { "\"\u3042\"".undump }.should raise_error(RuntimeError, /non-ASCII character detected/)
-      end
+    it "raises RuntimeError if string contains non ASCII character" do
+      -> { "\"\u3042\"".undump }.should raise_error(RuntimeError, /non-ASCII character detected/)
+    end
 
-      it "raises RuntimeError if there are some excessive \"" do
-        -> { '" "" "'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
-      end
+    it "raises RuntimeError if there are some excessive \"" do
+      -> { '" "" "'.undump }.should raise_error(RuntimeError, /invalid dumped string/)
     end
   end
 end
diff --git a/spec/ruby/core/struct/hash_spec.rb b/spec/ruby/core/struct/hash_spec.rb
index 5ed4ace489..545929e402 100644
--- a/spec/ruby/core/struct/hash_spec.rb
+++ b/spec/ruby/core/struct/hash_spec.rb
@@ -25,14 +25,12 @@ describe "Struct#hash" do
     s1.hash.should_not == s2.hash
   end
 
-  ruby_version_is "2.5" do
-    it "returns different hashes for structs with different values when using keyword_init: true" do
-      key = :"1 non symbol member"
-      struct_class = Struct.new(key, keyword_init: true)
-      t1 = struct_class.new(key => 1)
-      t2 = struct_class.new(key => 2)
-      t1.hash.should_not == t2.hash
-    end
+  it "returns different hashes for structs with different values when using keyword_init: true" do
+    key = :"1 non symbol member"
+    struct_class = Struct.new(key, keyword_init: true)
+    t1 = struct_class.new(key => 1)
+    t2 = struct_class.new(key => 2)
+    t1.hash.should_not == t2.hash
   end
 
   it "allows for overriding methods in an included module" do
diff --git a/spec/ruby/core/struct/new_spec.rb b/spec/ruby/core/struct/new_spec.rb
index 071aa38d25..bb814e7cd1 100644
--- a/spec/ruby/core/struct/new_spec.rb
+++ b/spec/ruby/core/struct/new_spec.rb
@@ -62,16 +62,8 @@ describe "Struct.new" do
     -> { Struct.new(:animal, ['chris', 'evan'])    }.should raise_error(TypeError)
   end
 
-  ruby_version_is ""..."2.5" do
-    it "raises a TypeError if an argument is a Hash" do
-      -> { Struct.new(:animal, { name: 'chris' }) }.should raise_error(TypeError)
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "raises a ArgumentError if passed a Hash with an unknown key" do
-      -> { Struct.new(:animal, { name: 'chris' }) }.should raise_error(ArgumentError)
-    end
+  it "raises a ArgumentError if passed a Hash with an unknown key" do
+    -> { Struct.new(:animal, { name: 'chris' }) }.should raise_error(ArgumentError)
   end
 
   it "raises ArgumentError when there is a duplicate member" do
@@ -147,71 +139,69 @@ describe "Struct.new" do
     end
   end
 
-  ruby_version_is "2.5" do
-    context "keyword_init: true option" do
-      before :all do
-        @struct_with_kwa = Struct.new(:name, :legs, keyword_init: true)
-      end
+  context "keyword_init: true option" do
+    before :all do
+      @struct_with_kwa = Struct.new(:name, :legs, keyword_init: true)
+    end
+
+    it "creates a class that accepts keyword arguments to initialize" do
+      obj = @struct_with_kwa.new(name: "elefant", legs: 4)
+      obj.name.should == "elefant"
+      obj.legs.should == 4
+    end
+
+    it "raises when there is a duplicate member" do
+      -> { Struct.new(:foo, :foo, keyword_init: true) }.should raise_error(ArgumentError, "duplicate member: foo")
+    end
 
-      it "creates a class that accepts keyword arguments to initialize" do
-        obj = @struct_with_kwa.new(name: "elefant", legs: 4)
+    describe "new class instantiation" do
+      it "accepts arguments as hash as well" do
+        obj = @struct_with_kwa.new({name: "elefant", legs: 4})
         obj.name.should == "elefant"
         obj.legs.should == 4
       end
 
-      it "raises when there is a duplicate member" do
-        -> { Struct.new(:foo, :foo, keyword_init: true) }.should raise_error(ArgumentError, "duplicate member: foo")
+      it "allows missing arguments" do
+        obj = @struct_with_kwa.new(name: "elefant")
+        obj.name.should == "elefant"
+        obj.legs.should be_nil
       end
 
-      describe "new class instantiation" do
-        it "accepts arguments as hash as well" do
-          obj = @struct_with_kwa.new({name: "elefant", legs: 4})
-          obj.name.should == "elefant"
-          obj.legs.should == 4
-        end
-
-        it "allows missing arguments" do
-          obj = @struct_with_kwa.new(name: "elefant")
-          obj.name.should == "elefant"
-          obj.legs.should be_nil
-        end
-
-        it "allows no arguments" do
-          obj = @struct_with_kwa.new
-          obj.name.should be_nil
-          obj.legs.should be_nil
-        end
+      it "allows no arguments" do
+        obj = @struct_with_kwa.new
+        obj.name.should be_nil
+        obj.legs.should be_nil
+      end
 
-        it "raises ArgumentError when passed not declared keyword argument" do
-          -> {
-            @struct_with_kwa.new(name: "elefant", legs: 4, foo: "bar")
-          }.should raise_error(ArgumentError, /unknown keywords: foo/)
-        end
+      it "raises ArgumentError when passed not declared keyword argument" do
+        -> {
+          @struct_with_kwa.new(name: "elefant", legs: 4, foo: "bar")
+        }.should raise_error(ArgumentError, /unknown keywords: foo/)
+      end
 
-        it "raises ArgumentError when passed a list of arguments" do
-          -> {
-            @struct_with_kwa.new("elefant", 4)
-          }.should raise_error(ArgumentError, /wrong number of arguments/)
-        end
+      it "raises ArgumentError when passed a list of arguments" do
+        -> {
+          @struct_with_kwa.new("elefant", 4)
+        }.should raise_error(ArgumentError, /wrong number of arguments/)
+      end
 
-        it "raises ArgumentError when passed a single non-hash argument" do
-          -> {
-            @struct_with_kwa.new("elefant")
-          }.should raise_error(ArgumentError, /wrong number of arguments/)
-        end
+      it "raises ArgumentError when passed a single non-hash argument" do
+        -> {
+          @struct_with_kwa.new("elefant")
+        }.should raise_error(ArgumentError, /wrong number of arguments/)
       end
     end
+  end
 
-    context "keyword_init: false option" do
-      before :all do
-        @struct_without_kwa = Struct.new(:name, :legs, keyword_init: false)
-      end
+  context "keyword_init: false option" do
+    before :all do
+      @struct_without_kwa = Struct.new(:name, :legs, keyword_init: false)
+    end
 
-      it "behaves like it does without :keyword_init option" do
-        obj = @struct_without_kwa.new("elefant", 4)
-        obj.name.should == "elefant"
-        obj.legs.should == 4
-      end
+    it "behaves like it does without :keyword_init option" do
+      obj = @struct_without_kwa.new("elefant", 4)
+      obj.name.should == "elefant"
+      obj.legs.should == 4
     end
   end
 end
diff --git a/spec/ruby/core/thread/fetch_spec.rb b/spec/ruby/core/thread/fetch_spec.rb
index d71c938880..6b37d4cfc5 100644
--- a/spec/ruby/core/thread/fetch_spec.rb
+++ b/spec/ruby/core/thread/fetch_spec.rb
@@ -1,38 +1,36 @@
 require_relative '../../spec_helper'
 
-ruby_version_is '2.5' do
-  describe 'Thread#fetch' do
-    describe 'with 2 arguments' do
-      it 'returns the value of the fiber-local variable if value has been assigned' do
-        th = Thread.new { Thread.current[:cat] = 'meow' }
-        th.join
-        th.fetch(:cat, true).should == 'meow'
-      end
-
-      it "returns the default value if fiber-local variable hasn't been assigned" do
-        th = Thread.new {}
-        th.join
-        th.fetch(:cat, true).should == true
-      end
+describe 'Thread#fetch' do
+  describe 'with 2 arguments' do
+    it 'returns the value of the fiber-local variable if value has been assigned' do
+      th = Thread.new { Thread.current[:cat] = 'meow' }
+      th.join
+      th.fetch(:cat, true).should == 'meow'
     end
 
-    describe 'with 1 argument' do
-      it 'raises a KeyError when the Thread does not have a fiber-local variable of the same name' do
-        th = Thread.new {}
-        th.join
-        -> { th.fetch(:cat) }.should raise_error(KeyError)
-      end
+    it "returns the default value if fiber-local variable hasn't been assigned" do
+      th = Thread.new {}
+      th.join
+      th.fetch(:cat, true).should == true
+    end
+  end
 
-      it 'returns the value of the fiber-local variable if value has been assigned' do
-        th = Thread.new { Thread.current[:cat] = 'meow' }
-        th.join
-        th.fetch(:cat).should == 'meow'
-      end
+  describe 'with 1 argument' do
+    it 'raises a KeyError when the Thread does not have a fiber-local variable of the same name' do
+      th = Thread.new {}
+      th.join
+      -> { th.fetch(:cat) }.should raise_error(KeyError)
     end
 
-    it 'raises an ArgumentError when not passed one or two arguments' do
-      -> { Thread.current.fetch() }.should raise_error(ArgumentError)
-      -> { Thread.current.fetch(1, 2, 3) }.should raise_error(ArgumentError)
+    it 'returns the value of the fiber-local variable if value has been assigned' do
+      th = Thread.new { Thread.current[:cat] = 'meow' }
+      th.join
+      th.fetch(:cat).should == 'meow'
     end
   end
+
+  it 'raises an ArgumentError when not passed one or two arguments' do
+    -> { Thread.current.fetch() }.should raise_error(ArgumentError)
+    -> { Thread.current.fetch(1, 2, 3) }.should raise_error(ArgumentError)
+  end
 end
diff --git a/spec/ruby/core/thread/report_on_exception_spec.rb b/spec/ruby/core/thread/report_on_exception_spec.rb
index a6042ba759..bf50a167df 100644
--- a/spec/ruby/core/thread/report_on_exception_spec.rb
+++ b/spec/ruby/core/thread/report_on_exception_spec.rb
@@ -1,16 +1,8 @@
 require_relative '../../spec_helper'
 
 describe "Thread.report_on_exception" do
-  ruby_version_is "2.4"..."2.5" do
-    it "defaults to false" do
-      ruby_exe("p Thread.report_on_exception").should == "false\n"
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "defaults to true" do
-      ruby_exe("p Thread.report_on_exception").should == "true\n"
-    end
+  it "defaults to true" do
+    ruby_exe("p Thread.report_on_exception").should == "true\n"
   end
 end
 
@@ -33,14 +25,12 @@ describe "Thread.report_on_exception=" do
 end
 
 describe "Thread#report_on_exception" do
-  ruby_version_is "2.5" do
-    it "returns true for the main Thread" do
-      Thread.current.report_on_exception.should == true
-    end
+  it "returns true for the main Thread" do
+    Thread.current.report_on_exception.should == true
+  end
 
-    it "returns true for new Threads" do
-      Thread.new { Thread.current.report_on_exception }.value.should == true
-    end
+  it "returns true for new Threads" do
+    Thread.new { Thread.current.report_on_exception }.value.should == true
   end
 
   it "returns whether the Thread will print a backtrace if it exits with an exception" do
diff --git a/spec/ruby/core/thread/to_s_spec.rb b/spec/ruby/core/thread/to_s_spec.rb
index 85976177dc..cb182a017f 100644
--- a/spec/ruby/core/thread/to_s_spec.rb
+++ b/spec/ruby/core/thread/to_s_spec.rb
@@ -1,8 +1,6 @@
 require_relative '../../spec_helper'
 require_relative 'shared/to_s'
 
-ruby_version_is "2.5" do
-  describe "Thread#to_s" do
-    it_behaves_like :thread_to_s, :to_s
-  end
+describe "Thread#to_s" do
+  it_behaves_like :thread_to_s, :to_s
 end
diff --git a/spec/ruby/core/time/at_spec.rb b/spec/ruby/core/time/at_spec.rb
index 368eeb7fca..28a3d7b34c 100644
--- a/spec/ruby/core/time/at_spec.rb
+++ b/spec/ruby/core/time/at_spec.rb
@@ -144,60 +144,58 @@ describe "Time.at" do
     end
   end
 
-  ruby_version_is "2.5" do
-    describe "passed [Time, Numeric, format]" do
-      context ":nanosecond format" do
-        it "treats second argument as nanoseconds" do
-          Time.at(0, 123456789, :nanosecond).nsec.should == 123456789
-        end
+  describe "passed [Time, Numeric, format]" do
+    context ":nanosecond format" do
+      it "treats second argument as nanoseconds" do
+        Time.at(0, 123456789, :nanosecond).nsec.should == 123456789
       end
+    end
 
-      context ":nsec format" do
-        it "treats second argument as nanoseconds" do
-          Time.at(0, 123456789, :nsec).nsec.should == 123456789
-        end
+    context ":nsec format" do
+      it "treats second argument as nanoseconds" do
+        Time.at(0, 123456789, :nsec).nsec.should == 123456789
       end
+    end
 
-      context ":microsecond format" do
-        it "treats second argument as microseconds" do
-          Time.at(0, 123456, :microsecond).nsec.should == 123456000
-        end
+    context ":microsecond format" do
+      it "treats second argument as microseconds" do
+        Time.at(0, 123456, :microsecond).nsec.should == 123456000
       end
+    end
 
-      context ":usec format" do
-        it "treats second argument as microseconds" do
-          Time.at(0, 123456, :usec).nsec.should == 123456000
-        end
+    context ":usec format" do
+      it "treats second argument as microseconds" do
+        Time.at(0, 123456, :usec).nsec.should == 123456000
       end
+    end
 
-      context ":millisecond format" do
-        it "treats second argument as milliseconds" do
-          Time.at(0, 123, :millisecond).nsec.should == 123000000
-        end
+    context ":millisecond format" do
+      it "treats second argument as milliseconds" do
+        Time.at(0, 123, :millisecond).nsec.should == 123000000
       end
+    end
 
-      context "not supported format" do
-        it "raises ArgumentError" do
-          -> { Time.at(0, 123456, 2) }.should raise_error(ArgumentError)
-          -> { Time.at(0, 123456, nil) }.should raise_error(ArgumentError)
-          -> { Time.at(0, 123456, :invalid) }.should raise_error(ArgumentError)
-        end
-
-        it "does not try to convert format to Symbol with #to_sym" do
-          format = "usec"
-          format.should_not_receive(:to_sym)
-          -> { Time.at(0, 123456, format) }.should raise_error(ArgumentError)
-        end
+    context "not supported format" do
+      it "raises ArgumentError" do
+        -> { Time.at(0, 123456, 2) }.should raise_error(ArgumentError)
+        -> { Time.at(0, 123456, nil) }.should raise_error(ArgumentError)
+        -> { Time.at(0, 123456, :invalid) }.should raise_error(ArgumentError)
       end
 
-      it "supports Float second argument" do
-        Time.at(0, 123456789.500, :nanosecond).nsec.should == 123456789
-        Time.at(0, 123456789.500, :nsec).nsec.should == 123456789
-        Time.at(0, 123456.500, :microsecond).nsec.should == 123456500
-        Time.at(0, 123456.500, :usec).nsec.should == 123456500
-        Time.at(0, 123.500, :millisecond).nsec.should == 123500000
+      it "does not try to convert format to Symbol with #to_sym" do
+        format = "usec"
+        format.should_not_receive(:to_sym)
+        -> { Time.at(0, 123456, format) }.should raise_error(ArgumentError)
       end
     end
+
+    it "supports Float second argument" do
+      Time.at(0, 123456789.500, :nanosecond).nsec.should == 123456789
+      Time.at(0, 123456789.500, :nsec).nsec.should == 123456789
+      Time.at(0, 123456.500, :microsecond).nsec.should == 123456500
+      Time.at(0, 123456.500, :usec).nsec.should == 123456500
+      Time.at(0, 123.500, :millisecond).nsec.should == 123500000
+    end
   end
 
   ruby_version_is "2.6" do
diff --git a/spec/ruby/core/time/shared/now.rb b/spec/ruby/core/time/shared/now.rb
index d8e5ac9d50..80f66a1134 100644
--- a/spec/ruby/core/time/shared/now.rb
+++ b/spec/ruby/core/time/shared/now.rb
@@ -18,18 +18,16 @@ describe :time_now, shared: true do
     end
   end
 
-  guard_not -> { platform_is :windows and ruby_version_is ""..."2.5" } do
-    it "has at least microsecond precision" do
-      times = []
-      10_000.times do
-        times << Time.now.nsec
-      end
-
-      # The clock should not be less accurate than expected (times should
-      # not all be a multiple of the next precision up, assuming precisions
-      # are multiples of ten.)
-      expected = 1_000
-      times.select { |t| t % (expected * 10) == 0  }.size.should_not == times.size
+  it "has at least microsecond precision" do
+    times = []
+    10_000.times do
+      times << Time.now.nsec
     end
+
+    # The clock should not be less accurate than expected (times should
+    # not all be a multiple of the next precision up, assuming precisions
+    # are multiples of ten.)
+    expected = 1_000
+    times.select { |t| t % (expected * 10) == 0  }.size.should_not == times.size
   end
 end
diff --git a/spec/ruby/core/tracepoint/new_spec.rb b/spec/ruby/core/tracepoint/new_spec.rb
index 916d826fdf..991048514c 100644
--- a/spec/ruby/core/tracepoint/new_spec.rb
+++ b/spec/ruby/core/tracepoint/new_spec.rb
@@ -55,10 +55,8 @@ describe 'TracePoint.new' do
     -> { TracePoint.new(o) {}}.should raise_error(TypeError)
   end
 
-  ruby_version_is "2.5" do
-    it 'expects to be called with a block' do
-      -> { TracePoint.new(:line) }.should raise_error(ArgumentError, "must be called with a block")
-    end
+  it 'expects to be called with a block' do
+    -> { TracePoint.new(:line) }.should raise_error(ArgumentError, "must be called with a block")
   end
 
   it "raises a Argument error when the given argument doesn't match an event name" do
diff --git a/spec/ruby/core/warning/warn_spec.rb b/spec/ruby/core/warning/warn_spec.rb
index 7daf6323c3..21424c6c76 100644
--- a/spec/ruby/core/warning/warn_spec.rb
+++ b/spec/ruby/core/warning/warn_spec.rb
@@ -51,16 +51,14 @@ describe "Warning.warn" do
     end
   end
 
-  ruby_version_is "2.5" do
-    it "is called by Kernel.warn" do
-      Warning.should_receive(:warn).with("Chunky bacon!\n")
-      verbose = $VERBOSE
-      $VERBOSE = false
-      begin
-        Kernel.warn("Chunky bacon!")
-      ensure
-        $VERBOSE = verbose
-      end
+  it "is called by Kernel.warn" do
+    Warning.should_receive(:warn).with("Chunky bacon!\n")
+    verbose = $VERBOSE
+    $VERBOSE = false
+    begin
+      Kernel.warn("Chunky bacon!")
+    ensure
+      $VERBOSE = verbose
     end
   end
 end
diff --git a/spec/ruby/language/block_spec.rb b/spec/ruby/language/block_spec.rb
index 99366006b0..8a02f61925 100644
--- a/spec/ruby/language/block_spec.rb
+++ b/spec/ruby/language/block_spec.rb
@@ -317,10 +317,8 @@ describe "A block" do
       @y.s(0) { 1 }.should == 1
     end
 
-    ruby_version_is "2.5" do
-      it "may include a rescue clause" do
-        eval("@y.z do raise ArgumentError; rescue ArgumentError; 7; end").should == 7
-      end
+    it "may include a rescue clause" do
+      eval("@y.z do raise ArgumentError; rescue ArgumentError; 7; end").should == 7
     end
   end
 
@@ -333,10 +331,8 @@ describe "A block" do
       @y.s(0) { || 1 }.should == 1
     end
 
-    ruby_version_is "2.5" do
-      it "may include a rescue clause" do
-        eval('@y.z do || raise ArgumentError; rescue ArgumentError; 7; end').should == 7
-      end
+    it "may include a rescue clause" do
+      eval('@y.z do || raise ArgumentError; rescue ArgumentError; 7; end').should == 7
     end
   end
 
@@ -364,10 +360,8 @@ describe "A block" do
       @y.s([1, 2]) { |a| a }.should == [1, 2]
     end
 
-    ruby_version_is "2.5" do
-      it "may include a rescue clause" do
-        eval('@y.s(1) do |x| raise ArgumentError; rescue ArgumentError; 7; end').should == 7
-      end
+    it "may include a rescue clause" do
+      eval('@y.s(1) do |x| raise ArgumentError; rescue ArgumentError; 7; end').should == 7
     end
   end
 
diff --git a/spec/ruby/language/constants_spec.rb b/spec/ruby/language/constants_spec.rb
index c4cf940cba..95b0dcace9 100644
--- a/spec/ruby/language/constants_spec.rb
+++ b/spec/ruby/language/constants_spec.rb
@@ -425,18 +425,8 @@ end
 
 describe "top-level constant lookup" do
   context "on a class" do
-    ruby_version_is "" ... "2.5" do
-      it "searches Object successfully after searching other scopes" do
-        -> {
-          String::Hash.should == Hash
-        }.should complain(/toplevel constant Hash referenced by/)
-      end
-    end
-
-    ruby_version_is "2.5" do
-      it "does not search Object after searching other scopes" do
-        -> { String::Hash }.should raise_error(NameError)
-      end
+    it "does not search Object after searching other scopes" do
+      -> { String::Hash }.should raise_error(NameError)
     end
   end
 
diff --git a/spec/ruby/language/defined_spec.rb b/spec/ruby/language/defined_spec.rb
index 02c69d27b8..ed61ed3b53 100644
--- a/spec/ruby/language/defined_spec.rb
+++ b/spec/ruby/language/defined_spec.rb
@@ -756,16 +756,8 @@ describe "The defined? keyword for a scoped constant" do
     defined?(DefinedSpecs::String).should be_nil
   end
 
-  ruby_version_is ""..."2.5" do
-    it "returns 'constant' when a constant is defined on top-level but not on the class" do
-      defined?(DefinedSpecs::Basic::String).should == 'constant'
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns nil when a constant is defined on top-level but not on the class" do
-      defined?(DefinedSpecs::Basic::String).should be_nil
-    end
+  it "returns nil when a constant is defined on top-level but not on the class" do
+    defined?(DefinedSpecs::Basic::String).should be_nil
   end
 
   it "returns 'constant' if the scoped-scoped constant is defined" do
diff --git a/spec/ruby/language/ensure_spec.rb b/spec/ruby/language/ensure_spec.rb
index a930bda36b..da2389e993 100644
--- a/spec/ruby/language/ensure_spec.rb
+++ b/spec/ruby/language/ensure_spec.rb
@@ -251,15 +251,14 @@ describe "An ensure block inside {} block" do
   end
 end
 
-ruby_version_is "2.5" do
-  describe "An ensure block inside 'do end' block" do
-    before :each do
-      ScratchPad.record []
-    end
+describe "An ensure block inside 'do end' block" do
+  before :each do
+    ScratchPad.record []
+  end
 
-    it "is executed when an exception is raised in it's corresponding begin block" do
-      -> {
-        eval(<<-ruby).call
+  it "is executed when an exception is raised in it's corresponding begin block" do
+    -> {
+      eval(<<-ruby).call
           lambda do
             ScratchPad << :begin
             raise EnsureSpec::Error
@@ -267,13 +266,13 @@ ruby_version_is "2.5" do
             ScratchPad << :ensure
           end
         ruby
-      }.should raise_error(EnsureSpec::Error)
+    }.should raise_error(EnsureSpec::Error)
 
-      ScratchPad.recorded.should == [:begin, :ensure]
-    end
+    ScratchPad.recorded.should == [:begin, :ensure]
+  end
 
-    it "is executed when an exception is raised and rescued in it's corresponding begin block" do
-      eval(<<-ruby).call
+  it "is executed when an exception is raised and rescued in it's corresponding begin block" do
+    eval(<<-ruby).call
         lambda do
           ScratchPad << :begin
           raise "An exception occurred!"
@@ -284,12 +283,12 @@ ruby_version_is "2.5" do
         end
       ruby
 
-      ScratchPad.recorded.should == [:begin, :rescue, :ensure]
-    end
+    ScratchPad.recorded.should == [:begin, :rescue, :ensure]
+  end
 
-    it "is executed even when a symbol is thrown in it's corresponding begin block" do
-      catch(:symbol) do
-        eval(<<-ruby).call
+  it "is executed even when a symbol is thrown in it's corresponding begin block" do
+    catch(:symbol) do
+      eval(<<-ruby).call
           lambda do
             ScratchPad << :begin
             throw(:symbol)
@@ -299,13 +298,13 @@ ruby_version_is "2.5" do
             ScratchPad << :ensure
           end
         ruby
-      end
-
-      ScratchPad.recorded.should == [:begin, :ensure]
     end
 
-    it "is executed when nothing is raised or thrown in it's corresponding begin block" do
-      eval(<<-ruby).call
+    ScratchPad.recorded.should == [:begin, :ensure]
+  end
+
+  it "is executed when nothing is raised or thrown in it's corresponding begin block" do
+    eval(<<-ruby).call
         lambda do
           ScratchPad << :begin
         rescue
@@ -315,11 +314,11 @@ ruby_version_is "2.5" do
         end
       ruby
 
-      ScratchPad.recorded.should == [:begin, :ensure]
-    end
+    ScratchPad.recorded.should == [:begin, :ensure]
+  end
 
-    it "has no return value" do
-      result = eval(<<-ruby).call
+  it "has no return value" do
+    result = eval(<<-ruby).call
         lambda do
           :begin
         ensure
@@ -327,7 +326,6 @@ ruby_version_is "2.5" do
         end
       ruby
 
-      result.should == :begin
-    end
+    result.should == :begin
   end
 end
diff --git a/spec/ruby/language/lambda_spec.rb b/spec/ruby/language/lambda_spec.rb
index 85abf3b996..3f2cb0310c 100644
--- a/spec/ruby/language/lambda_spec.rb
+++ b/spec/ruby/language/lambda_spec.rb
@@ -351,13 +351,10 @@ describe "A lambda expression 'lambda { ... }'" do
     lambda { lambda }.should raise_error(ArgumentError)
   end
 
-  ruby_version_is "2.5" do
-    it "may include a rescue clause" do
-      eval('lambda do raise ArgumentError; rescue ArgumentError; 7; end').should be_an_instance_of(Proc)
-    end
+  it "may include a rescue clause" do
+    eval('lambda do raise ArgumentError; rescue ArgumentError; 7; end').should be_an_instance_of(Proc)
   end
 
-
   context "with an implicit block" do
     before do
       def meth; lambda; end
diff --git a/spec/ruby/language/rescue_spec.rb b/spec/ruby/language/rescue_spec.rb
index aae16bbefb..aa529328a5 100644
--- a/spec/ruby/language/rescue_spec.rb
+++ b/spec/ruby/language/rescue_spec.rb
@@ -435,9 +435,8 @@ describe "The rescue keyword" do
     }.should raise_error(SyntaxError)
   end
 
-  ruby_version_is "2.5" do
-    it "allows rescue in 'do end' block" do
-      lambda = eval <<-ruby
+  it "allows rescue in 'do end' block" do
+    lambda = eval <<-ruby
         lambda do
           raise SpecificExampleException
         rescue SpecificExampleException
@@ -445,8 +444,7 @@ describe "The rescue keyword" do
         end.call
       ruby
 
-      ScratchPad.recorded.should == [:caught]
-    end
+    ScratchPad.recorded.should == [:caught]
   end
 
   it "allows 'rescue' in method arguments" do
diff --git a/spec/ruby/language/return_spec.rb b/spec/ruby/language/return_spec.rb
index 7eef6d06ca..6b428c3f56 100644
--- a/spec/ruby/language/return_spec.rb
+++ b/spec/ruby/language/return_spec.rb
@@ -250,31 +250,30 @@ describe "The return keyword" do
     end
   end
 
-  ruby_version_is '2.4.2' do
-    describe "at top level" do
-      before :each do
-        @filename = tmp("top_return.rb")
-        ScratchPad.record []
-      end
+  describe "at top level" do
+    before :each do
+      @filename = tmp("top_return.rb")
+      ScratchPad.record []
+    end
 
-      after do
-        rm_r @filename
-      end
+    after do
+      rm_r @filename
+    end
 
-      it "stops file execution" do
-        ruby_exe(<<-END_OF_CODE).should == "before return\n"
+    it "stops file execution" do
+      ruby_exe(<<-END_OF_CODE).should == "before return\n"
           puts "before return"
           return
 
           puts "after return"
         END_OF_CODE
 
-        $?.exitstatus.should == 0
-      end
+      $?.exitstatus.should == 0
+    end
 
-      describe "within if" do
-        it "is allowed" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "within if" do
+      it "is allowed" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before if"
             if true
               return
@@ -283,14 +282,14 @@ describe "The return keyword" do
             ScratchPad << "after if"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before if"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before if"]
       end
+    end
 
-      describe "within while loop" do
-        it "is allowed" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "within while loop" do
+      it "is allowed" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before while"
             while true
               return
@@ -299,14 +298,14 @@ describe "The return keyword" do
             ScratchPad << "after while"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before while"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before while"]
       end
+    end
 
-      describe "within a begin" do
-        it "is allowed in begin block" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "within a begin" do
+      it "is allowed in begin block" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before begin"
             begin
               return
@@ -315,12 +314,12 @@ describe "The return keyword" do
             ScratchPad << "after begin"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before begin"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before begin"]
+      end
 
-        it "is allowed in ensure block" do
-          File.write(@filename, <<-END_OF_CODE)
+      it "is allowed in ensure block" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before begin"
             begin
             ensure
@@ -330,12 +329,12 @@ describe "The return keyword" do
             ScratchPad << "after begin"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before begin"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before begin"]
+      end
 
-        it "is allowed in rescue block" do
-          File.write(@filename, <<-END_OF_CODE)
+      it "is allowed in rescue block" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before begin"
             begin
               raise
@@ -346,12 +345,12 @@ describe "The return keyword" do
             ScratchPad << "after begin"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before begin"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before begin"]
+      end
 
-        it "fires ensure block before returning" do
-          ruby_exe(<<-END_OF_CODE).should == "within ensure\n"
+      it "fires ensure block before returning" do
+        ruby_exe(<<-END_OF_CODE).should == "within ensure\n"
             begin
               return
             ensure
@@ -360,28 +359,10 @@ describe "The return keyword" do
 
             puts "after begin"
           END_OF_CODE
-        end
-
-        ruby_bug "#14061", "2.4"..."2.5" do
-          it "fires ensure block before returning while loads file" do
-            File.write(@filename, <<-END_OF_CODE)
-              ScratchPad << "before begin"
-              begin
-                return
-              ensure
-                ScratchPad << "within ensure"
-              end
-
-              ScratchPad << "after begin"
-            END_OF_CODE
-
-            load @filename
-            ScratchPad.recorded.should == ["before begin", "within ensure"]
-          end
-        end
+      end
 
-        it "swallows exception if returns in ensure block" do
-          File.write(@filename, <<-END_OF_CODE)
+      it "swallows exception if returns in ensure block" do
+        File.write(@filename, <<-END_OF_CODE)
             begin
               raise
             ensure
@@ -390,45 +371,28 @@ describe "The return keyword" do
             end
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before return"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before return"]
       end
+    end
 
-      describe "within a block" do
-        it "is allowed" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "within a block" do
+      it "is allowed" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before call"
             proc { return }.call
 
             ScratchPad << "after call"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before call"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before call"]
       end
+    end
 
-      describe "within a class" do
-        ruby_version_is ""..."2.5" do
-          it "is allowed" do
-            File.write(@filename, <<-END_OF_CODE)
-              class ReturnSpecs::A
-                ScratchPad << "before return"
-                return
-
-                ScratchPad << "after return"
-              end
-            END_OF_CODE
-
-            load @filename
-            ScratchPad.recorded.should == ["before return"]
-          end
-        end
-
-        ruby_version_is "2.5" do
-          it "raises a SyntaxError" do
-            File.write(@filename, <<-END_OF_CODE)
+    describe "within a class" do
+      it "raises a SyntaxError" do
+        File.write(@filename, <<-END_OF_CODE)
               class ReturnSpecs::A
                 ScratchPad << "before return"
                 return
@@ -437,15 +401,14 @@ describe "The return keyword" do
               end
             END_OF_CODE
 
-            -> { load @filename }.should raise_error(SyntaxError)
-          end
-        end
+        -> { load @filename }.should raise_error(SyntaxError)
       end
+    end
 
-      describe "within a block within a class" do
-        ruby_version_is "2.7" do
-          it "is not allowed" do
-            File.write(@filename, <<-END_OF_CODE)
+    describe "within a block within a class" do
+      ruby_version_is "2.7" do
+        it "is not allowed" do
+          File.write(@filename, <<-END_OF_CODE)
               class ReturnSpecs::A
                 ScratchPad << "before return"
                 1.times { return }
@@ -453,57 +416,56 @@ describe "The return keyword" do
               end
             END_OF_CODE
 
-            -> { load @filename }.should raise_error(LocalJumpError)
-          end
+          -> { load @filename }.should raise_error(LocalJumpError)
         end
       end
+    end
 
-      describe "file loading" do
-        it "stops file loading and execution" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "file loading" do
+      it "stops file loading and execution" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before return"
             return
             ScratchPad << "after return"
           END_OF_CODE
 
-          load @filename
-          ScratchPad.recorded.should == ["before return"]
-        end
+        load @filename
+        ScratchPad.recorded.should == ["before return"]
       end
+    end
 
-      describe "file requiring" do
-        it "stops file loading and execution" do
-          File.write(@filename, <<-END_OF_CODE)
+    describe "file requiring" do
+      it "stops file loading and execution" do
+        File.write(@filename, <<-END_OF_CODE)
             ScratchPad << "before return"
             return
             ScratchPad << "after return"
           END_OF_CODE
 
-          require @filename
-          ScratchPad.recorded.should == ["before return"]
-        end
+        require @filename
+        ScratchPad.recorded.should == ["before return"]
       end
+    end
 
-      describe "return with argument" do
-        ruby_version_is ""..."2.7" do
-          it "does not affect exit status" do
-            ruby_exe(<<-END_OF_CODE).should == ""
+    describe "return with argument" do
+      ruby_version_is ""..."2.7" do
+        it "does not affect exit status" do
+          ruby_exe(<<-END_OF_CODE).should == ""
               return 10
             END_OF_CODE
 
-            $?.exitstatus.should == 0
-          end
+          $?.exitstatus.should == 0
         end
+      end
 
-        ruby_version_is "2.7" do
-          it "warns but does not affect exit status" do
-            err = ruby_exe(<<-END_OF_CODE, args: "2>&1")
+      ruby_version_is "2.7" do
+        it "warns but does not affect exit status" do
+          err = ruby_exe(<<-END_OF_CODE, args: "2>&1")
               return 10
             END_OF_CODE
-            $?.exitstatus.should == 0
+          $?.exitstatus.should == 0
 
-            err.should =~ /warning: argument of top-level return is ignored/
-          end
+          err.should =~ /warning: argument of top-level return is ignored/
         end
       end
     end
diff --git a/spec/ruby/library/bigdecimal/constants_spec.rb b/spec/ruby/library/bigdecimal/constants_spec.rb
index 1eb24d85cb..8d879c036a 100644
--- a/spec/ruby/library/bigdecimal/constants_spec.rb
+++ b/spec/ruby/library/bigdecimal/constants_spec.rb
@@ -2,10 +2,8 @@ require_relative '../../spec_helper'
 require 'bigdecimal'
 
 describe "BigDecimal constants" do
-  ruby_version_is "2.5" do
-    it "defines a VERSION value" do
-      BigDecimal.const_defined?(:VERSION).should be_true
-    end
+  it "defines a VERSION value" do
+    BigDecimal.const_defined?(:VERSION).should be_true
   end
 
   it "has a BASE value" do
diff --git a/spec/ruby/library/bigdecimal/shared/clone.rb b/spec/ruby/library/bigdecimal/shared/clone.rb
index e58df3a94b..935ef76e7e 100644
--- a/spec/ruby/library/bigdecimal/shared/clone.rb
+++ b/spec/ruby/library/bigdecimal/shared/clone.rb
@@ -5,20 +5,9 @@ describe :bigdecimal_clone, shared: true do
     @obj = BigDecimal("1.2345")
   end
 
-  ruby_version_is "" ... "2.5" do
-    it "copies the BigDecimal's value to a newly allocated object" do
-      copy = @obj.public_send(@method)
+  it "returns self" do
+    copy = @obj.public_send(@method)
 
-      copy.should_not equal(@obj)
-      copy.should == @obj
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns self" do
-      copy = @obj.public_send(@method)
-
-      copy.should equal(@obj)
-    end
+    copy.should equal(@obj)
   end
 end
diff --git a/spec/ruby/library/cgi/cookie/to_s_spec.rb b/spec/ruby/library/cgi/cookie/to_s_spec.rb
index 978c2d33eb..da15e6ed2a 100644
--- a/spec/ruby/library/cgi/cookie/to_s_spec.rb
+++ b/spec/ruby/library/cgi/cookie/to_s_spec.rb
@@ -27,16 +27,7 @@ describe "CGI::Cookie#to_s" do
     cookie.to_s.should == "test-cookie=+%21%22%23%24%25%26%27%28%29%2A%2B%2C-.%2F0123456789%3A%3B%3C%3D%3E%3F%40ABCDEFGHIJKLMNOPQRSTUVWXYZ%5B%5C%5D%5E_%60abcdefghijklmnopqrstuvwxyz%7B%7C%7D; path="
   end
 
-  ruby_version_is ""..."2.5" do
-    it "escapes tilde" do
-      cookie = CGI::Cookie.new("test-cookie", "~").to_s.should == "test-cookie=%7E; path="
-    end
+  it "does not escape tilde" do
+    cookie = CGI::Cookie.new("test-cookie", "~").to_s.should == "test-cookie=~; path="
   end
-
-  ruby_version_is "2.5" do
-    it "does not escape tilde" do
-      cookie = CGI::Cookie.new("test-cookie", "~").to_s.should == "test-cookie=~; path="
-    end
-  end
-
 end
diff --git a/spec/ruby/library/cgi/escape_spec.rb b/spec/ruby/library/cgi/escape_spec.rb
index 351bfe1070..2f1913970e 100644
--- a/spec/ruby/library/cgi/escape_spec.rb
+++ b/spec/ruby/library/cgi/escape_spec.rb
@@ -12,15 +12,7 @@ describe "CGI.escape" do
     CGI.escape(input).should == expected
   end
 
-  ruby_version_is ""..."2.5" do
-    it "escapes tilde" do
-      CGI.escape("~").should == "%7E"
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not escape tilde" do
-      CGI.escape("~").should == "~"
-    end
+  it "does not escape tilde" do
+    CGI.escape("~").should == "~"
   end
 end
diff --git a/spec/ruby/library/delegate/delegator/eql_spec.rb b/spec/ruby/library/delegate/delegator/eql_spec.rb
index 3170d5727a..34f56f44c9 100644
--- a/spec/ruby/library/delegate/delegator/eql_spec.rb
+++ b/spec/ruby/library/delegate/delegator/eql_spec.rb
@@ -2,45 +2,34 @@ require_relative '../../../spec_helper'
 require_relative '../fixtures/classes'
 
 describe "Delegator#eql?" do
-  ruby_version_is ""..."2.5" do
-    it "is delegated" do
-      base = mock('base')
-      delegator = DelegateSpecs::Delegator.new(base)
-      base.should_receive(:eql?).with(42).and_return(:foo)
-      delegator.eql?(42).should == :foo
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "returns true when compared with same delegator" do
-      base = mock('base')
-      delegator = DelegateSpecs::Delegator.new(base)
+  it "returns true when compared with same delegator" do
+    base = mock('base')
+    delegator = DelegateSpecs::Delegator.new(base)
 
-      delegator.eql?(delegator).should be_true
-    end
+    delegator.eql?(delegator).should be_true
+  end
 
-    it "returns true when compared with the inner object" do
-      base = mock('base')
-      delegator = DelegateSpecs::Delegator.new(base)
+  it "returns true when compared with the inner object" do
+    base = mock('base')
+    delegator = DelegateSpecs::Delegator.new(base)
 
-      delegator.eql?(base).should be_true
-    end
+    delegator.eql?(base).should be_true
+  end
 
-    it "returns false when compared with the delegator with other object" do
-      base = mock('base')
-      other = mock('other')
-      delegator0 = DelegateSpecs::Delegator.new(base)
-      delegator1 = DelegateSpecs::Delegator.new(other)
+  it "returns false when compared with the delegator with other object" do
+    base = mock('base')
+    other = mock('other')
+    delegator0 = DelegateSpecs::Delegator.new(base)
+    delegator1 = DelegateSpecs::Delegator.new(other)
 
-      delegator0.eql?(delegator1).should be_false
-    end
+    delegator0.eql?(delegator1).should be_false
+  end
 
-    it "returns false when compared with the other object" do
-      base = mock('base')
-      other = mock('other')
-      delegator = DelegateSpecs::Delegator.new(base)
+  it "returns false when compared with the other object" do
+    base = mock('base')
+    other = mock('other')
+    delegator = DelegateSpecs::Delegator.new(base)
 
-      delegator.eql?(other).should be_false
-    end
+    delegator.eql?(other).should be_false
   end
 end
diff --git a/spec/ruby/library/erb/util/shared/url_encode.rb b/spec/ruby/library/erb/util/shared/url_encode.rb
index 5ac6215523..a2d648fd31 100644
--- a/spec/ruby/library/erb/util/shared/url_encode.rb
+++ b/spec/ruby/library/erb/util/shared/url_encode.rb
@@ -6,16 +6,8 @@ describe :erb_util_url_encode, shared: true do
     ERB::Util.__send__(@method, input).should == expected
   end
 
-  ruby_version_is ""..."2.5" do
-    it "escapes tilde" do
-      ERB::Util.__send__(@method, "~").should == "%7E"
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not escape tilde" do
-      ERB::Util.__send__(@method, "~").should == "~"
-    end
+  it "does not escape tilde" do
+    ERB::Util.__send__(@method, "~").should == "~"
   end
 
   it "encode unicode string" do
diff --git a/spec/ruby/library/getoptlong/shared/get.rb b/spec/ruby/library/getoptlong/shared/get.rb
index 772a7f6773..f44cf583d2 100644
--- a/spec/ruby/library/getoptlong/shared/get.rb
+++ b/spec/ruby/library/getoptlong/shared/get.rb
@@ -53,12 +53,10 @@ describe :getoptlong_get, shared: true do
     end
   end
 
-  ruby_version_is "2.5" do
-    # https://bugs.ruby-lang.org/issues/13858
-    it "returns multiline argument" do
-      argv [ "--size=\n10k\n" ] do
-        @opts.send(@method).should == [ "--size", "\n10k\n" ]
-      end
+  # https://bugs.ruby-lang.org/issues/13858
+  it "returns multiline argument" do
+    argv [ "--size=\n10k\n" ] do
+      @opts.send(@method).should == [ "--size", "\n10k\n" ]
     end
   end
 end
diff --git a/spec/ruby/library/mathn/bignum/exponent_spec.rb b/spec/ruby/library/mathn/bignum/exponent_spec.rb
deleted file mode 100644
index ddd19ffdb4..0000000000
--- a/spec/ruby/library/mathn/bignum/exponent_spec.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Bignum#**" do
-    before :each do
-      @bignum = bignum_value(47)
-    end
-
-    it "returns self raised to other (positive) power" do
-      (@bignum ** 4).should == 7237005577332262361485077344629993318496048279512298547155833600056910050625
-      (@bignum ** 1.2).should be_close(57262152889751597425762.57804, TOLERANCE)
-    end
-
-    it "returns a complex number when negative and raised to a fractional power" do
-      ((-@bignum) ** (1/3)).should be_close(Complex(1048576,1816186.907597341), TOLERANCE)
-      ((-@bignum) ** (1.0/3)).should be_close(Complex(1048576,1816186.907597341), TOLERANCE)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/complex/Complex_spec.rb b/spec/ruby/library/mathn/complex/Complex_spec.rb
deleted file mode 100644
index 105902ed5d..0000000000
--- a/spec/ruby/library/mathn/complex/Complex_spec.rb
+++ /dev/null
@@ -1,14 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Kernel#Complex" do
-    it "returns an Integer if imaginary part is 0" do
-      Complex(42,0).should == 42
-      Complex(42,0).should be_kind_of(Fixnum)
-      Complex(bignum_value,0).should == bignum_value
-      Complex(bignum_value,0).should be_kind_of(Bignum)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/fixnum/exponent_spec.rb b/spec/ruby/library/mathn/fixnum/exponent_spec.rb
deleted file mode 100644
index 160bf7f115..0000000000
--- a/spec/ruby/library/mathn/fixnum/exponent_spec.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Fixnum#**" do
-    it "returns self raised to other (positive) power" do
-      (2 ** 4).should == 16
-      (2 ** 1.2).should be_close(2.2973967, TOLERANCE)
-    end
-
-    it "returns a complex number when negative and raised to a fractional power" do
-      ((-8) ** (1/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
-      ((-8) ** (1.0/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/float/exponent_spec.rb b/spec/ruby/library/mathn/float/exponent_spec.rb
deleted file mode 100644
index 312119db00..0000000000
--- a/spec/ruby/library/mathn/float/exponent_spec.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Float#**" do
-    it "returns self raised to other (positive) power" do
-      (2.0 ** 4).should == 16.0
-      (2.0 ** 1.2).should be_close(2.2973967, TOLERANCE)
-    end
-
-    it "returns a complex number when negative and raised to a fractional power" do
-      ((-8.0) ** (1/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
-      ((-8.0) ** (1.0/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/integer/from_prime_division_spec.rb b/spec/ruby/library/mathn/integer/from_prime_division_spec.rb
deleted file mode 100644
index df2db6d8c1..0000000000
--- a/spec/ruby/library/mathn/integer/from_prime_division_spec.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Integer.from_prime_division" do
-    it "reverses a prime factorization of an integer" do
-      Integer.from_prime_division([[2, 1], [3, 2], [7, 1]]).should == 126
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/integer/prime_division_spec.rb b/spec/ruby/library/mathn/integer/prime_division_spec.rb
deleted file mode 100644
index fb4a1c3fea..0000000000
--- a/spec/ruby/library/mathn/integer/prime_division_spec.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Integer#prime_division" do
-    it "performs a prime factorization of a positive integer" do
-      100.prime_division.should == [[2, 2], [5, 2]]
-    end
-
-    # Proper handling of negative integers has been added to MRI trunk
-    # in revision 24091. Prior to that, all versions of MRI returned nonsense.
-    it "performs a prime factorization of a negative integer" do
-      -26.prime_division.should == [[-1, 1], [2, 1], [13, 1]]
-    end
-
-    it "raises a ZeroDivisionError when is called on zero" do
-      -> { 0.prime_division }.should raise_error(ZeroDivisionError)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/math/fixtures/classes.rb b/spec/ruby/library/mathn/math/fixtures/classes.rb
deleted file mode 100644
index 024732fa7a..0000000000
--- a/spec/ruby/library/mathn/math/fixtures/classes.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-class IncludesMath
-  include Math
-end
diff --git a/spec/ruby/library/mathn/math/rsqrt_spec.rb b/spec/ruby/library/mathn/math/rsqrt_spec.rb
deleted file mode 100644
index 6cb7595afe..0000000000
--- a/spec/ruby/library/mathn/math/rsqrt_spec.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require_relative 'shared/rsqrt'
-
-  describe "Math#rsqrt" do
-    it_behaves_like :mathn_math_rsqrt, :_, IncludesMath.new
-
-    it "is a private instance method" do
-      IncludesMath.should have_private_instance_method(:rsqrt)
-    end
-  end
-
-  describe "Math.rsqrt" do
-    it_behaves_like :mathn_math_rsqrt, :_, Math
-  end
-end
diff --git a/spec/ruby/library/mathn/math/shared/rsqrt.rb b/spec/ruby/library/mathn/math/shared/rsqrt.rb
deleted file mode 100644
index ea3d1b0cfc..0000000000
--- a/spec/ruby/library/mathn/math/shared/rsqrt.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require 'mathn'
-require_relative '../fixtures/classes'
-
-describe :mathn_math_rsqrt, shared: true do
-  it "returns the square root for Rational numbers" do
-    @object.send(:rsqrt, Rational(9, 25)).should == Rational(3, 5)
-    @object.send(:rsqrt, 16/64).should == Rational(1, 2)
-  end
-
-  it "returns the square root for positive numbers" do
-    @object.send(:rsqrt, 1).should == 1
-    @object.send(:rsqrt, 4.0).should == 2.0
-    @object.send(:rsqrt, 12.34).should == Math.sqrt!(12.34)
-  end
-
-  it "raises an Math::DomainError if the argument is a negative number" do
-    -> { @object.send(:rsqrt, -1) }.should raise_error(Math::DomainError)
-    -> { @object.send(:rsqrt, -4.0) }.should raise_error(Math::DomainError)
-    -> { @object.send(:rsqrt, -16/64) }.should raise_error(Math::DomainError)
-  end
-end
diff --git a/spec/ruby/library/mathn/math/shared/sqrt.rb b/spec/ruby/library/mathn/math/shared/sqrt.rb
deleted file mode 100644
index 5e6dae1d4f..0000000000
--- a/spec/ruby/library/mathn/math/shared/sqrt.rb
+++ /dev/null
@@ -1,25 +0,0 @@
-require 'mathn'
-require_relative '../fixtures/classes'
-
-describe :mathn_math_sqrt, shared: true do
-  it "returns the square root for Rational numbers" do
-    @object.send(:sqrt, Rational(9, 25)).should == Rational(3, 5)
-    @object.send(:sqrt, 16/64).should == Rational(1, 2)
-  end
-
-  it "returns the square root for Complex numbers" do
-    @object.send(:sqrt, Complex(1, 0)).should == 1
-  end
-
-  it "returns the square root for positive numbers" do
-    @object.send(:sqrt, 1).should == 1
-    @object.send(:sqrt, 4.0).should == 2.0
-    @object.send(:sqrt, 12.34).should == Math.sqrt!(12.34)
-  end
-
-  it "returns the square root for negative numbers" do
-    @object.send(:sqrt, -9).should == Complex(0, 3)
-    @object.send(:sqrt, -5.29).should == Complex(0, 2.3)
-    @object.send(:sqrt, -16/64).should == Complex(0, 1/2)
-  end
-end
diff --git a/spec/ruby/library/mathn/math/sqrt_spec.rb b/spec/ruby/library/mathn/math/sqrt_spec.rb
deleted file mode 100644
index 49cfe3600e..0000000000
--- a/spec/ruby/library/mathn/math/sqrt_spec.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require_relative 'shared/sqrt'
-
-  describe "Math#rsqrt" do
-    it_behaves_like :mathn_math_sqrt, :_, IncludesMath.new
-
-    it "is a private instance method" do
-      IncludesMath.should have_private_instance_method(:sqrt)
-    end
-  end
-
-  describe "Math.rsqrt" do
-    it_behaves_like :mathn_math_sqrt, :_, Math
-  end
-end
diff --git a/spec/ruby/library/mathn/mathn_spec.rb b/spec/ruby/library/mathn/mathn_spec.rb
deleted file mode 100644
index 129c8f3288..0000000000
--- a/spec/ruby/library/mathn/mathn_spec.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require_relative '../../spec_helper'
-
-describe "mathn" do
-  ruby_version_is "2.5" do
-    it "is no longer part of the standard library" do
-      -> {
-        require "mathn"
-      }.should raise_error(LoadError) { |e|
-        e.path.should == 'mathn'
-      }
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/rational/Rational_spec.rb b/spec/ruby/library/mathn/rational/Rational_spec.rb
deleted file mode 100644
index 9a34c99751..0000000000
--- a/spec/ruby/library/mathn/rational/Rational_spec.rb
+++ /dev/null
@@ -1,14 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Kernel#Rational" do
-    it "returns an Integer if denominator divides numerator evenly" do
-      Rational(42,6).should == 7
-      Rational(42,6).should be_kind_of(Fixnum)
-      Rational(bignum_value,1).should == bignum_value
-      Rational(bignum_value,1).should be_kind_of(Bignum)
-    end
-  end
-end
diff --git a/spec/ruby/library/mathn/rational/inspect_spec.rb b/spec/ruby/library/mathn/rational/inspect_spec.rb
deleted file mode 100644
index cbf67ec0f3..0000000000
--- a/spec/ruby/library/mathn/rational/inspect_spec.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require_relative '../../../spec_helper'
-
-ruby_version_is ''...'2.5' do
-  require 'mathn'
-
-  describe "Rational#inspect" do
-    it "returns a string representation of self" do
-      Rational(3, 4).inspect.should == "(3/4)"
-      Rational(-5, 8).inspect.should == "(-5/8)"
-      Rational(-1, -2).inspect.should == "(1/2)"
-      Rational(0, 2).inspect.should == "0"
-      Rational(bignum_value, 1).inspect.should == "#{bignum_value}"
-    end
-  end
-end
diff --git a/spec/ruby/library/net/ftp/initialize_spec.rb b/spec/ruby/library/net/ftp/initialize_spec.rb
index 507320e494..a2f64ddb1b 100644
--- a/spec/ruby/library/net/ftp/initialize_spec.rb
+++ b/spec/ruby/library/net/ftp/initialize_spec.rb
@@ -6,9 +6,7 @@ describe "Net::FTP#initialize" do
     @ftp = Net::FTP.allocate
     @ftp.stub!(:connect)
     @port_args = []
-    ruby_version_is "2.5" do
-      @port_args << 21
-    end
+    @port_args << 21
   end
 
   it "is private" do
diff --git a/spec/ruby/library/rbconfig/sizeof/limits_spec.rb b/spec/ruby/library/rbconfig/sizeof/limits_spec.rb
index a026135eee..776099da27 100644
--- a/spec/ruby/library/rbconfig/sizeof/limits_spec.rb
+++ b/spec/ruby/library/rbconfig/sizeof/limits_spec.rb
@@ -1,42 +1,40 @@
 require_relative '../../../spec_helper'
 require 'rbconfig/sizeof'
 
-ruby_version_is "2.5" do
-  describe "RbConfig::LIMITS" do
-    it "is a Hash" do
-      RbConfig::LIMITS.should be_kind_of(Hash)
-    end
+describe "RbConfig::LIMITS" do
+  it "is a Hash" do
+    RbConfig::LIMITS.should be_kind_of(Hash)
+  end
 
-    it "has string keys and numeric values" do
-      RbConfig::LIMITS.each do |key, value|
-        key.should be_kind_of String
-        value.should be_kind_of Numeric
-      end
+  it "has string keys and numeric values" do
+    RbConfig::LIMITS.each do |key, value|
+      key.should be_kind_of String
+      value.should be_kind_of Numeric
     end
+  end
 
-    it "contains FIXNUM_MIN and FIXNUM_MAX" do
-      RbConfig::LIMITS["FIXNUM_MIN"].should < 0
-      RbConfig::LIMITS["FIXNUM_MAX"].should > 0
-    end
+  it "contains FIXNUM_MIN and FIXNUM_MAX" do
+    RbConfig::LIMITS["FIXNUM_MIN"].should < 0
+    RbConfig::LIMITS["FIXNUM_MAX"].should > 0
+  end
 
-    it "contains CHAR_MIN and CHAR_MAX" do
-      RbConfig::LIMITS["CHAR_MIN"].should <= 0
-      RbConfig::LIMITS["CHAR_MAX"].should > 0
-    end
+  it "contains CHAR_MIN and CHAR_MAX" do
+    RbConfig::LIMITS["CHAR_MIN"].should <= 0
+    RbConfig::LIMITS["CHAR_MAX"].should > 0
+  end
 
-    it "contains SHRT_MIN and SHRT_MAX" do
-      RbConfig::LIMITS["SHRT_MIN"].should == -32768
-      RbConfig::LIMITS["SHRT_MAX"].should == 32767
-    end
+  it "contains SHRT_MIN and SHRT_MAX" do
+    RbConfig::LIMITS["SHRT_MIN"].should == -32768
+    RbConfig::LIMITS["SHRT_MAX"].should == 32767
+  end
 
-    it "contains INT_MIN and INT_MAX" do
-      RbConfig::LIMITS["INT_MIN"].should < 0
-      RbConfig::LIMITS["INT_MAX"].should > 0
-    end
+  it "contains INT_MIN and INT_MAX" do
+    RbConfig::LIMITS["INT_MIN"].should < 0
+    RbConfig::LIMITS["INT_MAX"].should > 0
+  end
 
-    it "contains LONG_MIN and LONG_MAX" do
-      RbConfig::LIMITS["LONG_MIN"].should < 0
-      RbConfig::LIMITS["LONG_MAX"].should > 0
-    end
+  it "contains LONG_MIN and LONG_MAX" do
+    RbConfig::LIMITS["LONG_MIN"].should < 0
+    RbConfig::LIMITS["LONG_MAX"].should > 0
   end
 end
diff --git a/spec/ruby/library/rbconfig/unicode_version_spec.rb b/spec/ruby/library/rbconfig/unicode_version_spec.rb
index 44216700c8..65bd70c242 100644
--- a/spec/ruby/library/rbconfig/unicode_version_spec.rb
+++ b/spec/ruby/library/rbconfig/unicode_version_spec.rb
@@ -2,12 +2,6 @@ require_relative '../../spec_helper'
 require 'rbconfig'
 
 describe "RbConfig::CONFIG['UNICODE_VERSION']" do
-  ruby_version_is ""..."2.5" do
-    it "is 9.0.0 for Ruby 2.4" do
-      RbConfig::CONFIG['UNICODE_VERSION'].should == "9.0.0"
-    end
-  end
-
   ruby_version_is "2.5"..."2.6" do
     it "is 10.0.0 for Ruby 2.5" do
       RbConfig::CONFIG['UNICODE_VERSION'].should == "10.0.0"
diff --git a/spec/ruby/library/set/case_compare_spec.rb b/spec/ruby/library/set/case_compare_spec.rb
index 193006dbda..70d392a27d 100644
--- a/spec/ruby/library/set/case_compare_spec.rb
+++ b/spec/ruby/library/set/case_compare_spec.rb
@@ -2,13 +2,11 @@ require_relative '../../spec_helper'
 require_relative 'shared/include'
 require 'set'
 
-ruby_version_is "2.5" do
-  describe "Set#===" do
-    it_behaves_like :set_include, :===
+describe "Set#===" do
+  it_behaves_like :set_include, :===
 
-    it "is an alias for include?" do
-      set = Set.new
-      set.method(:===).should == set.method(:include?)
-    end
+  it "is an alias for include?" do
+    set = Set.new
+    set.method(:===).should == set.method(:include?)
   end
 end
diff --git a/spec/ruby/library/set/case_equality_spec.rb b/spec/ruby/library/set/case_equality_spec.rb
index 875630612e..10cbfd380a 100644
--- a/spec/ruby/library/set/case_equality_spec.rb
+++ b/spec/ruby/library/set/case_equality_spec.rb
@@ -2,8 +2,6 @@ require_relative '../../spec_helper'
 require_relative 'shared/include'
 require 'set'
 
-ruby_version_is "2.5" do
-  describe "Set#===" do
-    it_behaves_like :set_include, :===
-  end
+describe "Set#===" do
+  it_behaves_like :set_include, :===
 end
diff --git a/spec/ruby/library/set/sortedset/case_equality_spec.rb b/spec/ruby/library/set/sortedset/case_equality_spec.rb
index 5627917677..48e3735c8e 100644
--- a/spec/ruby/library/set/sortedset/case_equality_spec.rb
+++ b/spec/ruby/library/set/sortedset/case_equality_spec.rb
@@ -2,8 +2,6 @@ require_relative '../../../spec_helper'
 require_relative 'shared/include'
 require 'set'
 
-ruby_version_is "2.5" do
-  describe "SortedSet#===" do
-    it_behaves_like :sorted_set_include, :===
-  end
+describe "SortedSet#===" do
+  it_behaves_like :sorted_set_include, :===
 end
diff --git a/spec/ruby/library/set/to_s_spec.rb b/spec/ruby/library/set/to_s_spec.rb
index ca2806d669..7b9f7b6603 100644
--- a/spec/ruby/library/set/to_s_spec.rb
+++ b/spec/ruby/library/set/to_s_spec.rb
@@ -1,13 +1,11 @@
 require_relative 'shared/inspect'
 require 'set'
 
-ruby_version_is "2.5" do
-  describe "Set#to_s" do
-    it_behaves_like :set_inspect, :to_s
+describe "Set#to_s" do
+  it_behaves_like :set_inspect, :to_s
 
-    it "is an alias of inspect" do
-      set = Set.new
-      set.method(:to_s).should == set.method(:inspect)
-    end
+  it "is an alias of inspect" do
+    set = Set.new
+    set.method(:to_s).should == set.method(:inspect)
   end
 end
diff --git a/spec/ruby/library/socket/basicsocket/read_nonblock_spec.rb b/spec/ruby/library/socket/basicsocket/read_nonblock_spec.rb
index 1823f3d75d..4986fffbc5 100644
--- a/spec/ruby/library/socket/basicsocket/read_nonblock_spec.rb
+++ b/spec/ruby/library/socket/basicsocket/read_nonblock_spec.rb
@@ -1,45 +1,43 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-ruby_version_is "2.5" do
-  describe "BasicSocket#read_nonblock" do
-    SocketSpecs.each_ip_protocol do |family, ip_address|
-      before :each do
-        @r = Socket.new(family, :DGRAM)
-        @w = Socket.new(family, :DGRAM)
+describe "BasicSocket#read_nonblock" do
+  SocketSpecs.each_ip_protocol do |family, ip_address|
+    before :each do
+      @r = Socket.new(family, :DGRAM)
+      @w = Socket.new(family, :DGRAM)
 
-        @r.bind(Socket.pack_sockaddr_in(0, ip_address))
-        @w.send("aaa", 0, @r.getsockname)
-      end
+      @r.bind(Socket.pack_sockaddr_in(0, ip_address))
+      @w.send("aaa", 0, @r.getsockname)
+    end
 
-      after :each do
-        @r.close unless @r.closed?
-        @w.close unless @w.closed?
-      end
+    after :each do
+      @r.close unless @r.closed?
+      @w.close unless @w.closed?
+    end
 
-      it "receives data after it's ready" do
-        IO.select([@r], nil, nil, 2)
-        @r.recv_nonblock(5).should == "aaa"
-      end
+    it "receives data after it's ready" do
+      IO.select([@r], nil, nil, 2)
+      @r.recv_nonblock(5).should == "aaa"
+    end
 
-      platform_is :linux do
-        it 'does not set the IO in nonblock mode' do
-          require 'io/nonblock'
-          @r.nonblock?.should == false
-          IO.select([@r], nil, nil, 2)
-          @r.read_nonblock(3).should == "aaa"
-          @r.nonblock?.should == false
-        end
+    platform_is :linux do
+      it 'does not set the IO in nonblock mode' do
+        require 'io/nonblock'
+        @r.nonblock?.should == false
+        IO.select([@r], nil, nil, 2)
+        @r.read_nonblock(3).should == "aaa"
+        @r.nonblock?.should == false
       end
+    end
 
-      platform_is_not :linux, :windows do
-        it 'sets the IO in nonblock mode' do
-          require 'io/nonblock'
-          @r.nonblock?.should == false
-          IO.select([@r], nil, nil, 2)
-          @r.read_nonblock(3).should == "aaa"
-          @r.nonblock?.should == true
-        end
+    platform_is_not :linux, :windows do
+      it 'sets the IO in nonblock mode' do
+        require 'io/nonblock'
+        @r.nonblock?.should == false
+        IO.select([@r], nil, nil, 2)
+        @r.read_nonblock(3).should == "aaa"
+        @r.nonblock?.should == true
       end
     end
   end
diff --git a/spec/ruby/library/socket/basicsocket/write_nonblock_spec.rb b/spec/ruby/library/socket/basicsocket/write_nonblock_spec.rb
index f2e7366eb1..95ec08a6c7 100644
--- a/spec/ruby/library/socket/basicsocket/write_nonblock_spec.rb
+++ b/spec/ruby/library/socket/basicsocket/write_nonblock_spec.rb
@@ -1,44 +1,42 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-ruby_version_is "2.5" do
-  describe "BasicSocket#write_nonblock" do
-    SocketSpecs.each_ip_protocol do |family, ip_address|
-      before :each do
-        @r = Socket.new(family, :DGRAM)
-        @w = Socket.new(family, :DGRAM)
+describe "BasicSocket#write_nonblock" do
+  SocketSpecs.each_ip_protocol do |family, ip_address|
+    before :each do
+      @r = Socket.new(family, :DGRAM)
+      @w = Socket.new(family, :DGRAM)
 
-        @r.bind(Socket.pack_sockaddr_in(0, ip_address))
-        @w.connect(@r.getsockname)
-      end
+      @r.bind(Socket.pack_sockaddr_in(0, ip_address))
+      @w.connect(@r.getsockname)
+    end
 
-      after :each do
-        @r.close unless @r.closed?
-        @w.close unless @w.closed?
-      end
+    after :each do
+      @r.close unless @r.closed?
+      @w.close unless @w.closed?
+    end
 
-      it "sends data" do
-        @w.write_nonblock("aaa").should == 3
-        IO.select([@r], nil, nil, 2)
-        @r.recv_nonblock(5).should == "aaa"
-      end
+    it "sends data" do
+      @w.write_nonblock("aaa").should == 3
+      IO.select([@r], nil, nil, 2)
+      @r.recv_nonblock(5).should == "aaa"
+    end
 
-      platform_is :linux do
-        it 'does not set the IO in nonblock mode' do
-          require 'io/nonblock'
-          @w.nonblock?.should == false
-          @w.write_nonblock("aaa").should == 3
-          @w.nonblock?.should == false
-        end
+    platform_is :linux do
+      it 'does not set the IO in nonblock mode' do
+        require 'io/nonblock'
+        @w.nonblock?.should == false
+        @w.write_nonblock("aaa").should == 3
+        @w.nonblock?.should == false
       end
+    end
 
-      platform_is_not :linux, :windows do
-        it 'sets the IO in nonblock mode' do
-          require 'io/nonblock'
-          @w.nonblock?.should == false
-          @w.write_nonblock("aaa").should == 3
-          @w.nonblock?.should == true
-        end
+    platform_is_not :linux, :windows do
+      it 'sets the IO in nonblock mode' do
+        require 'io/nonblock'
+        @w.nonblock?.should == false
+        @w.write_nonblock("aaa").should == 3
+        @w.nonblock?.should == true
       end
     end
   end
diff --git a/spec/ruby/library/socket/udpsocket/inspect_spec.rb b/spec/ruby/library/socket/udpsocket/inspect_spec.rb
index 201e8b3fc6..e212120b14 100644
--- a/spec/ruby/library/socket/udpsocket/inspect_spec.rb
+++ b/spec/ruby/library/socket/udpsocket/inspect_spec.rb
@@ -10,16 +10,8 @@ describe 'UDPSocket#inspect' do
     @socket.close
   end
 
-  ruby_version_is ""..."2.5" do
-    it 'returns a String with the fd' do
-      @socket.inspect.should == "#<UDPSocket:fd #{@socket.fileno}>"
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it 'returns a String with the fd, family, address and port' do
-      port = @socket.addr[1]
-      @socket.inspect.should == "#<UDPSocket:fd #{@socket.fileno}, AF_INET, 127.0.0.1, #{port}>"
-    end
+  it 'returns a String with the fd, family, address and port' do
+    port = @socket.addr[1]
+    @socket.inspect.should == "#<UDPSocket:fd #{@socket.fileno}, AF_INET, 127.0.0.1, #{port}>"
   end
 end
diff --git a/spec/ruby/library/yaml/load_documents_spec.rb b/spec/ruby/library/yaml/load_documents_spec.rb
deleted file mode 100644
index 27edbcaa86..0000000000
--- a/spec/ruby/library/yaml/load_documents_spec.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require_relative '../../spec_helper'
-require_relative 'fixtures/common'
-require_relative 'fixtures/strings'
-require_relative 'shared/each_document'
-
-ruby_version_is ''...'2.5' do
-  describe "YAML.load_documents" do
-    it_behaves_like :yaml_each_document, :load_documents
-  end
-end
diff --git a/spec/ruby/library/yaml/tagurize_spec.rb b/spec/ruby/library/yaml/tagurize_spec.rb
deleted file mode 100644
index cc1b757ce9..0000000000
--- a/spec/ruby/library/yaml/tagurize_spec.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require_relative '../../spec_helper'
-require_relative 'fixtures/common'
-
-ruby_version_is ''...'2.5' do
-  describe "YAML.tagurize" do
-    it "converts a type_id to a taguri" do
-      YAML.tagurize('wtf').should == "tag:yaml.org,2002:wtf"
-      YAML.tagurize(1).should == 1
-    end
-  end
-end
diff --git a/spec/ruby/optional/capi/constants_spec.rb b/spec/ruby/optional/capi/constants_spec.rb
index 3d7f0cebd6..172d10a788 100644
--- a/spec/ruby/optional/capi/constants_spec.rb
+++ b/spec/ruby/optional/capi/constants_spec.rb
@@ -31,12 +31,6 @@ describe "C-API constant" do
     @s.rb_mComparable.should == Comparable
   end
 
-  ruby_version_is ""..."2.5" do
-    specify "rb_cData references the Data class" do
-      @s.rb_cData.should == Data
-    end
-  end
-
   specify "rb_cDir references the Dir class" do
     @s.rb_cDir.should == Dir
   end
@@ -89,11 +83,8 @@ describe "C-API constant" do
     @s.rb_mKernel.should == Kernel
   end
 
-  # On 2.4 with require 'mathn', Math is redefined as CMath
-  ruby_version_is "2.5" do
-    specify "rb_mMath references the Math module" do
-      @s.rb_mMath.should == Math
-    end
+  specify "rb_mMath references the Math module" do
+    @s.rb_mMath.should == Math
   end
 
   specify "rb_cMatch references the MatchData class" do
@@ -216,10 +207,8 @@ describe "C-API exception constant" do
     @s.rb_eFloatDomainError.should == FloatDomainError
   end
 
-  ruby_version_is "2.5" do
-    specify "rb_eFrozenError references the FrozenError class" do
-      @s.rb_eFrozenError.should == FrozenError
-    end
+  specify "rb_eFrozenError references the FrozenError class" do
+    @s.rb_eFrozenError.should == FrozenError
   end
 
   specify "rb_eIndexError references the IndexError class" do
diff --git a/spec/ruby/optional/capi/numeric_spec.rb b/spec/ruby/optional/capi/numeric_spec.rb
index de7e180414..d433d19274 100644
--- a/spec/ruby/optional/capi/numeric_spec.rb
+++ b/spec/ruby/optional/capi/numeric_spec.rb
@@ -437,23 +437,12 @@ describe "CApiNumericSpecs" do
       @s.rb_num_coerce_cmp(2, obj, :<=>).should == -1
     end
 
-    ruby_version_is ""..."2.5" do
-      it "returns nil if passed nil" do
-        -> {
-          @result = @s.rb_num_coerce_cmp(nil, 2, :<=>)
-        }.should complain(/comparison operators will no more rescue exceptions/)
-        @result.should be_nil
-      end
-    end
-
-    ruby_version_is "2.5" do
-      it "lets the exception go through if #coerce raises an exception" do
-        obj = mock("rb_num_coerce_cmp")
-        obj.should_receive(:coerce).with(2).and_raise(RuntimeError.new("my error"))
-        -> {
-          @s.rb_num_coerce_cmp(2, obj, :<=>)
-        }.should raise_error(RuntimeError, "my error")
-      end
+    it "lets the exception go through if #coerce raises an exception" do
+      obj = mock("rb_num_coerce_cmp")
+      obj.should_receive(:coerce).with(2).and_raise(RuntimeError.new("my error"))
+      -> {
+        @s.rb_num_coerce_cmp(2, obj, :<=>)
+      }.should raise_error(RuntimeError, "my error")
     end
 
     it "returns nil if #coerce does not return an Array" do
diff --git a/spec/ruby/optional/capi/time_spec.rb b/spec/ruby/optional/capi/time_spec.rb
index 2c824bb566..579e81fc19 100644
--- a/spec/ruby/optional/capi/time_spec.rb
+++ b/spec/ruby/optional/capi/time_spec.rb
@@ -165,30 +165,28 @@ describe "CApiTimeSpecs" do
       usec.should == 500000
     end
 
-    guard -> { platform_is_not :mingw or ruby_version_is '2.5' } do
-      it "creates a timeval for a negative Fixnum" do
-        sec, usec = @s.rb_time_timeval(-1232141421)
-        sec.should be_kind_of(Integer)
-        sec.should == -1232141421
-        usec.should be_kind_of(Integer)
-        usec.should == 0
-      end
+    it "creates a timeval for a negative Fixnum" do
+      sec, usec = @s.rb_time_timeval(-1232141421)
+      sec.should be_kind_of(Integer)
+      sec.should == -1232141421
+      usec.should be_kind_of(Integer)
+      usec.should == 0
+    end
 
-      it "creates a timeval for a negative Float" do
-        sec, usec = @s.rb_time_timeval(-1.5)
-        sec.should be_kind_of(Integer)
-        sec.should == -2
-        usec.should be_kind_of(Integer)
-        usec.should == 500000
-      end
+    it "creates a timeval for a negative Float" do
+      sec, usec = @s.rb_time_timeval(-1.5)
+      sec.should be_kind_of(Integer)
+      sec.should == -2
+      usec.should be_kind_of(Integer)
+      usec.should == 500000
+    end
 
-      it "creates a timeval for a negative Rational" do
-        sec, usec = @s.rb_time_timeval(Rational(-3, 2))
-        sec.should be_kind_of(Integer)
-        sec.should == -2
-        usec.should be_kind_of(Integer)
-        usec.should == 500000
-      end
+    it "creates a timeval for a negative Rational" do
+      sec, usec = @s.rb_time_timeval(Rational(-3, 2))
+      sec.should be_kind_of(Integer)
+      sec.should == -2
+      usec.should be_kind_of(Integer)
+      usec.should == 500000
     end
 
     it "creates a timeval from a Time object" do
@@ -224,30 +222,28 @@ describe "CApiTimeSpecs" do
       nsec.should == 500000000
     end
 
-    guard -> { platform_is_not :mingw or ruby_version_is '2.5' } do
-      it "creates a timespec for a negative Fixnum" do
-        sec, nsec = @s.rb_time_timespec(-1232141421)
-        sec.should be_kind_of(Integer)
-        sec.should == -1232141421
-        nsec.should be_kind_of(Integer)
-        nsec.should == 0
-      end
+    it "creates a timespec for a negative Fixnum" do
+      sec, nsec = @s.rb_time_timespec(-1232141421)
+      sec.should be_kind_of(Integer)
+      sec.should == -1232141421
+      nsec.should be_kind_of(Integer)
+      nsec.should == 0
+    end
 
-      it "creates a timespec for a negative Float" do
-        sec, nsec = @s.rb_time_timespec(-1.5)
-        sec.should be_kind_of(Integer)
-        sec.should == -2
-        nsec.should be_kind_of(Integer)
-        nsec.should == 500000000
-      end
+    it "creates a timespec for a negative Float" do
+      sec, nsec = @s.rb_time_timespec(-1.5)
+      sec.should be_kind_of(Integer)
+      sec.should == -2
+      nsec.should be_kind_of(Integer)
+      nsec.should == 500000000
+    end
 
-      it "creates a timespec for a negative Rational" do
-        sec, nsec = @s.rb_time_timespec(Rational(-3, 2))
-        sec.should be_kind_of(Integer)
-        sec.should == -2
-        nsec.should be_kind_of(Integer)
-        nsec.should == 500000000
-      end
+    it "creates a timespec for a negative Rational" do
+      sec, nsec = @s.rb_time_timespec(Rational(-3, 2))
+      sec.should be_kind_of(Integer)
+      sec.should == -2
+      nsec.should be_kind_of(Integer)
+      nsec.should == 500000000
     end
 
     it "creates a timespec from a Time object" do
diff --git a/spec/ruby/security/cve_2018_8780_spec.rb b/spec/ruby/security/cve_2018_8780_spec.rb
index 555ce9365c..9942e07ee2 100644
--- a/spec/ruby/security/cve_2018_8780_spec.rb
+++ b/spec/ruby/security/cve_2018_8780_spec.rb
@@ -29,17 +29,15 @@ describe "CVE-2018-8780 is resisted by" do
     }.should raise_error(ArgumentError, /(path name|string) contains null byte/)
   end
 
-  ruby_version_is "2.5" do
-    it "Dir.children by raising an exception when there is a NUL byte" do
-      -> {
-        Dir.children(@root+"\0")
-      }.should raise_error(ArgumentError, /(path name|string) contains null byte/)
-    end
+  it "Dir.children by raising an exception when there is a NUL byte" do
+    -> {
+      Dir.children(@root+"\0")
+    }.should raise_error(ArgumentError, /(path name|string) contains null byte/)
+  end
 
-    it "Dir.each_child by raising an exception when there is a NUL byte" do
-      -> {
-        Dir.each_child(@root+"\0").to_a
-      }.should raise_error(ArgumentError, /(path name|string) contains null byte/)
-    end
+  it "Dir.each_child by raising an exception when there is a NUL byte" do
+    -> {
+      Dir.each_child(@root+"\0").to_a
+    }.should raise_error(ArgumentError, /(path name|string) contains null byte/)
   end
 end
diff --git a/spec/ruby/security/cve_2020_10663_spec.rb b/spec/ruby/security/cve_2020_10663_spec.rb
index 4738ce175e..e305c0b593 100644
--- a/spec/ruby/security/cve_2020_10663_spec.rb
+++ b/spec/ruby/security/cve_2020_10663_spec.rb
@@ -18,7 +18,6 @@ module JSONSpecs
 end
 
 guard -> {
-  ruby_version_is "2.4.10"..."2.5.0" or
   ruby_version_is "2.5.8"..."2.6.0" or
   ruby_version_is "2.6.6" or
   JSON.const_defined?(:Pure) or
diff --git a/spec/ruby/shared/hash/key_error.rb b/spec/ruby/shared/hash/key_error.rb
index 061c88c483..54dcb89e91 100644
--- a/spec/ruby/shared/hash/key_error.rb
+++ b/spec/ruby/shared/hash/key_error.rb
@@ -5,21 +5,19 @@ describe :key_error, shared: true do
     }.should raise_error(KeyError)
   end
 
-  ruby_version_is "2.5" do
-    it "sets the Hash as the receiver of KeyError" do
-      -> {
-        @method.call(@object, 'foo')
-      }.should raise_error(KeyError) { |err|
-        err.receiver.should equal(@object)
-      }
-    end
+  it "sets the Hash as the receiver of KeyError" do
+    -> {
+      @method.call(@object, 'foo')
+    }.should raise_error(KeyError) { |err|
+      err.receiver.should equal(@object)
+    }
+  end
 
-    it "sets the unmatched key as the key of KeyError" do
-      -> {
-        @method.call(@object, 'foo')
-      }.should raise_error(KeyError) { |err|
-        err.key.to_s.should == 'foo'
-      }
-    end
+  it "sets the unmatched key as the key of KeyError" do
+    -> {
+      @method.call(@object, 'foo')
+    }.should raise_error(KeyError) { |err|
+      err.key.to_s.should == 'foo'
+    }
   end
 end
diff --git a/spec/ruby/shared/rational/arithmetic_exception_in_coerce.rb b/spec/ruby/shared/rational/arithmetic_exception_in_coerce.rb
index 9377814732..0dff91d522 100644
--- a/spec/ruby/shared/rational/arithmetic_exception_in_coerce.rb
+++ b/spec/ruby/shared/rational/arithmetic_exception_in_coerce.rb
@@ -1,33 +1,11 @@
 require_relative '../../fixtures/rational'
 
 describe :rational_arithmetic_exception_in_coerce, shared: true do
-  ruby_version_is ""..."2.5" do
-    it "rescues exception (StandardError and subclasses) raised in other#coerce and raises TypeError" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
+  it "does not rescue exception raised in other#coerce" do
+    b = mock("numeric with failed #coerce")
+    b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
 
-      # e.g. Rational(3, 4) + b
-      -> { Rational(3, 4).send(@method, b) }.should raise_error(TypeError, /MockObject can't be coerced into Rational/)
-    end
-
-    it "does not rescue Exception and StandardError siblings raised in other#coerce" do
-      [Exception, NoMemoryError].each do |exception|
-        b = mock("numeric with failed #coerce")
-        b.should_receive(:coerce).and_raise(exception)
-
-        # e.g. Rational(3, 4) + b
-        -> { Rational(3, 4).send(@method, b) }.should raise_error(exception)
-      end
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not rescue exception raised in other#coerce" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
-
-      # e.g. Rational(3, 4) + b
-      -> { Rational(3, 4).send(@method, b) }.should raise_error(RationalSpecs::CoerceError)
-    end
+    # e.g. Rational(3, 4) + b
+    -> { Rational(3, 4).send(@method, b) }.should raise_error(RationalSpecs::CoerceError)
   end
 end
diff --git a/spec/ruby/shared/rational/comparison.rb b/spec/ruby/shared/rational/comparison.rb
index 0c8b3d0ac1..860462f579 100644
--- a/spec/ruby/shared/rational/comparison.rb
+++ b/spec/ruby/shared/rational/comparison.rb
@@ -80,33 +80,11 @@ describe :rational_cmp_coerce, shared: true do
 end
 
 describe :rational_cmp_coerce_exception, shared: true do
-  ruby_version_is ""..."2.5" do
-    it "rescues exception (StandardError and subclasses) raised in other#coerce and returns nil" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
-
-      -> {
-        (Rational(3, 4) <=> b).should == nil
-      }.should complain(/Numerical comparison operators will no more rescue exceptions of #coerce/)
-    end
-
-    it "does not rescue Exception and StandardError siblings raised in other#coerce" do
-      [Exception, NoMemoryError].each do |exception|
-        b = mock("numeric with failed #coerce")
-        b.should_receive(:coerce).and_raise(exception)
-
-        -> { Rational(3, 4) <=> b }.should raise_error(exception)
-      end
-    end
-  end
-
-  ruby_version_is "2.5" do
-    it "does not rescue exception raised in other#coerce" do
-      b = mock("numeric with failed #coerce")
-      b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
+  it "does not rescue exception raised in other#coerce" do
+    b = mock("numeric with failed #coerce")
+    b.should_receive(:coerce).and_raise(RationalSpecs::CoerceError)
 
-      -> { Rational(3, 4) <=> b }.should raise_error(RationalSpecs::CoerceError)
-    end
+    -> { Rational(3, 4) <=> b }.should raise_error(RationalSpecs::CoerceError)
   end
 end