1 files changed, 15 insertions, 28 deletions

diff --git a/spec/ruby/core/string/tr_spec.rb b/spec/ruby/core/string/tr_spec.rb
index 06be1e6641..cb57c3851e 100644
--- a/spec/ruby/core/string/tr_spec.rb
+++ b/spec/ruby/core/string/tr_spec.rb
@@ -1,4 +1,5 @@
 # -*- encoding: utf-8 -*-
+# frozen_string_literal: false
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 
@@ -16,17 +17,24 @@ describe "String#tr" do
     "hello ^-^".tr("---", "_").should == "hello ^_^"
   end
 
+  it "accepts c1-c1 notation to denote range of one character" do
+    "hello".tr('e-e', 'x').should == "hxllo"
+    "123456789".tr("2-23","xy").should == "1xy456789"
+    "hello ^-^".tr("e-", "a-a_").should == "hallo ^_^"
+    "hello ^-^".tr("---o", "_a").should == "hella ^_^"
+  end
+
   it "pads to_str with its last char if it is shorter than from_string" do
     "this".tr("this", "x").should == "xxxx"
     "hello".tr("a-z", "A-H.").should == "HE..."
   end
 
   it "raises an ArgumentError a descending range in the replacement as containing just the start character" do
-    -> { "hello".tr("a-y", "z-b") }.should raise_error(ArgumentError)
+    -> { "hello".tr("a-y", "z-b") }.should.raise(ArgumentError)
   end
 
   it "raises an ArgumentError a descending range in the source as empty" do
-    -> { "hello".tr("l-a", "z") }.should raise_error(ArgumentError)
+    -> { "hello".tr("l-a", "z") }.should.raise(ArgumentError)
   end
 
   it "translates chars not in from_string when it starts with a ^" do
@@ -57,29 +65,8 @@ describe "String#tr" do
     "bla".tr(from_str, to_str).should == "BlA"
   end
 
-  ruby_version_is ''...'3.0' do
-    it "returns subclass instances when called on a subclass" do
-      StringSpecs::MyString.new("hello").tr("e", "a").should be_an_instance_of(StringSpecs::MyString)
-    end
-  end
-
-  ruby_version_is '3.0' do
-    it "returns Stringinstances when called on a subclass" do
-      StringSpecs::MyString.new("hello").tr("e", "a").should be_an_instance_of(String)
-    end
-  end
-
-  ruby_version_is ''...'2.7' do
-    it "taints the result when self is tainted" do
-      ["h", "hello"].each do |str|
-        tainted_str = str.dup.taint
-
-        tainted_str.tr("e", "a").should.tainted?
-
-        str.tr("e".taint, "a").should_not.tainted?
-        str.tr("e", "a".taint).should_not.tainted?
-      end
-    end
+  it "returns Stringinstances when called on a subclass" do
+    StringSpecs::MyString.new("hello").tr("e", "a").should.instance_of?(String)
   end
 
   # http://redmine.ruby-lang.org/issues/show/1839
@@ -132,8 +119,8 @@ describe "String#tr!" do
 
   it "raises a FrozenError if self is frozen" do
     s = "abcdefghijklmnopqR".freeze
-    -> { s.tr!("cdefg", "12") }.should raise_error(FrozenError)
-    -> { s.tr!("R", "S")      }.should raise_error(FrozenError)
-    -> { s.tr!("", "")        }.should raise_error(FrozenError)
+    -> { s.tr!("cdefg", "12") }.should.raise(FrozenError)
+    -> { s.tr!("R", "S")      }.should.raise(FrozenError)
+    -> { s.tr!("", "")        }.should.raise(FrozenError)
   end
 end