Update to ruby/spec@abf1700

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59205 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

50 files changed, 695 insertions, 258 deletions

diff --git a/spec/rubyspec/core/argf/binmode_spec.rb b/spec/rubyspec/core/argf/binmode_spec.rb
index 3daf4f4345..62202360e3 100644
--- a/spec/rubyspec/core/argf/binmode_spec.rb
+++ b/spec/rubyspec/core/argf/binmode_spec.rb
@@ -8,7 +8,9 @@ describe "ARGF.binmode" do
   end
 
   it "returns self" do
-    ruby_exe("puts(ARGF.binmode == ARGF)", args: @bin_file).chomp.should == 'true'
+    argf [@bin_file] do
+      @argf.binmode.should equal @argf
+    end
   end
 
   platform_is :windows do
@@ -29,18 +31,13 @@ describe "ARGF.binmode" do
     end
   end
 
-  platform_is_not :windows do
-    # This does nothing on Unix but it should not raise any errors.
-    it "does not raise an error" do
-      ruby_exe("ARGF.binmode", args: @bin_file)
-      $?.should  be_kind_of(Process::Status)
-      $?.to_i.should == 0
-    end
-  end
-
   it "sets the file's encoding to ASCII-8BIT" do
-    script = fixture __FILE__, "encoding.rb"
-    output = "true\n#{Encoding::ASCII_8BIT}\n#{Encoding::ASCII_8BIT}\n"
-    ruby_exe(script, args: [@bin_file, @file1]).should == output
+    argf [@bin_file, @file1] do
+      @argf.binmode
+      @argf.binmode?.should == true
+      @argf.gets.encoding.should == Encoding::ASCII_8BIT
+      @argf.skip
+      @argf.read.encoding.should == Encoding::ASCII_8BIT
+    end
   end
 end
diff --git a/spec/rubyspec/core/argf/fixtures/encoding.rb b/spec/rubyspec/core/argf/fixtures/encoding.rb
deleted file mode 100644
index 6e87e64346..0000000000
--- a/spec/rubyspec/core/argf/fixtures/encoding.rb
+++ /dev/null
@@ -1,5 +0,0 @@
-ARGF.binmode
-puts ARGF.binmode?
-puts ARGF.gets.encoding
-ARGF.skip
-puts ARGF.read.encoding
diff --git a/spec/rubyspec/core/argf/set_encoding_spec.rb b/spec/rubyspec/core/argf/set_encoding_spec.rb
index 16d49a8c44..f6ec74ded1 100644
--- a/spec/rubyspec/core/argf/set_encoding_spec.rb
+++ b/spec/rubyspec/core/argf/set_encoding_spec.rb
@@ -1,28 +1,41 @@
 require File.expand_path('../../../spec_helper', __FILE__)
 
-# These specs need to be run to a separate process as there is no way to reset ARGF encoding
 describe "ARGF.set_encoding" do
   before :each do
     @file = fixture __FILE__, "file1.txt"
   end
 
   it "sets the external encoding when passed an encoding instance" do
-    enc = ruby_exe('ARGF.set_encoding(Encoding::UTF_8); print ARGF.gets.encoding', args: [@file])
-    enc.should == "UTF-8"
+    argf [@file] do
+      @argf.set_encoding(Encoding::US_ASCII)
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.gets.encoding.should == Encoding::US_ASCII
+    end
   end
 
   it "sets the external encoding when passed an encoding name" do
-    enc = ruby_exe('ARGF.set_encoding("utf-8"); print ARGF.gets.encoding', args: [@file])
-    enc.should == "UTF-8"
+    argf [@file] do
+      @argf.set_encoding("us-ascii")
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.gets.encoding.should == Encoding::US_ASCII
+    end
   end
 
   it "sets the external, internal encoding when passed two encoding instances" do
-    enc = ruby_exe('ARGF.set_encoding(Encoding::UTF_8, Encoding::EUC_JP); print ARGF.gets.encoding', args: [@file])
-    enc.should == "EUC-JP"
+    argf [@file] do
+      @argf.set_encoding(Encoding::US_ASCII, Encoding::EUC_JP)
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.internal_encoding.should == Encoding::EUC_JP
+      @argf.gets.encoding.should == Encoding::EUC_JP
+    end
   end
 
   it "sets the external, internal encoding when passed 'ext:int' String" do
-    enc = ruby_exe('ARGF.set_encoding("utf-8:euc-jp"); print ARGF.gets.encoding', args: [@file])
-    enc.should == "EUC-JP"
+    argf [@file] do
+      @argf.set_encoding("us-ascii:euc-jp")
+      @argf.external_encoding.should == Encoding::US_ASCII
+      @argf.internal_encoding.should == Encoding::EUC_JP
+      @argf.gets.encoding.should == Encoding::EUC_JP
+    end
   end
 end
diff --git a/spec/rubyspec/core/array/element_set_spec.rb b/spec/rubyspec/core/array/element_set_spec.rb
index 280b507fc4..6544ad9b6f 100644
--- a/spec/rubyspec/core/array/element_set_spec.rb
+++ b/spec/rubyspec/core/array/element_set_spec.rb
@@ -258,12 +258,12 @@ describe "Array#[]= with [index]" do
   end
 
   it "sets the value of the element at index" do
-      a = [1, 2, 3, 4]
-      a[2] = 5
-      a[-1] = 6
-      a[5] = 3
-      a.should == [1, 2, 5, 6, nil, 3]
-    end
+    a = [1, 2, 3, 4]
+    a[2] = 5
+    a[-1] = 6
+    a[5] = 3
+    a.should == [1, 2, 5, 6, nil, 3]
+  end
 
   it "sets the value of the element if it is right beyond the array boundary" do
     a = [1, 2, 3, 4]
@@ -370,11 +370,11 @@ describe "Array#[]= with [m..n]" do
   end
 
   it "replaces the section defined by range" do
-      a = [6, 5, 4, 3, 2, 1]
-      a[1...2] = 9
-      a[3..6] = [6, 6, 6]
-      a.should == [6, 9, 4, 6, 6, 6]
-    end
+    a = [6, 5, 4, 3, 2, 1]
+    a[1...2] = 9
+    a[3..6] = [6, 6, 6]
+    a.should == [6, 9, 4, 6, 6, 6]
+  end
 
   it "replaces the section if m and n < 0" do
     a = [1, 2, 3, 4, 5]
@@ -415,4 +415,3 @@ describe "Array#[] after a shift" do
     a.should == [3,4]
   end
 end
-
diff --git a/spec/rubyspec/core/array/shared/inspect.rb b/spec/rubyspec/core/array/shared/inspect.rb
index 823dd40e7e..6a60781b45 100644
--- a/spec/rubyspec/core/array/shared/inspect.rb
+++ b/spec/rubyspec/core/array/shared/inspect.rb
@@ -18,6 +18,46 @@ describe :array_inspect, shared: true do
     items.send(@method).should == "[0, 1, 2]"
   end
 
+  it "does not call #to_s on a String returned from #inspect" do
+    str = "abc"
+    str.should_not_receive(:to_s)
+
+    [str].send(@method).should == '["abc"]'
+  end
+
+  it "calls #to_s on the object returned from #inspect if the Object isn't a String" do
+    obj = mock("Array#inspect/to_s calls #to_s")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_return("abc")
+
+    [obj].send(@method).should == "[abc]"
+  end
+
+  it "does not call #to_str on the object returned from #inspect when it is not a String" do
+    obj = mock("Array#inspect/to_s does not call #to_str")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_not_receive(:to_str)
+
+    [obj].send(@method).should =~ /^\[#<MockObject:0x[0-9a-f]+>\]$/
+  end
+
+  it "does not call #to_str on the object returned from #to_s when it is not a String" do
+    obj = mock("Array#inspect/to_s does not call #to_str on #to_s result")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_return(obj)
+    obj.should_not_receive(:to_str)
+
+    [obj].send(@method).should =~ /^\[#<MockObject:0x[0-9a-f]+>\]$/
+  end
+
+  it "does not swallow exceptions raised by #to_s" do
+    obj = mock("Array#inspect/to_s does not swallow #to_s exceptions")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_raise(Exception)
+
+    lambda { [obj].send(@method) }.should raise_error(Exception)
+  end
+
   it "represents a recursive element with '[...]'" do
     ArraySpecs.recursive_array.send(@method).should == "[1, \"two\", 3.0, [...], [...], [...], [...], [...]]"
     ArraySpecs.head_recursive_array.send(@method).should == "[[...], [...], [...], [...], [...], 1, \"two\", 3.0]"
diff --git a/spec/rubyspec/core/basicobject/equal_spec.rb b/spec/rubyspec/core/basicobject/equal_spec.rb
index 8142efa6bd..8120df836f 100644
--- a/spec/rubyspec/core/basicobject/equal_spec.rb
+++ b/spec/rubyspec/core/basicobject/equal_spec.rb
@@ -10,9 +10,9 @@ describe "BasicObject#equal?" do
 
   it "is unaffected by overriding __id__" do
     o1 = mock("object")
-    o1.stub!(:__id__).and_return(10)
     o2 = mock("object")
-    o2.stub!(:__id__).and_return(10)
+    def o1.__id__; 10; end
+    def o2.__id__; 10; end
     o1.equal?(o2).should be_false
   end
 
diff --git a/spec/rubyspec/core/bignum/bignum_spec.rb b/spec/rubyspec/core/bignum/bignum_spec.rb
index b723718f69..cf99bb4937 100644
--- a/spec/rubyspec/core/bignum/bignum_spec.rb
+++ b/spec/rubyspec/core/bignum/bignum_spec.rb
@@ -4,4 +4,16 @@ describe "Bignum" do
   it "includes Comparable" do
     Bignum.include?(Comparable).should == true
   end
+
+  it ".allocate raises a TypeError" do
+    lambda do
+      Bignum.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      Bignum.new
+    end.should raise_error(NoMethodError)
+  end
 end
diff --git a/spec/rubyspec/core/enumerable/sum_spec.rb b/spec/rubyspec/core/enumerable/sum_spec.rb
new file mode 100644
index 0000000000..4881039a8d
--- /dev/null
+++ b/spec/rubyspec/core/enumerable/sum_spec.rb
@@ -0,0 +1,30 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+ruby_version_is '2.4' do
+  describe 'Enumerable#sum' do
+    before :each do
+      @enum = Object.new.to_enum
+      class << @enum
+        def each
+          yield 0
+          yield(-1)
+          yield 2
+          yield 2/3r
+        end
+      end
+    end
+
+    it 'returns amount of the elements with taking an argument as the initial value' do
+      @enum.sum(10).should == 35/3r
+    end
+
+    it 'gives 0 as a default argument' do
+      @enum.sum.should == 5/3r
+    end
+
+    it 'takes a block to transform the elements' do
+      @enum.sum { |element| element * 2 }.should == 10/3r
+    end
+  end
+end
diff --git a/spec/rubyspec/core/enumerable/uniq_spec.rb b/spec/rubyspec/core/enumerable/uniq_spec.rb
new file mode 100644
index 0000000000..0ede0170ce
--- /dev/null
+++ b/spec/rubyspec/core/enumerable/uniq_spec.rb
@@ -0,0 +1,29 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+ruby_version_is '2.4' do
+  describe 'Enumerable#uniq' do
+    it 'returns an array that contains only unique elements' do
+      [0, 1, 2, 3].to_enum.uniq { |n| n.even? }.should == [0, 1]
+    end
+
+    context 'when yielded with multiple arguments' do
+      before :each do
+        @enum = Object.new.to_enum
+        class << @enum
+          def each
+            yield 0, 'foo'
+            yield 1, 'FOO'
+            yield 2, 'bar'
+          end
+        end
+      end
+
+      ruby_bug '#13669', ''...'2.5' do
+        it 'returns all yield arguments as an array' do
+          @enum.uniq { |_, label| label.downcase }.should == [[0, 'foo'], [2, 'bar']]
+        end
+      end
+    end
+  end
+end
diff --git a/spec/rubyspec/core/enumerator/inspect_spec.rb b/spec/rubyspec/core/enumerator/inspect_spec.rb
index e89d3b7f3a..b708256247 100644
--- a/spec/rubyspec/core/enumerator/inspect_spec.rb
+++ b/spec/rubyspec/core/enumerator/inspect_spec.rb
@@ -1,5 +1,17 @@
 require File.expand_path('../../../spec_helper', __FILE__)
 
 describe "Enumerator#inspect" do
-  it "needs to be reviewed for spec completeness"
+  describe "shows a representation of the Enumerator" do
+    it "including receiver and method" do
+      (1..3).each.inspect.should == "#<Enumerator: 1..3:each>"
+    end
+
+    it "including receiver and method and arguments" do
+      (1..3).each_slice(2).inspect.should == "#<Enumerator: 1..3:each_slice(2)>"
+    end
+
+    it "including the nested Enumerator" do
+      (1..3).each.each_slice(2).inspect.should == "#<Enumerator: #<Enumerator: 1..3:each>:each_slice(2)>"
+    end
+  end
 end
diff --git a/spec/rubyspec/core/enumerator/lazy/grep_spec.rb b/spec/rubyspec/core/enumerator/lazy/grep_spec.rb
index c5fbfcf1dd..372be80d61 100644
--- a/spec/rubyspec/core/enumerator/lazy/grep_spec.rb
+++ b/spec/rubyspec/core/enumerator/lazy/grep_spec.rb
@@ -64,7 +64,7 @@ describe "Enumerator::Lazy#grep" do
     end
 
     describe "when the returned lazy enumerator is evaluated by Enumerable#first" do
-     it "stops after specified times when not given a block" do
+      it "stops after specified times when not given a block" do
         (0..Float::INFINITY).lazy.grep(Integer).grep(Object).first(3).should == [0, 1, 2]
 
         @eventsmixed.grep(BasicObject).grep(Object).first(1)
diff --git a/spec/rubyspec/core/enumerator/lazy/grep_v_spec.rb b/spec/rubyspec/core/enumerator/lazy/grep_v_spec.rb
index 06dd42213c..123cbae58c 100644
--- a/spec/rubyspec/core/enumerator/lazy/grep_v_spec.rb
+++ b/spec/rubyspec/core/enumerator/lazy/grep_v_spec.rb
@@ -63,7 +63,7 @@ ruby_version_is "2.3" do
       end
 
       describe "when the returned lazy enumerator is evaluated by Enumerable#first" do
-       it "stops after specified times when not given a block" do
+        it "stops after specified times when not given a block" do
           (0..Float::INFINITY).lazy.grep_v(3..5).grep_v(6..10).first(3).should == [0, 1, 2]
 
           @eventsmixed.grep_v(Symbol).grep_v(String).first(1)
diff --git a/spec/rubyspec/core/enumerator/lazy/uniq_spec.rb b/spec/rubyspec/core/enumerator/lazy/uniq_spec.rb
new file mode 100644
index 0000000000..6220c7ba34
--- /dev/null
+++ b/spec/rubyspec/core/enumerator/lazy/uniq_spec.rb
@@ -0,0 +1,39 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+ruby_version_is '2.4' do
+  describe 'Enumerator::Lazy#uniq' do
+    context 'when yielded with an argument' do
+      before :each do
+        @lazy = [0, 1, 2, 3].to_enum.lazy.uniq(&:even?)
+      end
+
+      it 'returns a lazy enumerator' do
+        @lazy.should be_an_instance_of(Enumerator::Lazy)
+        @lazy.force.should == [0, 1]
+      end
+
+      it 'sets the size to nil' do
+        @lazy.size.should == nil
+      end
+    end
+
+    context 'when yielded with multiple arguments' do
+      before :each do
+        enum = Object.new.to_enum
+        class << enum
+          def each
+            yield 0, 'foo'
+            yield 1, 'FOO'
+            yield 2, 'bar'
+          end
+        end
+        @lazy = enum.lazy
+      end
+
+      it 'returns all yield arguments as an array' do
+        @lazy.uniq { |_, label| label.downcase }.force.should == [[0, 'foo'], [2, 'bar']]
+      end
+    end
+  end
+end
diff --git a/spec/rubyspec/core/false/falseclass_spec.rb b/spec/rubyspec/core/false/falseclass_spec.rb
new file mode 100644
index 0000000000..e91682c94c
--- /dev/null
+++ b/spec/rubyspec/core/false/falseclass_spec.rb
@@ -0,0 +1,15 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "FalseClass" do
+  it ".allocate raises a TypeError" do
+    lambda do
+      FalseClass.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      FalseClass.new
+    end.should raise_error(NoMethodError)
+  end
+end
diff --git a/spec/rubyspec/core/fixnum/bit_and_spec.rb b/spec/rubyspec/core/fixnum/bit_and_spec.rb
index ff0e597a52..9586075039 100644
--- a/spec/rubyspec/core/fixnum/bit_and_spec.rb
+++ b/spec/rubyspec/core/fixnum/bit_and_spec.rb
@@ -27,6 +27,12 @@ describe "Fixnum#&" do
     (-1 & 2**64).should == 18446744073709551616
   end
 
+  it "coerces the rhs and calls #coerce" do
+    obj = mock("fixnum bit and")
+    obj.should_receive(:coerce).with(6).and_return([3, 6])
+    (6 & obj).should == 2
+  end
+
   it "raises a TypeError when passed a Float" do
     lambda { (3 & 3.4) }.should raise_error(TypeError)
   end
diff --git a/spec/rubyspec/core/fixnum/fixnum_spec.rb b/spec/rubyspec/core/fixnum/fixnum_spec.rb
index d0af975c59..8a050fd25e 100644
--- a/spec/rubyspec/core/fixnum/fixnum_spec.rb
+++ b/spec/rubyspec/core/fixnum/fixnum_spec.rb
@@ -4,4 +4,16 @@ describe "Fixnum" do
   it "includes Comparable" do
     Fixnum.include?(Comparable).should == true
   end
+
+  it ".allocate raises a TypeError" do
+    lambda do
+      Fixnum.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      Fixnum.new
+    end.should raise_error(NoMethodError)
+  end
 end
diff --git a/spec/rubyspec/core/float/float_spec.rb b/spec/rubyspec/core/float/float_spec.rb
index e26e082a55..f2931d184c 100644
--- a/spec/rubyspec/core/float/float_spec.rb
+++ b/spec/rubyspec/core/float/float_spec.rb
@@ -4,4 +4,16 @@ describe "Float" do
   it "includes Comparable" do
     Float.include?(Comparable).should == true
   end
+
+  it ".allocate raises a TypeError" do
+    lambda do
+      Float.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      Float.new
+    end.should raise_error(NoMethodError)
+  end
 end
diff --git a/spec/rubyspec/core/float/shared/modulo.rb b/spec/rubyspec/core/float/shared/modulo.rb
index 9ac967389c..6c423a3a28 100644
--- a/spec/rubyspec/core/float/shared/modulo.rb
+++ b/spec/rubyspec/core/float/shared/modulo.rb
@@ -35,6 +35,12 @@ describe :float_modulo, shared: true do
     (1/r).should < 0
   end
 
+  it "tries to coerce the modulus" do
+    obj = mock("modulus")
+    obj.should_receive(:coerce).with(1.25).and_return([1.25, 0.5])
+    (1.25 % obj).should == 0.25
+  end
+
   it "raises a ZeroDivisionError if other is zero" do
     lambda { 1.0.send(@method, 0) }.should raise_error(ZeroDivisionError)
     lambda { 1.0.send(@method, 0.0) }.should raise_error(ZeroDivisionError)
diff --git a/spec/rubyspec/core/hash/shared/to_s.rb b/spec/rubyspec/core/hash/shared/to_s.rb
index 7ef2c207d4..0afe605826 100644
--- a/spec/rubyspec/core/hash/shared/to_s.rb
+++ b/spec/rubyspec/core/hash/shared/to_s.rb
@@ -15,7 +15,7 @@ describe :hash_to_s, shared: true do
     h.send(@method).should == str
   end
 
-  it "calls inspect on keys and values" do
+  it "calls #inspect on keys and values" do
     key = mock('key')
     val = mock('val')
     key.should_receive(:inspect).and_return('key')
@@ -24,6 +24,46 @@ describe :hash_to_s, shared: true do
     { key => val }.send(@method).should == '{key=>val}'
   end
 
+  it "does not call #to_s on a String returned from #inspect" do
+    str = "abc"
+    str.should_not_receive(:to_s)
+
+    { a: str }.send(@method).should == '{:a=>"abc"}'
+  end
+
+  it "calls #to_s on the object returned from #inspect if the Object isn't a String" do
+    obj = mock("Hash#inspect/to_s calls #to_s")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_return("abc")
+
+    { a: obj }.send(@method).should == "{:a=>abc}"
+  end
+
+  it "does not call #to_str on the object returned from #inspect when it is not a String" do
+    obj = mock("Hash#inspect/to_s does not call #to_str")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_not_receive(:to_str)
+
+    { a: obj }.send(@method).should =~ /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+  end
+
+  it "does not call #to_str on the object returned from #to_s when it is not a String" do
+    obj = mock("Hash#inspect/to_s does not call #to_str on #to_s result")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_return(obj)
+    obj.should_not_receive(:to_str)
+
+    { a: obj }.send(@method).should =~ /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+  end
+
+  it "does not swallow exceptions raised by #to_s" do
+    obj = mock("Hash#inspect/to_s does not swallow #to_s exceptions")
+    obj.should_receive(:inspect).and_return(obj)
+    obj.should_receive(:to_s).and_raise(Exception)
+
+    lambda { { a: obj }.send(@method) }.should raise_error(Exception)
+  end
+
   it "handles hashes with recursive values" do
     x = {}
     x[0] = x
diff --git a/spec/rubyspec/core/io/output_spec.rb b/spec/rubyspec/core/io/output_spec.rb
index ac3e781cee..2d52315430 100644
--- a/spec/rubyspec/core/io/output_spec.rb
+++ b/spec/rubyspec/core/io/output_spec.rb
@@ -9,10 +9,10 @@ describe "IO#<<" do
   end
 
   it "calls #to_s on the object to print it" do
-     lambda {
-       $stderr << 1337
+    lambda {
+      $stderr << 1337
     }.should output_to_fd("1337", $stderr)
-   end
+  end
 
   it "raises an error if the stream is closed" do
     io = IOSpecs.closed_io
diff --git a/spec/rubyspec/core/io/popen_spec.rb b/spec/rubyspec/core/io/popen_spec.rb
index f24e61032f..45bb0e2cab 100644
--- a/spec/rubyspec/core/io/popen_spec.rb
+++ b/spec/rubyspec/core/io/popen_spec.rb
@@ -74,10 +74,7 @@ describe "IO.popen" do
   end
 
   it "does not throw an exception if child exited and has been waited for" do
-    # Avoid the /bin/sh subshell using :options and :args to sleep.
-    # We don't want to kill only the subshell and leave "ruby -e sleep"
-    # running indefinitely
-    @io = IO.popen(ruby_cmd(nil, :options => '-e', :args => 'sleep'))
+    @io = IO.popen([*ruby_exe, '-e', 'sleep'])
     pid = @io.pid
     Process.kill "KILL", pid
     @io.close
@@ -201,28 +198,28 @@ describe "IO.popen" do
     end
 
     it "accepts an Array of command and arguments" do
-      exe, *args = ruby_cmd(nil).split
+      exe, *args = ruby_exe
       IO.popen({"FOO" => "bar"}, [[exe, "specfu"], *args, "-e", "puts ENV['FOO']"]) do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts an Array of command and arguments, and an IO mode" do
-      exe, *args = ruby_cmd(nil).split
+      exe, *args = ruby_exe
       IO.popen({"FOO" => "bar"}, [[exe, "specfu"], *args, "-e", "puts ENV['FOO']"], "r") do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts an Array command with a separate trailing Hash of Process.exec options" do
-      IO.popen({"FOO" => "bar"}, [*ruby_cmd(nil).split, "-e", "STDERR.puts ENV['FOO']"],
+      IO.popen({"FOO" => "bar"}, [*ruby_exe, "-e", "STDERR.puts ENV['FOO']"],
                err: [:child, :out]) do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts an Array command with a separate trailing Hash of Process.exec options, and an IO mode" do
-      IO.popen({"FOO" => "bar"}, [*ruby_cmd(nil).split, "-e", "STDERR.puts ENV['FOO']"],
+      IO.popen({"FOO" => "bar"}, [*ruby_exe, "-e", "STDERR.puts ENV['FOO']"],
                "r", err: [:child, :out]) do |io|
         io.read.should == "bar\n"
       end
@@ -231,45 +228,45 @@ describe "IO.popen" do
 
   context "with a leading Array argument" do
     it "uses the Array as command plus args for the child process" do
-      IO.popen([*ruby_cmd(nil).split, "-e", "puts 'hello'"]) do |io|
+      IO.popen([*ruby_exe, "-e", "puts 'hello'"]) do |io|
         io.read.should == "hello\n"
       end
     end
 
     it "accepts a leading ENV Hash" do
-      IO.popen([{"FOO" => "bar"}, *ruby_cmd(nil).split, "-e", "puts ENV['FOO']"]) do |io|
+      IO.popen([{"FOO" => "bar"}, *ruby_exe, "-e", "puts ENV['FOO']"]) do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts a trailing Hash of Process.exec options" do
-      IO.popen([*ruby_cmd(nil).split, "does_not_exist", {err: [:child, :out]}]) do |io|
+      IO.popen([*ruby_exe, "does_not_exist", {err: [:child, :out]}]) do |io|
         io.read.should =~ /LoadError/
       end
     end
 
     it "accepts an IO mode argument following the Array" do
-      IO.popen([*ruby_cmd(nil).split, "does_not_exist", {err: [:child, :out]}], "r") do |io|
+      IO.popen([*ruby_exe, "does_not_exist", {err: [:child, :out]}], "r") do |io|
         io.read.should =~ /LoadError/
       end
     end
 
     it "accepts [env, command, arg1, arg2, ..., exec options]" do
-      IO.popen([{"FOO" => "bar"}, *ruby_cmd(nil).split, "-e", "STDERR.puts ENV[:FOO.to_s]",
+      IO.popen([{"FOO" => "bar"}, *ruby_exe, "-e", "STDERR.puts ENV[:FOO.to_s]",
                 err: [:child, :out]]) do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts '[env, command, arg1, arg2, ..., exec options], mode'" do
-      IO.popen([{"FOO" => "bar"}, *ruby_cmd(nil).split, "-e", "STDERR.puts ENV[:FOO.to_s]",
+      IO.popen([{"FOO" => "bar"}, *ruby_exe, "-e", "STDERR.puts ENV[:FOO.to_s]",
                 err: [:child, :out]], "r") do |io|
         io.read.should == "bar\n"
       end
     end
 
     it "accepts '[env, command, arg1, arg2, ..., exec options], mode, IO options'" do
-      IO.popen([{"FOO" => "bar"}, *ruby_cmd(nil).split, "-e", "STDERR.puts ENV[:FOO.to_s]",
+      IO.popen([{"FOO" => "bar"}, *ruby_exe, "-e", "STDERR.puts ENV[:FOO.to_s]",
                 err: [:child, :out]], "r",
                internal_encoding: Encoding::EUC_JP) do |io|
         io.read.should == "bar\n"
@@ -278,7 +275,7 @@ describe "IO.popen" do
     end
 
     it "accepts '[env, command, arg1, arg2, ...], mode, IO + exec options'" do
-      IO.popen([{"FOO" => "bar"}, *ruby_cmd(nil).split, "-e", "STDERR.puts ENV[:FOO.to_s]"], "r",
+      IO.popen([{"FOO" => "bar"}, *ruby_exe, "-e", "STDERR.puts ENV[:FOO.to_s]"], "r",
                err: [:child, :out], internal_encoding: Encoding::EUC_JP) do |io|
         io.read.should == "bar\n"
         io.internal_encoding.should == Encoding::EUC_JP
diff --git a/spec/rubyspec/core/kernel/autoload_spec.rb b/spec/rubyspec/core/kernel/autoload_spec.rb
index 082903e92d..e2741de74c 100644
--- a/spec/rubyspec/core/kernel/autoload_spec.rb
+++ b/spec/rubyspec/core/kernel/autoload_spec.rb
@@ -49,8 +49,7 @@ describe "Kernel#autoload" do
   end
 
   it "can autoload in instance_eval" do
-    instance_eval do
-      # this instance_eval is not needed because specs are run in instance_eval
+    Object.new.instance_eval do
       autoload :KSAutoloadD, fixture(__FILE__, "autoload_d.rb")
       KSAutoloadD.loaded.should == :ksautoload_d
     end
diff --git a/spec/rubyspec/core/kernel/caller_spec.rb b/spec/rubyspec/core/kernel/caller_spec.rb
index 94fbe3ab7e..d9be29a8db 100644
--- a/spec/rubyspec/core/kernel/caller_spec.rb
+++ b/spec/rubyspec/core/kernel/caller_spec.rb
@@ -22,6 +22,12 @@ describe 'Kernel#caller' do
     locations.length.should == 1
   end
 
+  it 'returns an Array of caller locations using a range' do
+    locations = KernelSpecs::CallerTest.locations(1..1)
+
+    locations.length.should == 1
+  end
+
   it 'returns the locations as String instances' do
     locations = KernelSpecs::CallerTest.locations
     line      = __LINE__ - 1
diff --git a/spec/rubyspec/core/kernel/chomp_spec.rb b/spec/rubyspec/core/kernel/chomp_spec.rb
index 4b34784169..524a4c8b1d 100644
--- a/spec/rubyspec/core/kernel/chomp_spec.rb
+++ b/spec/rubyspec/core/kernel/chomp_spec.rb
@@ -53,7 +53,7 @@ with_feature :encoding do
 
     it "removes the final carriage return, newline from a multi-byte $_" do
       script = fixture __FILE__, "#{@method}.rb"
-      KernelSpecs.encoded_chomp(script).should == "あれ"
+      KernelSpecs.run_with_dash_n(script).should == "あれ"
     end
   end
 
diff --git a/spec/rubyspec/core/kernel/chop_spec.rb b/spec/rubyspec/core/kernel/chop_spec.rb
index 53b6e47cd1..5106fefee8 100644
--- a/spec/rubyspec/core/kernel/chop_spec.rb
+++ b/spec/rubyspec/core/kernel/chop_spec.rb
@@ -41,7 +41,7 @@ with_feature :encoding do
 
     it "removes the final multi-byte character from $_" do
       script = fixture __FILE__, "#{@method}.rb"
-      KernelSpecs.encoded_chop(script).should == "あ"
+      KernelSpecs.run_with_dash_n(script).should == "あ"
     end
   end
 
diff --git a/spec/rubyspec/core/kernel/clone_spec.rb b/spec/rubyspec/core/kernel/clone_spec.rb
index 0e8216d434..48b3c24c7f 100644
--- a/spec/rubyspec/core/kernel/clone_spec.rb
+++ b/spec/rubyspec/core/kernel/clone_spec.rb
@@ -37,6 +37,16 @@ describe "Kernel#clone" do
     o3.frozen?.should == true
   end
 
+  ruby_version_is '2.4' do
+    it 'takes an option to copy freeze state or not' do
+      @obj.clone(freeze: true).frozen?.should == false
+      @obj.clone(freeze: false).frozen?.should == false
+      @obj.freeze
+      @obj.clone(freeze: true).frozen?.should == true
+      @obj.clone(freeze: false).frozen?.should == false
+    end
+  end
+
   it "copies instance variables" do
     clone = @obj.clone
     clone.one.should == 1
diff --git a/spec/rubyspec/core/kernel/fixtures/classes.rb b/spec/rubyspec/core/kernel/fixtures/classes.rb
index c4a4d00485..afa2bec12f 100644
--- a/spec/rubyspec/core/kernel/fixtures/classes.rb
+++ b/spec/rubyspec/core/kernel/fixtures/classes.rb
@@ -32,26 +32,36 @@ module KernelSpecs
   end
 
   def self.has_private_method(name)
-    cmd = %[| #{ruby_cmd(nil)} -n -e "print Kernel.private_method_defined?('#{name}')"]
-    ruby_exe("puts", args: cmd) == "true"
+    IO.popen([*ruby_exe, "-n", "-e", "print Kernel.private_method_defined?(#{name.inspect})"], "r+") do |io|
+      io.puts
+      io.close_write
+      io.read
+    end == "true"
   end
 
   def self.chop(str, method)
-    cmd = "| #{ruby_cmd(nil)} -n -e '$_ = #{str.inspect}; #{method}; print $_'"
-    ruby_exe "puts", args: cmd
-  end
-
-  def self.encoded_chop(file)
-    ruby_exe "puts", args: "| #{ruby_cmd(nil)} -n #{file}"
+    IO.popen([*ruby_exe, "-n", "-e", "$_ = #{str.inspect}; #{method}; print $_"], "r+") do |io|
+      io.puts
+      io.close_write
+      io.read
+    end
   end
 
   def self.chomp(str, method, sep="\n")
-    cmd = "| #{ruby_cmd(nil)} -n -e '$_ = #{str.inspect}; $/ = #{sep.inspect}; #{method}; print $_'"
-    ruby_exe "puts", args: cmd
+    code = "$_ = #{str.inspect}; $/ = #{sep.inspect}; #{method}; print $_"
+    IO.popen([*ruby_exe, "-n", "-e", code], "r+") do |io|
+      io.puts
+      io.close_write
+      io.read
+    end
   end
 
-  def self.encoded_chomp(file)
-    ruby_exe "puts", args: "| #{ruby_cmd(nil)} -n #{file}"
+  def self.run_with_dash_n(file)
+    IO.popen([*ruby_exe, "-n", file], "r+") do |io|
+      io.puts
+      io.close_write
+      io.read
+    end
   end
 
   # kind_of?, is_a?, instance_of?
diff --git a/spec/rubyspec/core/kernel/public_method_spec.rb b/spec/rubyspec/core/kernel/public_method_spec.rb
index c4a29d9192..f1cc168420 100644
--- a/spec/rubyspec/core/kernel/public_method_spec.rb
+++ b/spec/rubyspec/core/kernel/public_method_spec.rb
@@ -18,9 +18,9 @@ describe "Kernel#public_method" do
 
   it "raises a NameError when called on a protected method" do
     @obj.send(:protected_method).should == :protected_method
-    lambda do
+    lambda {
       @obj.public_method(:protected_method)
-     end.should raise_error(NameError)
+    }.should raise_error(NameError)
   end
 
   it "raises a NameError if we only repond_to_missing? method, true" do
diff --git a/spec/rubyspec/core/kernel/singleton_method_spec.rb b/spec/rubyspec/core/kernel/singleton_method_spec.rb
new file mode 100644
index 0000000000..77022b40c2
--- /dev/null
+++ b/spec/rubyspec/core/kernel/singleton_method_spec.rb
@@ -0,0 +1,41 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "Kernel#singleton_method" do
+  it "find a method defined on the singleton class" do
+    obj = Object.new
+    def obj.foo; end
+    obj.singleton_method(:foo).should be_an_instance_of(Method)
+  end
+
+  it "returns a Method which can be called" do
+    obj = Object.new
+    def obj.foo; 42; end
+    obj.singleton_method(:foo).call.should == 42
+  end
+
+  it "only looks at singleton methods and not at methods in the class" do
+    klass = Class.new do
+      def foo
+        42
+      end
+    end
+    obj = klass.new
+    obj.foo.should == 42
+    -> {
+      obj.singleton_method(:foo)
+    }.should raise_error(NameError) { |e|
+      # a NameError and not a NoMethodError
+      e.class.should == NameError
+    }
+  end
+
+  it "raises a NameError if there is no such method" do
+    obj = Object.new
+    -> {
+      obj.singleton_method(:not_existing)
+    }.should raise_error(NameError) { |e|
+      # a NameError and not a NoMethodError
+      e.class.should == NameError
+    }
+  end
+end
diff --git a/spec/rubyspec/core/marshal/dump_spec.rb b/spec/rubyspec/core/marshal/dump_spec.rb
index 6b369f9bb0..393b8a93f4 100644
--- a/spec/rubyspec/core/marshal/dump_spec.rb
+++ b/spec/rubyspec/core/marshal/dump_spec.rb
@@ -415,6 +415,15 @@ describe "Marshal.dump" do
       load = Marshal.load(dump)
       load.should == (1...2)
     end
+
+    it "dumps a Range with extra instance variables" do
+      range = (1...3)
+      range.instance_variable_set :@foo, 42
+      dump = Marshal.dump(range)
+      load = Marshal.load(dump)
+      load.should == range
+      load.instance_variable_get(:@foo).should == 42
+    end
   end
 
   describe "with a Time" do
diff --git a/spec/rubyspec/core/matchdata/named_captures_spec.rb b/spec/rubyspec/core/matchdata/named_captures_spec.rb
new file mode 100644
index 0000000000..1ab3152262
--- /dev/null
+++ b/spec/rubyspec/core/matchdata/named_captures_spec.rb
@@ -0,0 +1,13 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+ruby_version_is '2.4' do
+  describe 'MatchData#named_captures' do
+    it 'returns a Hash that has captured name and the matched string pairs' do
+      /(?<a>.)(?<b>.)?/.match('0').named_captures.should == { 'a' => '0', 'b' => nil }
+    end
+
+    it 'prefers later captures' do
+      /\A(?<a>.)(?<b>.)(?<b>.)(?<a>.)\z/.match('0123').named_captures.should == { 'a' => '3', 'b' => '2' }
+    end
+  end
+end
\ No newline at end of file
diff --git a/spec/rubyspec/core/matchdata/values_at_spec.rb b/spec/rubyspec/core/matchdata/values_at_spec.rb
index 8d786246f9..0b2727e001 100644
--- a/spec/rubyspec/core/matchdata/values_at_spec.rb
+++ b/spec/rubyspec/core/matchdata/values_at_spec.rb
@@ -10,4 +10,14 @@ describe "MatchData#values_at" do
       /(.)(.)(\d+)(\d)/.match("THX1138: The Movie").values_at(2..4, 0..1).should == ["X", "113", "8", "HX1138", "H"]
     end
   end
+
+  ruby_version_is '2.4' do
+    it 'slices captures with the given names' do
+      /(?<a>.)(?<b>.)(?<c>.)/.match('012').values_at(:c, :a).should == ['2', '0']
+    end
+
+    it 'takes names and indices' do
+      /\A(?<a>.)(?<b>.)\z/.match('01').values_at(0, 1, 2, :a, :b).should == ['01', '0', '1', '0', '1']
+    end
+  end
 end
diff --git a/spec/rubyspec/core/module/autoload_spec.rb b/spec/rubyspec/core/module/autoload_spec.rb
index b479d049bb..9116ddf0a9 100644
--- a/spec/rubyspec/core/module/autoload_spec.rb
+++ b/spec/rubyspec/core/module/autoload_spec.rb
@@ -414,7 +414,7 @@ describe "Module#autoload" do
         mod_names = []
         mod_count.times do |i|
           mod_name = :"Mod#{i}"
-          autoload mod_name, autoload_path
+          Object.autoload mod_name, autoload_path
           mod_names << mod_name
         end
 
diff --git a/spec/rubyspec/core/module/module_function_spec.rb b/spec/rubyspec/core/module/module_function_spec.rb
index 8ced48c505..61509c8d03 100644
--- a/spec/rubyspec/core/module/module_function_spec.rb
+++ b/spec/rubyspec/core/module/module_function_spec.rb
@@ -151,10 +151,10 @@ end
 describe "Module#module_function as a toggle (no arguments) in a Module body" do
   it "makes any subsequently defined methods module functions with the normal semantics" do
     m = Module.new {
-          module_function
-            def test1() end
-            def test2() end
-        }
+      module_function
+      def test1() end
+      def test2() end
+    }
 
     m.respond_to?(:test1).should == true
     m.respond_to?(:test2).should == true
@@ -172,12 +172,12 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
   it "stops creating module functions if the body encounters another toggle " \
      "like public/protected/private without arguments" do
     m = Module.new {
-          module_function
-            def test1() end
-            def test2() end
-          public
-            def test3() end
-        }
+      module_function
+      def test1() end
+      def test2() end
+      public
+      def test3() end
+    }
 
     m.respond_to?(:test1).should == true
     m.respond_to?(:test2).should == true
@@ -187,16 +187,13 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
   it "does not stop creating module functions if the body encounters " \
      "public/protected/private WITH arguments" do
     m = Module.new {
-          def foo() end
-
-          module_function
-            def test1() end
-            def test2() end
-
-            public :foo
-
-            def test3() end
-        }
+      def foo() end
+      module_function
+      def test1() end
+      def test2() end
+      public :foo
+      def test3() end
+    }
 
     m.respond_to?(:test1).should == true
     m.respond_to?(:test2).should == true
@@ -205,11 +202,10 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
 
   it "does not affect module_evaled method definitions also if outside the eval itself" do
     m = Module.new {
-          module_function
-
-          module_eval { def test1() end }
-          module_eval " def test2() end "
-        }
+      module_function
+      module_eval { def test1() end }
+      module_eval " def test2() end "
+    }
 
     m.respond_to?(:test1).should == false
     m.respond_to?(:test2).should == false
@@ -217,11 +213,10 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
 
   it "has no effect if inside a module_eval if the definitions are outside of it" do
     m = Module.new {
-          module_eval { module_function }
-
-          def test1() end
-          def test2() end
-        }
+      module_eval { module_function }
+      def test1() end
+      def test2() end
+    }
 
     m.respond_to?(:test1).should == false
     m.respond_to?(:test2).should == false
@@ -229,13 +224,12 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
 
   it "functions normally if both toggle and definitions inside a module_eval" do
     m = Module.new {
-          module_eval {
-            module_function
-
-            def test1() end
-            def test2() end
-          }
-        }
+      module_eval {
+        module_function
+        def test1() end
+        def test2() end
+      }
+    }
 
     m.respond_to?(:test1).should == true
     m.respond_to?(:test2).should == true
@@ -243,10 +237,9 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
 
   it "affects evaled method definitions also even when outside the eval itself" do
     m = Module.new {
-          module_function
-
-          eval "def test1() end"
-        }
+      module_function
+      eval "def test1() end"
+    }
 
     m.respond_to?(:test1).should == true
   end
@@ -254,7 +247,6 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
   it "doesn't affect definitions when inside an eval even if the definitions are outside of it" do
     m = Module.new {
       eval "module_function"
-
       def test1() end
     }
 
@@ -263,13 +255,13 @@ describe "Module#module_function as a toggle (no arguments) in a Module body" do
 
   it "functions normally if both toggle and definitions inside a eval" do
     m = Module.new {
-          eval <<-CODE
-            module_function
+      eval <<-CODE
+        module_function
 
-            def test1() end
-            def test2() end
-          CODE
-        }
+        def test1() end
+        def test2() end
+      CODE
+    }
 
     m.respond_to?(:test1).should == true
     m.respond_to?(:test2).should == true
diff --git a/spec/rubyspec/core/module/shared/set_visibility.rb b/spec/rubyspec/core/module/shared/set_visibility.rb
index 45eedc13fa..c39d59e05d 100644
--- a/spec/rubyspec/core/module/shared/set_visibility.rb
+++ b/spec/rubyspec/core/module/shared/set_visibility.rb
@@ -9,11 +9,11 @@ describe :set_visibility, shared: true do
     it "sets visibility to following method definitions" do
       visibility = @method
       mod = Module.new {
-            send visibility
+        send visibility
 
-            def test1() end
-            def test2() end
-          }
+        def test1() end
+        def test2() end
+      }
 
       mod.should send(:"have_#{@method}_instance_method", :test1, false)
       mod.should send(:"have_#{@method}_instance_method", :test2, false)
@@ -23,11 +23,11 @@ describe :set_visibility, shared: true do
       visibility = @method
       new_visibility = nil
       mod = Module.new {
-            send visibility
-            new_visibility = [:protected, :private].find {|vis| vis != visibility }
-            send new_visibility
-            def test1() end
-          }
+        send visibility
+        new_visibility = [:protected, :private].find {|vis| vis != visibility }
+        send new_visibility
+        def test1() end
+      }
 
       mod.should send(:"have_#{new_visibility}_instance_method", :test1, false)
     end
@@ -35,11 +35,11 @@ describe :set_visibility, shared: true do
     it "continues setting visibility if the body encounters other visibility setters with arguments" do
       visibility = @method
       mod = Module.new {
-            send visibility
-            def test1() end
-            send([:protected, :private].find {|vis| vis != visibility }, :test1)
-            def test2() end
-          }
+        send visibility
+        def test1() end
+        send([:protected, :private].find {|vis| vis != visibility }, :test1)
+        def test2() end
+      }
 
       mod.should send(:"have_#{@method}_instance_method", :test2, false)
     end
@@ -47,11 +47,11 @@ describe :set_visibility, shared: true do
     it "does not affect module_evaled method definitions when itself is outside the eval" do
       visibility = @method
       mod = Module.new {
-            send visibility
+        send visibility
 
-            module_eval { def test1() end }
-            module_eval " def test2() end "
-          }
+        module_eval { def test1() end }
+        module_eval " def test2() end "
+      }
 
       mod.should have_public_instance_method(:test1, false)
       mod.should have_public_instance_method(:test2, false)
@@ -60,10 +60,10 @@ describe :set_visibility, shared: true do
     it "does not affect outside method definitions when itself is inside a module_eval" do
       visibility = @method
       mod = Module.new {
-            module_eval { send visibility }
+        module_eval { send visibility }
 
-            def test1() end
-          }
+        def test1() end
+      }
 
       mod.should have_public_instance_method(:test1, false)
     end
@@ -71,12 +71,12 @@ describe :set_visibility, shared: true do
     it "affects normally if itself and method definitions are inside a module_eval" do
       visibility = @method
       mod = Module.new {
-            module_eval {
-              send visibility
+        module_eval {
+          send visibility
 
-              def test1() end
-            }
-          }
+          def test1() end
+        }
+      }
 
       mod.should send(:"have_#{@method}_instance_method", :test1, false)
     end
@@ -85,11 +85,11 @@ describe :set_visibility, shared: true do
       visibility = @method
       initialized_visibility = [:public, :protected, :private].find {|sym| sym != visibility }
       mod = Module.new {
-            send initialized_visibility
-            eval visibility.to_s
+        send initialized_visibility
+        eval visibility.to_s
 
-            def test1() end
-          }
+        def test1() end
+      }
 
       mod.should send(:"have_#{initialized_visibility}_instance_method", :test1, false)
     end
@@ -97,10 +97,10 @@ describe :set_visibility, shared: true do
     it "affects evaled method definitions when itself is outside the eval" do
       visibility = @method
       mod = Module.new {
-            send visibility
+        send visibility
 
-            eval "def test1() end"
-          }
+        eval "def test1() end"
+      }
 
       mod.should send(:"have_#{@method}_instance_method", :test1, false)
     end
@@ -108,12 +108,12 @@ describe :set_visibility, shared: true do
     it "affects normally if itself and following method definitions are inside a eval" do
       visibility = @method
       mod = Module.new {
-            eval <<-CODE
-              #{visibility}
+        eval <<-CODE
+          #{visibility}
 
-              def test1() end
-            CODE
-          }
+          def test1() end
+        CODE
+      }
 
       mod.should send(:"have_#{@method}_instance_method", :test1, false)
     end
@@ -122,11 +122,11 @@ describe :set_visibility, shared: true do
       it "sets the visibility outside the closure" do
         visibility = @method
         mod = Module.new {
-              1.times {
-                send visibility
-              }
-              def test1() end
-            }
+          1.times {
+            send visibility
+          }
+          def test1() end
+        }
 
         mod.should send(:"have_#{@method}_instance_method", :test1, false)
       end
diff --git a/spec/rubyspec/core/nil/nilclass_spec.rb b/spec/rubyspec/core/nil/nilclass_spec.rb
new file mode 100644
index 0000000000..3f28cde0bd
--- /dev/null
+++ b/spec/rubyspec/core/nil/nilclass_spec.rb
@@ -0,0 +1,15 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "NilClass" do
+  it ".allocate raises a TypeError" do
+    lambda do
+      NilClass.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      NilClass.new
+    end.should raise_error(NoMethodError)
+  end
+end
diff --git a/spec/rubyspec/core/numeric/shared/step.rb b/spec/rubyspec/core/numeric/shared/step.rb
index 6898a9ff3c..3072830534 100644
--- a/spec/rubyspec/core/numeric/shared/step.rb
+++ b/spec/rubyspec/core/numeric/shared/step.rb
@@ -407,6 +407,18 @@ describe :numeric_step, :shared => true do
             end
           end
         end
+
+        describe "when stop is not passed" do
+          it "returns infinity_value" do
+            1.send(@method, *@step_args.call()).size.should == infinity_value
+          end
+        end
+
+        describe "when stop is nil" do
+          it "returns infinity_value" do
+            1.send(@method, *@step_args.call(nil, 5)).size.should == infinity_value
+          end
+        end
       end
     end
   end
diff --git a/spec/rubyspec/core/process/fixtures/common.rb b/spec/rubyspec/core/process/fixtures/common.rb
index 046efa5396..bdbf1e654b 100644
--- a/spec/rubyspec/core/process/fixtures/common.rb
+++ b/spec/rubyspec/core/process/fixtures/common.rb
@@ -1,4 +1,17 @@
 module ProcessSpecs
+  def self.use_system_ruby(context)
+    if defined?(MSpecScript::SYSTEM_RUBY)
+      context.send(:before, :all) do
+        @ruby = ::RUBY_EXE
+        Object.const_set(:RUBY_EXE, MSpecScript::SYSTEM_RUBY)
+      end
+
+      context.send(:after, :all) do
+        Object.const_set(:RUBY_EXE, @ruby)
+      end
+    end
+  end
+
   class Daemonizer
     attr_reader :input, :data
 
@@ -55,13 +68,6 @@ module ProcessSpecs
     end
 
     def wait_on_result
-      # Ensure the process exits
-      begin
-        Process.kill :TERM, pid if pid
-      rescue Errno::ESRCH
-        # Ignore the process not existing
-      end
-
       @thread.join
     end
 
diff --git a/spec/rubyspec/core/process/fixtures/env.rb b/spec/rubyspec/core/process/fixtures/env.rb
deleted file mode 100644
index 2d626caf26..0000000000
--- a/spec/rubyspec/core/process/fixtures/env.rb
+++ /dev/null
@@ -1 +0,0 @@
-File.write ARGV[0], ENV["FOO"]
diff --git a/spec/rubyspec/core/process/fixtures/print.rb b/spec/rubyspec/core/process/fixtures/print.rb
deleted file mode 100644
index 3697f7dc93..0000000000
--- a/spec/rubyspec/core/process/fixtures/print.rb
+++ /dev/null
@@ -1 +0,0 @@
-print :glark
diff --git a/spec/rubyspec/core/process/kill_spec.rb b/spec/rubyspec/core/process/kill_spec.rb
index c7b0e2a129..4316daf374 100644
--- a/spec/rubyspec/core/process/kill_spec.rb
+++ b/spec/rubyspec/core/process/kill_spec.rb
@@ -2,6 +2,8 @@ require File.expand_path('../../../spec_helper', __FILE__)
 require File.expand_path('../fixtures/common', __FILE__)
 
 describe "Process.kill" do
+  ProcessSpecs.use_system_ruby(self)
+
   before :each do
     @pid = Process.pid
   end
@@ -22,7 +24,7 @@ describe "Process.kill" do
   end
 
   it "raises Errno::ESRCH if the process does not exist" do
-    pid = Process.spawn(ruby_cmd("sleep 10"))
+    pid = Process.spawn(*ruby_exe, "-e", "sleep 10")
     Process.kill("SIGKILL", pid)
     Process.wait(pid)
     lambda {
@@ -33,6 +35,8 @@ end
 
 platform_is_not :windows do
   describe "Process.kill" do
+    ProcessSpecs.use_system_ruby(self)
+
     before :each do
       @sp = ProcessSpecs::Signalizer.new
     end
@@ -73,6 +77,8 @@ platform_is_not :windows do
   end
 
   describe "Process.kill" do
+    ProcessSpecs.use_system_ruby(self)
+
     before :each do
       @sp1 = ProcessSpecs::Signalizer.new
       @sp2 = ProcessSpecs::Signalizer.new
@@ -95,57 +101,27 @@ platform_is_not :windows do
   end
 
   describe "Process.kill" do
-    before :each do
-      @sp = ProcessSpecs::Signalizer.new "self"
-    end
-
     after :each do
-      @sp.cleanup
+      @sp.cleanup if @sp
     end
 
     it "signals the process group if the PID is zero" do
+      @sp = ProcessSpecs::Signalizer.new "self"
       @sp.result.should == "signaled"
     end
-  end
-
-  describe "Process.kill" do
-    before :each do
-      @sp = ProcessSpecs::Signalizer.new "group_numeric"
-    end
-
-    after :each do
-      @sp.cleanup
-    end
 
     it "signals the process group if the signal number is negative" do
+      @sp = ProcessSpecs::Signalizer.new "group_numeric"
       @sp.result.should == "signaled"
     end
-  end
-
-  describe "Process.kill" do
-    before :each do
-      @sp = ProcessSpecs::Signalizer.new "group_short_string"
-    end
-
-    after :each do
-      @sp.cleanup
-    end
 
     it "signals the process group if the short signal name starts with a minus sign" do
+      @sp = ProcessSpecs::Signalizer.new "group_short_string"
       @sp.result.should == "signaled"
     end
-  end
-
-  describe "Process.kill" do
-    before :each do
-      @sp = ProcessSpecs::Signalizer.new "group_full_string"
-    end
-
-    after :each do
-      @sp.cleanup
-    end
 
     it "signals the process group if the full signal name starts with a minus sign" do
+      @sp = ProcessSpecs::Signalizer.new "group_full_string"
       @sp.result.should == "signaled"
     end
   end
diff --git a/spec/rubyspec/core/process/spawn_spec.rb b/spec/rubyspec/core/process/spawn_spec.rb
index 66b5c5e402..330ec8fcd8 100644
--- a/spec/rubyspec/core/process/spawn_spec.rb
+++ b/spec/rubyspec/core/process/spawn_spec.rb
@@ -1,4 +1,5 @@
 require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/common', __FILE__)
 
 newline = "\n"
 platform_is :windows do
@@ -31,8 +32,14 @@ describe :process_spawn_does_not_close_std_streams, shared: true do
 end
 
 describe "Process.spawn" do
+  ProcessSpecs.use_system_ruby(self)
+
   before :each do
     @name = tmp("process_spawn.txt")
+    @var = "$FOO"
+    platform_is :windows do
+      @var = "%FOO%"
+    end
   end
 
   after :each do
@@ -44,14 +51,14 @@ describe "Process.spawn" do
   end
 
   it "returns the process ID of the new process as a Fixnum" do
-    pid = Process.spawn(ruby_cmd("exit"))
+    pid = Process.spawn(*ruby_exe, "-e", "exit")
     Process.wait pid
     pid.should be_an_instance_of(Fixnum)
   end
 
   it "returns immediately" do
     start = Time.now
-    pid = Process.spawn(ruby_cmd("sleep 10"))
+    pid = Process.spawn(*ruby_exe, "-e", "sleep 10")
     (Time.now - start).should < 5
     Process.kill :KILL, pid
     Process.wait pid
@@ -196,52 +203,57 @@ describe "Process.spawn" do
   end
 
   it "sets environment variables in the child environment" do
-    Process.wait Process.spawn({"FOO" => "BAR"}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
-    File.read(@name).should == "BAR"
+    Process.wait Process.spawn({"FOO" => "BAR"}, "echo #{@var}>#{@name}")
+    File.read(@name).should == "BAR\n"
   end
 
   it "unsets environment variables whose value is nil" do
     ENV["FOO"] = "BAR"
-    Process.wait Process.spawn({"FOO" => nil}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
-    File.read(@name).should == ""
+    Process.wait Process.spawn({"FOO" => nil}, "echo #{@var}>#{@name}")
+    expected = "\n"
+    platform_is :windows do
+      # Windows does not expand the variable if it is unset
+      expected = "#{@var}\n"
+    end
+    File.read(@name).should == expected
   end
 
   it "calls #to_hash to convert the environment" do
     o = mock("to_hash")
     o.should_receive(:to_hash).and_return({"FOO" => "BAR"})
-    Process.wait Process.spawn(o, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
-    File.read(@name).should == "BAR"
+    Process.wait Process.spawn(o, "echo #{@var}>#{@name}")
+    File.read(@name).should == "BAR\n"
   end
 
   it "calls #to_str to convert the environment keys" do
     o = mock("to_str")
     o.should_receive(:to_str).and_return("FOO")
-    Process.wait Process.spawn({o => "BAR"}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
-    File.read(@name).should == "BAR"
+    Process.wait Process.spawn({o => "BAR"}, "echo #{@var}>#{@name}")
+    File.read(@name).should == "BAR\n"
   end
 
   it "calls #to_str to convert the environment values" do
     o = mock("to_str")
     o.should_receive(:to_str).and_return("BAR")
-    Process.wait Process.spawn({"FOO" => o}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
-    File.read(@name).should == "BAR"
+    Process.wait Process.spawn({"FOO" => o}, "echo #{@var}>#{@name}")
+    File.read(@name).should == "BAR\n"
   end
 
   it "raises an ArgumentError if an environment key includes an equals sign" do
     lambda do
-      Process.spawn({"FOO=" => "BAR"}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
+      Process.spawn({"FOO=" => "BAR"}, "echo #{@var}>#{@name}")
     end.should raise_error(ArgumentError)
   end
 
   it "raises an ArgumentError if an environment key includes a null byte" do
     lambda do
-      Process.spawn({"\000" => "BAR"}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
+      Process.spawn({"\000" => "BAR"}, "echo #{@var}>#{@name}")
     end.should raise_error(ArgumentError)
   end
 
   it "raises an ArgumentError if an environment value includes a null byte" do
     lambda do
-      Process.spawn({"FOO" => "\000"}, ruby_cmd(fixture(__FILE__, "env.rb"), args: @name))
+      Process.spawn({"FOO" => "\000"}, "echo #{@var}>#{@name}")
     end.should raise_error(ArgumentError)
   end
 
@@ -252,7 +264,7 @@ describe "Process.spawn" do
       "PATH" => ENV["PATH"],
       "HOME" => ENV["HOME"]
     }
-    @common_env_spawn_args = [@minimal_env, ruby_cmd(fixture(__FILE__, "env.rb"), options: "--disable-gems", args: @name)]
+    @common_env_spawn_args = [@minimal_env, "echo #{@var}>#{@name}"]
   end
 
   platform_is_not :windows do
@@ -260,7 +272,7 @@ describe "Process.spawn" do
       ENV["FOO"] = "BAR"
       Process.wait Process.spawn(*@common_env_spawn_args, unsetenv_others: true)
       $?.success?.should be_true
-      File.read(@name).should == ""
+      File.read(@name).should == "\n"
     end
   end
 
@@ -268,15 +280,15 @@ describe "Process.spawn" do
     ENV["FOO"] = "BAR"
     Process.wait Process.spawn(*@common_env_spawn_args, unsetenv_others: false)
     $?.success?.should be_true
-    File.read(@name).should == "BAR"
+    File.read(@name).should == "BAR\n"
   end
 
   platform_is_not :windows do
     it "does not unset environment variables included in the environment hash" do
       env = @minimal_env.merge({"FOO" => "BAR"})
-      Process.wait Process.spawn(env, ruby_cmd(fixture(__FILE__, "env.rb"), options: "--disable-gems", args: @name), unsetenv_others: true)
+      Process.wait Process.spawn(env, "echo #{@var}>#{@name}", unsetenv_others: true)
       $?.success?.should be_true
-      File.read(@name).should == "BAR"
+      File.read(@name).should == "BAR\n"
     end
   end
 
@@ -400,55 +412,55 @@ describe "Process.spawn" do
   it "redirects STDOUT to the given file descriptior if out: Fixnum" do
     File.open(@name, 'w') do |file|
       lambda do
-        Process.wait Process.spawn(ruby_cmd(fixture(__FILE__, "print.rb")), out: file.fileno)
-      end.should output_to_fd("glark", file)
+        Process.wait Process.spawn("echo glark", out: file.fileno)
+      end.should output_to_fd("glark\n", file)
     end
   end
 
   it "redirects STDOUT to the given file if out: IO" do
     File.open(@name, 'w') do |file|
       lambda do
-        Process.wait Process.spawn(ruby_cmd(fixture(__FILE__, "print.rb")), out: file)
-      end.should output_to_fd("glark", file)
+        Process.wait Process.spawn("echo glark", out: file)
+      end.should output_to_fd("glark\n", file)
     end
   end
 
   it "redirects STDOUT to the given file if out: String" do
-    Process.wait Process.spawn(ruby_cmd(fixture(__FILE__, "print.rb")), out: @name)
-    File.read(@name).should == "glark"
+    Process.wait Process.spawn("echo glark", out: @name)
+    File.read(@name).should == "glark\n"
   end
 
   it "redirects STDOUT to the given file if out: [String name, String mode]" do
-    Process.wait Process.spawn(ruby_cmd(fixture(__FILE__, "print.rb")), out: [@name, 'w'])
-    File.read(@name).should == "glark"
+    Process.wait Process.spawn("echo glark", out: [@name, 'w'])
+    File.read(@name).should == "glark\n"
   end
 
   it "redirects STDERR to the given file descriptior if err: Fixnum" do
     File.open(@name, 'w') do |file|
       lambda do
-        Process.wait Process.spawn(ruby_cmd("STDERR.print :glark"), err: file.fileno)
-      end.should output_to_fd("glark", file)
+        Process.wait Process.spawn("echo glark>&2", err: file.fileno)
+      end.should output_to_fd("glark\n", file)
     end
   end
 
   it "redirects STDERR to the given file descriptor if err: IO" do
     File.open(@name, 'w') do |file|
       lambda do
-        Process.wait Process.spawn(ruby_cmd("STDERR.print :glark"), err: file)
-      end.should output_to_fd("glark", file)
+        Process.wait Process.spawn("echo glark>&2", err: file)
+      end.should output_to_fd("glark\n", file)
     end
   end
 
   it "redirects STDERR to the given file if err: String" do
-    Process.wait Process.spawn(ruby_cmd("STDERR.print :glark"), err: @name)
-    File.read(@name).should == "glark"
+    Process.wait Process.spawn("echo glark>&2", err: @name)
+    File.read(@name).should == "glark\n"
   end
 
   it "redirects STDERR to child STDOUT if :err => [:child, :out]" do
     File.open(@name, 'w') do |file|
       lambda do
-        Process.wait Process.spawn(ruby_cmd("STDERR.print :glark"), :out => file, :err => [:child, :out])
-      end.should output_to_fd("glark", file)
+        Process.wait Process.spawn("echo glark>&2", :out => file, :err => [:child, :out])
+      end.should output_to_fd("glark\n", file)
     end
   end
 
diff --git a/spec/rubyspec/core/process/wait_spec.rb b/spec/rubyspec/core/process/wait_spec.rb
index dca43140fd..8111621695 100644
--- a/spec/rubyspec/core/process/wait_spec.rb
+++ b/spec/rubyspec/core/process/wait_spec.rb
@@ -1,6 +1,9 @@
 require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/common', __FILE__)
 
 describe "Process.wait" do
+  ProcessSpecs.use_system_ruby(self)
+
   before :all do
     begin
       leaked = Process.waitall
diff --git a/spec/rubyspec/core/regexp/encoding_spec.rb b/spec/rubyspec/core/regexp/encoding_spec.rb
index 6ce1ada337..c30519c9d7 100644
--- a/spec/rubyspec/core/regexp/encoding_spec.rb
+++ b/spec/rubyspec/core/regexp/encoding_spec.rb
@@ -15,7 +15,7 @@ describe "Regexp#encoding" do
   end
 
   it "returns ASCII-8BIT if the 'n' modifier is supplied and non-US-ASCII characters are present" do
-    /#{}\xc2\xa1/n.encoding.should == Encoding::ASCII_8BIT
+    /\xc2\xa1/n.encoding.should == Encoding::ASCII_8BIT
   end
 
   it "defaults to UTF-8 if \\u escapes appear" do
diff --git a/spec/rubyspec/core/string/encoding_spec.rb b/spec/rubyspec/core/string/encoding_spec.rb
index a07032b041..9c655757a8 100644
--- a/spec/rubyspec/core/string/encoding_spec.rb
+++ b/spec/rubyspec/core/string/encoding_spec.rb
@@ -133,7 +133,7 @@ with_feature :encoding do
       str += [0xDF].pack('C')
       str.ascii_only?.should be_false
       str.encoding.should == Encoding::ASCII_8BIT
-     end
+    end
 
     # TODO: Deal with case when the byte in question isn't valid in the source
     # encoding?
diff --git a/spec/rubyspec/core/symbol/symbol_spec.rb b/spec/rubyspec/core/symbol/symbol_spec.rb
index bb95211ba0..af6b46fed3 100644
--- a/spec/rubyspec/core/symbol/symbol_spec.rb
+++ b/spec/rubyspec/core/symbol/symbol_spec.rb
@@ -4,4 +4,16 @@ describe "Symbol" do
   it "includes Comparable" do
     Symbol.include?(Comparable).should == true
   end
+
+  it ".allocate raises a TypeError" do
+    lambda do
+      Symbol.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      Symbol.new
+    end.should raise_error(NoMethodError)
+  end
 end
diff --git a/spec/rubyspec/core/time/dup_spec.rb b/spec/rubyspec/core/time/dup_spec.rb
index 16aab04200..b32ce96d44 100644
--- a/spec/rubyspec/core/time/dup_spec.rb
+++ b/spec/rubyspec/core/time/dup_spec.rb
@@ -36,4 +36,11 @@ describe "Time#dup" do
     t.dup.should be_an_instance_of(c)
     t.dup.should_not be_an_instance_of(Time)
   end
+
+  it "does not copy frozen status from the original" do
+    t = Time.now
+    t.freeze
+    t2 = t.dup
+    t2.frozen?.should be_false
+  end
 end
diff --git a/spec/rubyspec/core/time/localtime_spec.rb b/spec/rubyspec/core/time/localtime_spec.rb
index 8144fd67e6..6f682b0b34 100644
--- a/spec/rubyspec/core/time/localtime_spec.rb
+++ b/spec/rubyspec/core/time/localtime_spec.rb
@@ -22,6 +22,20 @@ describe "Time#localtime" do
     t.utc_offset.should == 3630
   end
 
+  describe "on a frozen time" do
+    it "does not raise an error if already in the right time zone" do
+      time = Time.now
+      time.freeze
+      time.localtime.should equal(time)
+    end
+
+    it "raises a RuntimeError if the time has a different time zone" do
+      time = Time.gm(2007, 1, 9, 12, 0, 0)
+      time.freeze
+      lambda { time.localtime }.should raise_error(RuntimeError)
+    end
+  end
+
   describe "with an argument that responds to #to_int" do
     it "coerces using #to_int" do
       o = mock('integer')
diff --git a/spec/rubyspec/core/time/shared/gmtime.rb b/spec/rubyspec/core/time/shared/gmtime.rb
index a1b4b88418..e684a1fd95 100644
--- a/spec/rubyspec/core/time/shared/gmtime.rb
+++ b/spec/rubyspec/core/time/shared/gmtime.rb
@@ -1,5 +1,5 @@
 describe :time_gmtime, shared: true do
-  it "returns the utc representation of time" do
+  it "converts self to UTC, modifying the receiver" do
     # Testing with America/Regina here because it doesn't have DST.
     with_timezone("CST", -6) do
       t = Time.local(2007, 1, 9, 6, 0, 0)
@@ -7,4 +7,27 @@ describe :time_gmtime, shared: true do
       t.should == Time.gm(2007, 1, 9, 12, 0, 0)
     end
   end
+
+  it "returns self" do
+    with_timezone("CST", -6) do
+      t = Time.local(2007, 1, 9, 12, 0, 0)
+      t.send(@method).should equal(t)
+    end
+  end
+
+  describe "on a frozen time" do
+    it "does not raise an error if already in UTC" do
+      time = Time.gm(2007, 1, 9, 12, 0, 0)
+      time.freeze
+      time.send(@method).should equal(time)
+    end
+
+    it "raises a RuntimeError if the time is not UTC" do
+      with_timezone("CST", -6) do
+        time = Time.now
+        time.freeze
+        lambda { time.send(@method) }.should raise_error(RuntimeError)
+      end
+    end
+  end
 end
diff --git a/spec/rubyspec/core/true/trueclass_spec.rb b/spec/rubyspec/core/true/trueclass_spec.rb
new file mode 100644
index 0000000000..8837117d71
--- /dev/null
+++ b/spec/rubyspec/core/true/trueclass_spec.rb
@@ -0,0 +1,15 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "TrueClass" do
+  it ".allocate raises a TypeError" do
+    lambda do
+      TrueClass.allocate
+    end.should raise_error(TypeError)
+  end
+
+  it ".new is undefined" do
+    lambda do
+      TrueClass.new
+    end.should raise_error(NoMethodError)
+  end
+end