Move spec/rubyspec to spec/ruby for consistency

* Other ruby implementations use the spec/ruby directory.
  [Misc #13792] [ruby-core:82287]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

spec/ruby/core/string/shared/chars.rb

@@ -0,0 +1,82 @@
+# -*- encoding: utf-8 -*-
+require File.expand_path('../../../../spec_helper', __FILE__)
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :string_chars, shared: true do
+  it "passes each char in self to the given block" do
+    a = []
+    "hello".send(@method) { |c| a << c }
+    a.should == ['h', 'e', 'l', 'l', 'o']
+  end
+
+  it "returns self" do
+    s = StringSpecs::MyString.new "hello"
+    s.send(@method){}.should equal(s)
+  end
+
+
+  it "is unicode aware" do
+    "\303\207\342\210\202\303\251\306\222g".send(@method).to_a.should ==
+      ["\303\207", "\342\210\202", "\303\251", "\306\222", "g"]
+  end
+
+  with_feature :encoding do
+    it "returns characters in the same encoding as self" do
+      "&%".force_encoding('Shift_JIS').send(@method).to_a.all? {|c| c.encoding.name.should == 'Shift_JIS'}
+      "&%".encode('ASCII-8BIT').send(@method).to_a.all? {|c| c.encoding.name.should == 'ASCII-8BIT'}
+    end
+
+    it "works with multibyte characters" do
+      s = "\u{8987}".force_encoding("UTF-8")
+      s.bytesize.should == 3
+      s.send(@method).to_a.should == [s]
+    end
+
+    it "works if the String's contents is invalid for its encoding" do
+      xA4 = [0xA4].pack('C')
+      xA4.force_encoding('UTF-8')
+      xA4.valid_encoding?.should be_false
+      xA4.send(@method).to_a.should == [xA4.force_encoding("UTF-8")]
+    end
+
+    it "returns a different character if the String is transcoded" do
+      s = "\u{20AC}".force_encoding('UTF-8')
+      s.encode('UTF-8').send(@method).to_a.should == ["\u{20AC}".force_encoding('UTF-8')]
+      s.encode('iso-8859-15').send(@method).to_a.should == [
+        [0xA4].pack('C').force_encoding('iso-8859-15')]
+      s.encode('iso-8859-15').encode('UTF-8').send(@method).to_a.should == [
+        "\u{20AC}".force_encoding('UTF-8')]
+    end
+
+    it "uses the String's encoding to determine what characters it contains" do
+      s = "\u{24B62}"
+
+      s.force_encoding('UTF-8').send(@method).to_a.should == [
+        s.force_encoding('UTF-8')
+      ]
+      s.force_encoding('BINARY').send(@method).to_a.should == [
+        [0xF0].pack('C').force_encoding('BINARY'),
+        [0xA4].pack('C').force_encoding('BINARY'),
+        [0xAD].pack('C').force_encoding('BINARY'),
+        [0xA2].pack('C').force_encoding('BINARY')
+      ]
+      s.force_encoding('SJIS').send(@method).to_a.should == [
+        [0xF0,0xA4].pack('CC').force_encoding('SJIS'),
+        [0xAD].pack('C').force_encoding('SJIS'),
+        [0xA2].pack('C').force_encoding('SJIS')
+      ]
+    end
+
+    it "taints resulting strings when self is tainted" do
+      str = "hello"
+
+      str.send(@method) do |x|
+        x.tainted?.should == false
+      end
+
+      str.dup.taint.send(@method) do |x|
+        x.tainted?.should == true
+      end
+    end
+  end
+end

spec/ruby/core/string/shared/codepoints.rb

@@ -0,0 +1,56 @@
+# -*- encoding: binary -*-
+describe :string_codepoints, shared: true do
+  it "raises an ArgumentError when self has an invalid encoding and a method is called on the returned Enumerator" do
+    s = "\xDF".force_encoding(Encoding::UTF_8)
+    s.valid_encoding?.should be_false
+    lambda { s.send(@method).to_a }.should raise_error(ArgumentError)
+  end
+
+  it "yields each codepoint to the block if one is given" do
+    codepoints = []
+    "abcd".send(@method) do |codepoint|
+      codepoints << codepoint
+    end
+    codepoints.should == [97, 98, 99, 100]
+  end
+
+  it "raises an ArgumentError if self's encoding is invalid and a block is given" do
+    s = "\xDF".force_encoding(Encoding::UTF_8)
+    s.valid_encoding?.should be_false
+    lambda { s.send(@method) { } }.should raise_error(ArgumentError)
+  end
+
+  it "returns codepoints as Fixnums" do
+    "glark\u{20}".send(@method).to_a.each do |codepoint|
+      codepoint.should be_an_instance_of(Fixnum)
+    end
+  end
+
+  it "returns one codepoint for each character" do
+    s = "\u{9876}\u{28}\u{1987}"
+    s.send(@method).to_a.size.should == s.chars.to_a.size
+  end
+
+  it "works for multibyte characters" do
+    s = "\u{9819}"
+    s.bytesize.should == 3
+    s.send(@method).to_a.should == [38937]
+  end
+
+  it "returns the codepoint corresponding to the character's position in the String's encoding" do
+    "\u{787}".send(@method).to_a.should == [1927]
+  end
+
+  it "round-trips to the original String using Integer#chr" do
+    s = "\u{13}\u{7711}\u{1010}"
+    s2 = ""
+    s.send(@method) {|n| s2 << n.chr(Encoding::UTF_8)}
+    s.should == s2
+  end
+
+  it "is synonomous with #bytes for Strings which are single-byte optimisable" do
+    s = "(){}".encode('ascii')
+    s.ascii_only?.should be_true
+    s.send(@method).to_a.should == s.bytes.to_a
+  end
+end

spec/ruby/core/string/shared/concat.rb

@@ -0,0 +1,160 @@
+describe :string_concat, shared: true do
+  it "concatenates the given argument to self and returns self" do
+    str = 'hello '
+    str.send(@method, 'world').should equal(str)
+    str.should == "hello world"
+  end
+
+  it "converts the given argument to a String using to_str" do
+    obj = mock('world!')
+    obj.should_receive(:to_str).and_return("world!")
+    a = 'hello '.send(@method, obj)
+    a.should == 'hello world!'
+  end
+
+  it "raises a TypeError if the given argument can't be converted to a String" do
+    lambda { 'hello '.send(@method, [])        }.should raise_error(TypeError)
+    lambda { 'hello '.send(@method, mock('x')) }.should raise_error(TypeError)
+  end
+
+  it "raises a RuntimeError when self is frozen" do
+    a = "hello"
+    a.freeze
+
+    lambda { a.send(@method, "")     }.should raise_error(RuntimeError)
+    lambda { a.send(@method, "test") }.should raise_error(RuntimeError)
+  end
+
+  it "returns a String when given a subclass instance" do
+    a = "hello"
+    a.send(@method, StringSpecs::MyString.new(" world"))
+    a.should == "hello world"
+    a.should be_an_instance_of(String)
+  end
+
+  it "returns an instance of same class when called on a subclass" do
+    str = StringSpecs::MyString.new("hello")
+    str.send(@method, " world")
+    str.should == "hello world"
+    str.should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "taints self if other is tainted" do
+    "x".send(@method, "".taint).tainted?.should == true
+    "x".send(@method, "y".taint).tainted?.should == true
+  end
+
+  it "untrusts self if other is untrusted" do
+    "x".send(@method, "".untrust).untrusted?.should == true
+    "x".send(@method, "y".untrust).untrusted?.should == true
+  end
+
+  describe "with Integer" do
+    it "concatencates the argument interpreted as a codepoint" do
+      b = "".send(@method, 33)
+      b.should == "!"
+
+      b.encode!(Encoding::UTF_8)
+      b.send(@method, 0x203D)
+      b.should == "!\u203D"
+    end
+
+    # #5855
+    it "returns a ASCII-8BIT string if self is US-ASCII and the argument is between 128-255 (inclusive)" do
+      a = ("".encode(Encoding::US_ASCII).send(@method, 128))
+      a.encoding.should == Encoding::ASCII_8BIT
+      a.should == 128.chr
+
+      a = ("".encode(Encoding::US_ASCII).send(@method, 255))
+      a.encoding.should == Encoding::ASCII_8BIT
+      a.should == 255.chr
+    end
+
+    it "raises RangeError if the argument is an invalid codepoint for self's encoding" do
+      lambda { "".encode(Encoding::US_ASCII).send(@method, 256) }.should raise_error(RangeError)
+      lambda { "".encode(Encoding::EUC_JP).send(@method, 0x81)  }.should raise_error(RangeError)
+    end
+
+    it "raises RangeError if the argument is negative" do
+      lambda { "".send(@method, -200)          }.should raise_error(RangeError)
+      lambda { "".send(@method, -bignum_value) }.should raise_error(RangeError)
+    end
+
+    it "doesn't call to_int on its argument" do
+      x = mock('x')
+      x.should_not_receive(:to_int)
+
+      lambda { "".send(@method, x) }.should raise_error(TypeError)
+    end
+
+    it "raises a RuntimeError when self is frozen" do
+      a = "hello"
+      a.freeze
+
+      lambda { a.send(@method, 0)  }.should raise_error(RuntimeError)
+      lambda { a.send(@method, 33) }.should raise_error(RuntimeError)
+    end
+  end
+end
+
+describe :string_concat_encoding, shared: true do
+  describe "when self is in an ASCII-incompatible encoding incompatible with the argument's encoding" do
+    it "uses self's encoding if both are empty" do
+      "".encode("UTF-16LE").send(@method, "").encoding.should == Encoding::UTF_16LE
+    end
+
+    it "uses self's encoding if the argument is empty" do
+      "x".encode("UTF-16LE").send(@method, "").encoding.should == Encoding::UTF_16LE
+    end
+
+    it "uses the argument's encoding if self is empty" do
+      "".encode("UTF-16LE").send(@method, "x".encode("UTF-8")).encoding.should == Encoding::UTF_8
+    end
+
+    it "raises Encoding::CompatibilityError if neither are empty" do
+      lambda { "x".encode("UTF-16LE").send(@method, "y".encode("UTF-8")) }.should raise_error(Encoding::CompatibilityError)
+    end
+  end
+
+  describe "when the argument is in an ASCII-incompatible encoding incompatible with self's encoding" do
+    it "uses self's encoding if both are empty" do
+      "".encode("UTF-8").send(@method, "".encode("UTF-16LE")).encoding.should == Encoding::UTF_8
+    end
+
+    it "uses self's encoding if the argument is empty" do
+      "x".encode("UTF-8").send(@method, "".encode("UTF-16LE")).encoding.should == Encoding::UTF_8
+    end
+
+    it "uses the argument's encoding if self is empty" do
+      "".encode("UTF-8").send(@method, "x".encode("UTF-16LE")).encoding.should == Encoding::UTF_16LE
+    end
+
+    it "raises Encoding::CompatibilityError if neither are empty" do
+      lambda { "x".encode("UTF-8").send(@method, "y".encode("UTF-16LE")) }.should raise_error(Encoding::CompatibilityError)
+    end
+  end
+
+  describe "when self and the argument are in different ASCII-compatible encodings" do
+    it "uses self's encoding if both are ASCII-only" do
+      "abc".encode("UTF-8").send(@method, "123".encode("SHIFT_JIS")).encoding.should == Encoding::UTF_8
+    end
+
+    it "uses self's encoding if the argument is ASCII-only" do
+      "\u00E9".encode("UTF-8").send(@method, "123".encode("ISO-8859-1")).encoding.should == Encoding::UTF_8
+    end
+
+    it "uses the argument's encoding if self is ASCII-only" do
+      "abc".encode("UTF-8").send(@method, "\u00E9".encode("ISO-8859-1")).encoding.should == Encoding::ISO_8859_1
+    end
+
+    it "raises Encoding::CompatibilityError if neither are ASCII-only" do
+      lambda { "\u00E9".encode("UTF-8").send(@method, "\u00E9".encode("ISO-8859-1")) }.should raise_error(Encoding::CompatibilityError)
+    end
+  end
+
+  describe "when self is ASCII-8BIT and argument is US-ASCII" do
+    it "uses ASCII-8BIT encoding" do
+      "abc".encode("ASCII-8BIT").send(@method, "123".encode("US-ASCII")).encoding.should == Encoding::ASCII_8BIT
+    end
+  end
+end

spec/ruby/core/string/shared/each_char_without_block.rb

@@ -0,0 +1,26 @@
+# -*- encoding: utf-8 -*-
+require File.expand_path('../../../../spec_helper', __FILE__)
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :string_each_char_without_block, shared: true do
+  describe "when no block is given" do
+    it "returns an enumerator" do
+      enum = "hello".send(@method)
+      enum.should be_an_instance_of(Enumerator)
+      enum.to_a.should == ['h', 'e', 'l', 'l', 'o']
+    end
+
+    describe "returned enumerator" do
+      describe "size" do
+        it "should return the size of the string" do
+          str = "hello"
+          str.send(@method).size.should == str.size
+          str = "ola"
+          str.send(@method).size.should == str.size
+          str = "\303\207\342\210\202\303\251\306\222g"
+          str.send(@method).size.should == str.size
+        end
+      end
+    end
+  end
+end

spec/ruby/core/string/shared/each_codepoint_without_block.rb

@@ -0,0 +1,33 @@
+# -*- encoding: binary -*-
+describe :string_each_codepoint_without_block, shared: true do
+  describe "when no block is given" do
+    it "returns an Enumerator" do
+      "".send(@method).should be_an_instance_of(Enumerator)
+    end
+
+    it "returns an Enumerator even when self has an invalid encoding" do
+      s = "\xDF".force_encoding(Encoding::UTF_8)
+      s.valid_encoding?.should be_false
+      s.send(@method).should be_an_instance_of(Enumerator)
+    end
+
+    describe "returned Enumerator" do
+      describe "size" do
+        it "should return the size of the string" do
+          str = "hello"
+          str.send(@method).size.should == str.size
+          str = "ola"
+          str.send(@method).size.should == str.size
+          str = "\303\207\342\210\202\303\251\306\222g"
+          str.send(@method).size.should == str.size
+        end
+
+        it "should return the size of the string even when the string has an invalid encoding" do
+          s = "\xDF".force_encoding(Encoding::UTF_8)
+          s.valid_encoding?.should be_false
+          s.send(@method).size.should == 1
+        end
+      end
+    end
+  end
+end

spec/ruby/core/string/shared/each_line.rb

@@ -0,0 +1,136 @@
+describe :string_each_line, shared: true do
+  it "splits using default newline separator when none is specified" do
+    a = []
+    "one\ntwo\r\nthree".send(@method) { |s| a << s }
+    a.should == ["one\n", "two\r\n", "three"]
+
+    b = []
+    "hello\n\n\nworld".send(@method) { |s| b << s }
+    b.should == ["hello\n", "\n", "\n", "world"]
+
+    c = []
+    "\n\n\n\n\n".send(@method) {|s| c << s}
+    c.should == ["\n", "\n", "\n", "\n", "\n"]
+  end
+
+  it "splits self using the supplied record separator and passes each substring to the block" do
+    a = []
+    "one\ntwo\r\nthree".send(@method, "\n") { |s| a << s }
+    a.should == ["one\n", "two\r\n", "three"]
+
+    b = []
+    "hello\nworld".send(@method, 'l') { |s| b << s }
+    b.should == [ "hel", "l", "o\nworl", "d" ]
+
+    c = []
+    "hello\n\n\nworld".send(@method, "\n") { |s| c << s }
+    c.should == ["hello\n", "\n", "\n", "world"]
+  end
+
+  it "taints substrings that are passed to the block if self is tainted" do
+    "one\ntwo\r\nthree".taint.send(@method) { |s| s.tainted?.should == true }
+
+    "x.y.".send(@method, ".".taint) { |s| s.tainted?.should == false }
+  end
+
+  it "passes self as a whole to the block if the separator is nil" do
+    a = []
+    "one\ntwo\r\nthree".send(@method, nil) { |s| a << s }
+    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
+
+quarantine! do # Currently fails on Travis
+  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", "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
+  end
+end
+
+  describe "uses $/" do
+    before :each do
+      @before_separator = $/
+    end
+
+    after :each do
+      $/ = @before_separator
+    end
+
+    it "as the separator when none is given" do
+      [
+        "", "x", "x\ny", "x\ry", "x\r\ny", "x\n\r\r\ny",
+        "hello hullo bello"
+      ].each do |str|
+        ["", "llo", "\n", "\r", nil].each do |sep|
+          expected = []
+          str.send(@method, sep) { |x| expected << x }
+
+          $/ = sep
+
+          actual = []
+          str.send(@method) { |x| actual << x }
+
+          actual.should == expected
+        end
+      end
+    end
+  end
+
+  it "yields subclass instances for subclasses" do
+    a = []
+    StringSpecs::MyString.new("hello\nworld").send(@method) { |s| a << s.class }
+    a.should == [StringSpecs::MyString, StringSpecs::MyString]
+  end
+
+  it "returns self" do
+    s = "hello\nworld"
+    (s.send(@method) {}).should equal(s)
+  end
+
+  it "tries to convert the separator to a string using to_str" do
+    separator = mock('l')
+    separator.should_receive(:to_str).and_return("l")
+
+    a = []
+    "hello\nworld".send(@method, separator) { |s| a << s }
+    a.should == [ "hel", "l", "o\nworl", "d" ]
+  end
+
+  it "does not care if the string is modified while substituting" do
+    str = "hello\nworld."
+    out = []
+    str.send(@method){|x| out << x; str[-1] = '!' }.should == "hello\nworld!"
+    out.should == ["hello\n", "world."]
+  end
+
+  it "raises a TypeError when the separator can't be converted to a string" do
+    lambda { "hello world".send(@method, false) {}     }.should raise_error(TypeError)
+    lambda { "hello world".send(@method, mock('x')) {} }.should raise_error(TypeError)
+  end
+
+  it "accepts a string separator" do
+    "hello world".send(@method, ?o).to_a.should == ["hello", " wo", "rld"]
+  end
+
+  it "raises a TypeError when the separator is a symbol" do
+    lambda { "hello world".send(@method, :o).to_a }.should raise_error(TypeError)
+  end
+end

spec/ruby/core/string/shared/each_line_without_block.rb

@@ -0,0 +1,17 @@
+describe :string_each_line_without_block, shared: true do
+  describe "when no block is given" do
+    it "returns an enumerator" do
+      enum = "hello world".send(@method, ' ')
+      enum.should be_an_instance_of(Enumerator)
+      enum.to_a.should == ["hello ", "world"]
+    end
+
+    describe "returned Enumerator" do
+      describe "size" do
+        it "should return nil" do
+          "hello world".send(@method, ' ').size.should == nil
+        end
+      end
+    end
+  end
+end

spec/ruby/core/string/shared/encode.rb

@@ -0,0 +1,247 @@
+# -*- encoding: utf-8 -*-
+describe :string_encode, shared: true do
+  describe "when passed no options" do
+    it "transcodes to Encoding.default_internal when set" do
+      Encoding.default_internal = Encoding::UTF_8
+      str = [0xA4, 0xA2].pack('CC').force_encoding Encoding::EUC_JP
+      str.send(@method).should == "あ"
+    end
+
+    it "transcodes a 7-bit String despite no generic converting being available" do
+      lambda do
+        Encoding::Converter.new Encoding::Emacs_Mule, Encoding::ASCII_8BIT
+      end.should raise_error(Encoding::ConverterNotFoundError)
+
+      Encoding.default_internal = Encoding::Emacs_Mule
+      str = "\x79".force_encoding Encoding::ASCII_8BIT
+
+      str.send(@method).should == "y".force_encoding(Encoding::ASCII_8BIT)
+    end
+
+    it "raises an Encoding::ConverterNotFoundError when no conversion is possible" do
+      Encoding.default_internal = Encoding::Emacs_Mule
+      str = [0x80].pack('C').force_encoding Encoding::ASCII_8BIT
+      lambda { str.send(@method) }.should raise_error(Encoding::ConverterNotFoundError)
+    end
+  end
+
+  describe "when passed to encoding" do
+    it "accepts a String argument" do
+      str = [0xA4, 0xA2].pack('CC').force_encoding Encoding::EUC_JP
+      str.send(@method, "utf-8").should == "あ"
+    end
+
+    it "calls #to_str to convert the object to an Encoding" do
+      enc = mock("string encode encoding")
+      enc.should_receive(:to_str).and_return("utf-8")
+
+      str = [0xA4, 0xA2].pack('CC').force_encoding Encoding::EUC_JP
+      str.send(@method, enc).should == "あ"
+    end
+
+    it "transcodes to the passed encoding" do
+      str = [0xA4, 0xA2].pack('CC').force_encoding Encoding::EUC_JP
+      str.send(@method, Encoding::UTF_8).should == "あ"
+    end
+
+    it "transcodes Japanese multibyte characters" do
+      str = "あいうえお"
+      str.send(@method, Encoding::ISO_2022_JP).should ==
+        "\e\x24\x42\x24\x22\x24\x24\x24\x26\x24\x28\x24\x2A\e\x28\x42".force_encoding(Encoding::ISO_2022_JP)
+    end
+
+    it "transcodes a 7-bit String despite no generic converting being available" do
+      lambda do
+        Encoding::Converter.new Encoding::Emacs_Mule, Encoding::ASCII_8BIT
+      end.should raise_error(Encoding::ConverterNotFoundError)
+
+      str = "\x79".force_encoding Encoding::ASCII_8BIT
+      str.send(@method, Encoding::Emacs_Mule).should == "y".force_encoding(Encoding::ASCII_8BIT)
+    end
+
+    it "raises an Encoding::ConverterNotFoundError when no conversion is possible" do
+      str = [0x80].pack('C').force_encoding Encoding::ASCII_8BIT
+      lambda do
+        str.send(@method, Encoding::Emacs_Mule)
+      end.should raise_error(Encoding::ConverterNotFoundError)
+    end
+
+    it "raises an Encoding::ConverterNotFoundError for an invalid encoding" do
+      lambda do
+        "abc".send(@method, "xyz")
+      end.should raise_error(Encoding::ConverterNotFoundError)
+    end
+  end
+
+  describe "when passed options" do
+    it "does not process transcoding options if not transcoding" do
+      result = "あ\ufffdあ".send(@method, undef: :replace)
+      result.should == "あ\ufffdあ"
+    end
+
+    it "calls #to_hash to convert the object" do
+      options = mock("string encode options")
+      options.should_receive(:to_hash).and_return({ undef: :replace })
+
+      result = "あ\ufffdあ".send(@method, options)
+      result.should == "あ\ufffdあ"
+    end
+
+    it "transcodes to Encoding.default_internal when set" do
+      Encoding.default_internal = Encoding::UTF_8
+      str = [0xA4, 0xA2].pack('CC').force_encoding Encoding::EUC_JP
+      str.send(@method, invalid: :replace).should == "あ"
+    end
+
+    it "raises an Encoding::ConverterNotFoundError when no conversion is possible despite 'invalid: :replace, undef: :replace'" do
+      Encoding.default_internal = Encoding::Emacs_Mule
+      str = [0x80].pack('C').force_encoding Encoding::ASCII_8BIT
+      lambda do
+        str.send(@method, invalid: :replace, undef: :replace)
+      end.should raise_error(Encoding::ConverterNotFoundError)
+    end
+
+    it "replaces invalid characters when replacing Emacs-Mule encoded strings" do
+      got = [0x80].pack('C').force_encoding('Emacs-Mule').send(@method, invalid: :replace)
+
+      got.should == "?".encode('Emacs-Mule')
+    end
+  end
+
+  describe "when passed to, from" do
+    it "transcodes between the encodings ignoring the String encoding" do
+      str = "あ"
+      result = [0xA6, 0xD0, 0x8F, 0xAB, 0xE4, 0x8F, 0xAB, 0xB1].pack('C8')
+      result.force_encoding Encoding::EUC_JP
+      str.send(@method, "euc-jp", "ibm437").should == result
+    end
+
+    it "calls #to_str to convert the from object to an Encoding" do
+      enc = mock("string encode encoding")
+      enc.should_receive(:to_str).and_return("ibm437")
+
+      str = "あ"
+      result = [0xA6, 0xD0, 0x8F, 0xAB, 0xE4, 0x8F, 0xAB, 0xB1].pack('C8')
+      result.force_encoding Encoding::EUC_JP
+
+      str.send(@method, "euc-jp", enc).should == result
+    end
+  end
+
+  describe "when passed to, options" do
+    it "replaces undefined characters in the destination encoding" do
+      result = "あ?あ".send(@method, Encoding::EUC_JP, undef: :replace)
+      # testing for: "\xA4\xA2?\xA4\xA2"
+      xA4xA2 = [0xA4, 0xA2].pack('CC')
+      result.should == "#{xA4xA2}?#{xA4xA2}".force_encoding("euc-jp")
+    end
+
+    it "replaces invalid characters in the destination encoding" do
+      xFF = [0xFF].pack('C').force_encoding('utf-8')
+      "ab#{xFF}c".send(@method, Encoding::ISO_8859_1, invalid: :replace).should == "ab?c"
+    end
+
+    it "calls #to_hash to convert the options object" do
+      options = mock("string encode options")
+      options.should_receive(:to_hash).and_return({ undef: :replace })
+
+      result = "あ?あ".send(@method, Encoding::EUC_JP, options)
+      xA4xA2 = [0xA4, 0xA2].pack('CC').force_encoding('utf-8')
+      result.should == "#{xA4xA2}?#{xA4xA2}".force_encoding("euc-jp")
+    end
+  end
+
+  describe "when passed to, from, options" do
+    it "replaces undefined characters in the destination encoding" do
+      str = "あ?あ".force_encoding Encoding::ASCII_8BIT
+      result = str.send(@method, "euc-jp", "utf-8", undef: :replace)
+      xA4xA2 = [0xA4, 0xA2].pack('CC').force_encoding('utf-8')
+      result.should == "#{xA4xA2}?#{xA4xA2}".force_encoding("euc-jp")
+    end
+
+    it "replaces invalid characters in the destination encoding" do
+      xFF = [0xFF].pack('C').force_encoding('utf-8')
+      str = "ab#{xFF}c".force_encoding Encoding::ASCII_8BIT
+      str.send(@method, "iso-8859-1", "utf-8", invalid: :replace).should == "ab?c"
+    end
+
+    it "calls #to_str to convert the to object to an encoding" do
+      to = mock("string encode to encoding")
+      to.should_receive(:to_str).and_return("iso-8859-1")
+
+      xFF = [0xFF].pack('C').force_encoding('utf-8')
+      str = "ab#{xFF}c".force_encoding Encoding::ASCII_8BIT
+      str.send(@method, to, "utf-8", invalid: :replace).should == "ab?c"
+    end
+
+    it "calls #to_str to convert the from object to an encoding" do
+      from = mock("string encode to encoding")
+      from.should_receive(:to_str).and_return("utf-8")
+
+      xFF = [0xFF].pack('C').force_encoding('utf-8')
+      str = "ab#{xFF}c".force_encoding Encoding::ASCII_8BIT
+      str.send(@method, "iso-8859-1", from, invalid: :replace).should == "ab?c"
+    end
+
+    it "calls #to_hash to convert the options object" do
+      options = mock("string encode options")
+      options.should_receive(:to_hash).and_return({ invalid: :replace })
+
+      xFF = [0xFF].pack('C').force_encoding('utf-8')
+      str = "ab#{xFF}c".force_encoding Encoding::ASCII_8BIT
+      str.send(@method, "iso-8859-1", "utf-8", options).should == "ab?c"
+    end
+  end
+
+  describe "given the xml: :text option" do
+    it "replaces all instances of '&' with '&'" do
+      '& and &'.send(@method, "UTF-8", xml: :text).should == '& and &'
+    end
+
+    it "replaces all instances of '<' with '&lt;'" do
+      '< and <'.send(@method, "UTF-8", xml: :text).should == '&lt; and &lt;'
+    end
+
+    it "replaces all instances of '>' with '&gt;'" do
+      '> and >'.send(@method, "UTF-8", xml: :text).should == '&gt; and &gt;'
+    end
+
+    it "does not replace '\"'" do
+      '" and "'.send(@method, "UTF-8", xml: :text).should == '" and "'
+    end
+
+    it "replaces undefined characters with their upper-case hexadecimal numeric character references" do
+      'ürst'.send(@method, Encoding::US_ASCII, xml: :text).should == '&#xFC;rst'
+    end
+  end
+
+  describe "given the xml: :attr option" do
+    it "surrounds the encoded text with double-quotes" do
+      'abc'.send(@method, "UTF-8", xml: :attr).should == '"abc"'
+    end
+
+    it "replaces all instances of '&' with '&amp;'" do
+      '& and &'.send(@method, "UTF-8", xml: :attr).should == '"&amp; and &amp;"'
+    end
+
+    it "replaces all instances of '<' with '&lt;'" do
+      '< and <'.send(@method, "UTF-8", xml: :attr).should == '"&lt; and &lt;"'
+    end
+
+    it "replaces all instances of '>' with '&gt;'" do
+      '> and >'.send(@method, "UTF-8", xml: :attr).should == '"&gt; and &gt;"'
+    end
+
+    it "replaces all instances of '\"' with '&quot;'" do
+      '" and "'.send(@method, "UTF-8", xml: :attr).should == '"&quot; and &quot;"'
+    end
+
+    it "replaces undefined characters with their upper-case hexadecimal numeric character references" do
+      'ürst'.send(@method, Encoding::US_ASCII, xml: :attr).should == '"&#xFC;rst"'
+    end
+  end
+
+  it "raises ArgumentError if the value of the :xml option is not :text or :attr" do
+    lambda { ''.send(@method, "UTF-8", xml: :other) }.should raise_error(ArgumentError)
+  end
+end

spec/ruby/core/string/shared/eql.rb

@@ -0,0 +1,34 @@
+# -*- encoding: binary -*-
+require File.expand_path('../../../../spec_helper', __FILE__)
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :string_eql_value, shared: true do
+  it "returns true if self <=> string returns 0" do
+    'hello'.send(@method, 'hello').should be_true
+  end
+
+  it "returns false if self <=> string does not return 0" do
+    "more".send(@method, "MORE").should be_false
+    "less".send(@method, "greater").should be_false
+  end
+
+  it "ignores encoding difference of compatible string" do
+    "hello".force_encoding("utf-8").send(@method, "hello".force_encoding("iso-8859-1")).should be_true
+  end
+
+  it "considers encoding difference of incompatible string" do
+    "\xff".force_encoding("utf-8").send(@method, "\xff".force_encoding("iso-8859-1")).should be_false
+  end
+
+  it "considers encoding compatibility" do
+    "hello".force_encoding("utf-8").send(@method, "hello".force_encoding("utf-32le")).should be_false
+  end
+
+  it "ignores subclass differences" do
+    a = "hello"
+    b = StringSpecs::MyString.new("hello")
+
+    a.send(@method, b).should be_true
+    b.send(@method, a).should be_true
+  end
+end

spec/ruby/core/string/shared/equal_value.rb

@@ -0,0 +1,29 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :string_equal_value, shared: true do
+  it "returns false if obj does not respond to to_str" do
+    'hello'.send(@method, 5).should be_false
+    not_supported_on :opal do
+      'hello'.send(@method, :hello).should be_false
+    end
+    'hello'.send(@method, mock('x')).should be_false
+  end
+
+  it "returns obj == self if obj responds to to_str" do
+    obj = Object.new
+
+    # String#== merely checks if #to_str is defined. It does
+    # not call it.
+    obj.stub!(:to_str)
+
+    # Don't use @method for :== in `obj.should_recerive(:==)`
+    obj.should_receive(:==).and_return(true)
+
+    'hello'.send(@method, obj).should be_true
+  end
+
+  it "is not fooled by NUL characters" do
+    "abc\0def".send(@method, "abc\0xyz").should be_false
+  end
+end

spec/ruby/core/string/shared/length.rb

@@ -0,0 +1,28 @@
+# encoding: utf-8
+
+describe :string_length, shared: true do
+  it "returns the length of self" do
+    "".send(@method).should == 0
+    "\x00".send(@method).should == 1
+    "one".send(@method).should == 3
+    "two".send(@method).should == 3
+    "three".send(@method).should == 5
+    "four".send(@method).should == 4
+  end
+
+  with_feature :encoding do
+    it "returns the length of a string in different encodings" do
+      utf8_str = 'こにちわ' * 100
+      utf8_str.size.should == 400
+      utf8_str.encode(Encoding::UTF_32BE).size.should == 400
+      utf8_str.encode(Encoding::SHIFT_JIS).size.should == 400
+    end
+
+    it "returns the length of the new self after encoding is changed" do
+      str = 'こにちわ'
+      str.send(@method)
+
+      str.force_encoding('ASCII-8BIT').send(@method).should == 12
+    end
+  end
+end

spec/ruby/core/string/shared/replace.rb

@@ -0,0 +1,75 @@
+describe :string_replace, shared: true do
+  it "returns self" do
+    a = "a"
+    a.send(@method, "b").should equal(a)
+  end
+
+  it "replaces the content of self with other" do
+    a = "some string"
+    a.send(@method, "another string")
+    a.should == "another string"
+  end
+
+  it "taints self if other is tainted" do
+    a = ""
+    b = "".taint
+    a.send(@method, b)
+    a.tainted?.should == true
+  end
+
+  it "does not untaint self if other is untainted" do
+    a = "".taint
+    b = ""
+    a.send(@method, b)
+    a.tainted?.should == true
+  end
+
+  it "untrusts self if other is untrusted" do
+    a = ""
+    b = "".untrust
+    a.send(@method, b)
+    a.untrusted?.should == true
+  end
+
+  it "does not trust self if other is trusted" do
+    a = "".untrust
+    b = ""
+    a.send(@method, b)
+    a.untrusted?.should == true
+  end
+
+  it "replaces the encoding of self with that of other" do
+    a = "".encode("UTF-16LE")
+    b = "".encode("UTF-8")
+    a.send(@method, b)
+    a.encoding.should == Encoding::UTF_8
+  end
+
+  it "carries over the encoding invalidity" do
+    a = "\u{8765}".force_encoding('ascii')
+    "".send(@method, a).valid_encoding?.should be_false
+  end
+
+  it "tries to convert other to string using to_str" do
+    other = mock('x')
+    other.should_receive(:to_str).and_return("converted to a string")
+    "hello".send(@method, other).should == "converted to a string"
+  end
+
+  it "raises a TypeError if other can't be converted to string" do
+    lambda { "hello".send(@method, 123)       }.should raise_error(TypeError)
+    lambda { "hello".send(@method, [])        }.should raise_error(TypeError)
+    lambda { "hello".send(@method, mock('x')) }.should raise_error(TypeError)
+  end
+
+  it "raises a RuntimeError on a frozen instance that is modified" do
+    a = "hello".freeze
+    lambda { a.send(@method, "world") }.should raise_error(RuntimeError)
+  end
+
+  # see [ruby-core:23666]
+  it "raises a RuntimeError on a frozen instance when self-replacing" do
+    a = "hello".freeze
+    lambda { a.send(@method, a) }.should raise_error(RuntimeError)
+  end
+end

spec/ruby/core/string/shared/slice.rb

@@ -0,0 +1,557 @@
+describe :string_slice, shared: true do
+  it "returns the character code of the character at the given index" do
+    "hello".send(@method, 0).should == ?h
+    "hello".send(@method, -1).should == ?o
+  end
+
+  it "returns nil if index is outside of self" do
+    "hello".send(@method, 20).should == nil
+    "hello".send(@method, -20).should == nil
+
+    "".send(@method, 0).should == nil
+    "".send(@method, -1).should == nil
+  end
+
+  it "calls to_int on the given index" do
+    "hello".send(@method, 0.5).should == ?h
+
+    obj = mock('1')
+    obj.should_receive(:to_int).and_return(1)
+    "hello".send(@method, obj).should == ?e
+  end
+
+  it "raises a TypeError if the given index is nil" do
+    lambda { "hello".send(@method, nil) }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError if the given index can't be converted to an Integer" do
+    lambda { "hello".send(@method, mock('x')) }.should raise_error(TypeError)
+    lambda { "hello".send(@method, {})        }.should raise_error(TypeError)
+    lambda { "hello".send(@method, [])        }.should raise_error(TypeError)
+  end
+
+  it "raises a RangeError if the index is too big" do
+    lambda { "hello".send(@method, bignum_value) }.should raise_error(RangeError)
+  end
+end
+
+describe :string_slice_index_length, shared: true do
+  it "returns the substring starting at the given index with the given length" do
+    "hello there".send(@method, 0,0).should == ""
+    "hello there".send(@method, 0,1).should == "h"
+    "hello there".send(@method, 0,3).should == "hel"
+    "hello there".send(@method, 0,6).should == "hello "
+    "hello there".send(@method, 0,9).should == "hello the"
+    "hello there".send(@method, 0,12).should == "hello there"
+
+    "hello there".send(@method, 1,0).should == ""
+    "hello there".send(@method, 1,1).should == "e"
+    "hello there".send(@method, 1,3).should == "ell"
+    "hello there".send(@method, 1,6).should == "ello t"
+    "hello there".send(@method, 1,9).should == "ello ther"
+    "hello there".send(@method, 1,12).should == "ello there"
+
+    "hello there".send(@method, 3,0).should == ""
+    "hello there".send(@method, 3,1).should == "l"
+    "hello there".send(@method, 3,3).should == "lo "
+    "hello there".send(@method, 3,6).should == "lo the"
+    "hello there".send(@method, 3,9).should == "lo there"
+
+    "hello there".send(@method, 4,0).should == ""
+    "hello there".send(@method, 4,3).should == "o t"
+    "hello there".send(@method, 4,6).should == "o ther"
+    "hello there".send(@method, 4,9).should == "o there"
+
+    "foo".send(@method, 2,1).should == "o"
+    "foo".send(@method, 3,0).should == ""
+    "foo".send(@method, 3,1).should == ""
+
+    "".send(@method, 0,0).should == ""
+    "".send(@method, 0,1).should == ""
+
+    "x".send(@method, 0,0).should == ""
+    "x".send(@method, 0,1).should == "x"
+    "x".send(@method, 1,0).should == ""
+    "x".send(@method, 1,1).should == ""
+
+    "x".send(@method, -1,0).should == ""
+    "x".send(@method, -1,1).should == "x"
+
+    "hello there".send(@method, -3,2).should == "er"
+  end
+
+  it "always taints resulting strings when self is tainted" do
+    str = "hello world"
+    str.taint
+
+    str.send(@method, 0,0).tainted?.should == true
+    str.send(@method, 0,1).tainted?.should == true
+    str.send(@method, 2,1).tainted?.should == true
+  end
+
+  it "returns a string with the same encoding" do
+    s = "hello there"
+    s.send(@method, 1, 9).encoding.should == s.encoding
+
+    a = "hello".force_encoding("binary")
+    b = " there".force_encoding("ISO-8859-1")
+    c = (a + b).force_encoding(Encoding::US_ASCII)
+
+    c.send(@method, 0, 5).encoding.should == Encoding::US_ASCII
+    c.send(@method, 5, 6).encoding.should == Encoding::US_ASCII
+    c.send(@method, 1, 3).encoding.should == Encoding::US_ASCII
+    c.send(@method, 8, 2).encoding.should == Encoding::US_ASCII
+    c.send(@method, 1, 10).encoding.should == Encoding::US_ASCII
+  end
+
+  it "returns nil if the offset falls outside of self" do
+    "hello there".send(@method, 20,3).should == nil
+    "hello there".send(@method, -20,3).should == nil
+
+    "".send(@method, 1,0).should == nil
+    "".send(@method, 1,1).should == nil
+
+    "".send(@method, -1,0).should == nil
+    "".send(@method, -1,1).should == nil
+
+    "x".send(@method, 2,0).should == nil
+    "x".send(@method, 2,1).should == nil
+
+    "x".send(@method, -2,0).should == nil
+    "x".send(@method, -2,1).should == nil
+  end
+
+  it "returns nil if the length is negative" do
+    "hello there".send(@method, 4,-3).should == nil
+    "hello there".send(@method, -4,-3).should == nil
+  end
+
+  it "calls to_int on the given index and the given length" do
+    "hello".send(@method, 0.5, 1).should == "h"
+    "hello".send(@method, 0.5, 2.5).should == "he"
+    "hello".send(@method, 1, 2.5).should == "el"
+
+    obj = mock('2')
+    obj.should_receive(:to_int).exactly(4).times.and_return(2)
+
+    "hello".send(@method, obj, 1).should == "l"
+    "hello".send(@method, obj, obj).should == "ll"
+    "hello".send(@method, 0, obj).should == "he"
+  end
+
+  it "raises a TypeError when idx or length can't be converted to an integer" do
+    lambda { "hello".send(@method, mock('x'), 0) }.should raise_error(TypeError)
+    lambda { "hello".send(@method, 0, mock('x')) }.should raise_error(TypeError)
+
+    # I'm deliberately including this here.
+    # It means that str.send(@method, other, idx) isn't supported.
+    lambda { "hello".send(@method, "", 0) }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError when the given index or the given length is nil" do
+    lambda { "hello".send(@method, 1, nil)   }.should raise_error(TypeError)
+    lambda { "hello".send(@method, nil, 1)   }.should raise_error(TypeError)
+    lambda { "hello".send(@method, nil, nil) }.should raise_error(TypeError)
+  end
+
+  it "raises a RangeError if the index or length is too big" do
+    lambda { "hello".send(@method, bignum_value, 1) }.should raise_error(RangeError)
+    lambda { "hello".send(@method, 0, bignum_value) }.should raise_error(RangeError)
+  end
+
+  it "returns subclass instances" do
+    s = StringSpecs::MyString.new("hello")
+    s.send(@method, 0,0).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, 0,4).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, 1,4).should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "handles repeated application" do
+    "hello world".send(@method, 6, 5).send(@method, 0, 1).should == 'w'
+    "hello world".send(@method, 6, 5).send(@method, 0, 5).should == 'world'
+
+    "hello world".send(@method, 6, 5).send(@method, 1, 1).should == 'o'
+    "hello world".send(@method, 6, 5).send(@method, 1, 4).should == 'orld'
+
+    "hello world".send(@method, 6, 5).send(@method, 4, 1).should == 'd'
+    "hello world".send(@method, 6, 5).send(@method, 5, 0).should == ''
+
+    "hello world".send(@method, 6, 0).send(@method, -1, 0).should == nil
+    "hello world".send(@method, 6, 0).send(@method, 1, 1).should == nil
+  end
+end
+
+describe :string_slice_range, shared: true do
+  it "returns the substring given by the offsets of the range" do
+    "hello there".send(@method, 1..1).should == "e"
+    "hello there".send(@method, 1..3).should == "ell"
+    "hello there".send(@method, 1...3).should == "el"
+    "hello there".send(@method, -4..-2).should == "her"
+    "hello there".send(@method, -4...-2).should == "he"
+    "hello there".send(@method, 5..-1).should == " there"
+    "hello there".send(@method, 5...-1).should == " ther"
+
+    "".send(@method, 0..0).should == ""
+
+    "x".send(@method, 0..0).should == "x"
+    "x".send(@method, 0..1).should == "x"
+    "x".send(@method, 0...1).should == "x"
+    "x".send(@method, 0..-1).should == "x"
+
+    "x".send(@method, 1..1).should == ""
+    "x".send(@method, 1..-1).should == ""
+  end
+
+  it "returns nil if the beginning of the range falls outside of self" do
+    "hello there".send(@method, 12..-1).should == nil
+    "hello there".send(@method, 20..25).should == nil
+    "hello there".send(@method, 20..1).should == nil
+    "hello there".send(@method, -20..1).should == nil
+    "hello there".send(@method, -20..-1).should == nil
+
+    "".send(@method, -1..-1).should == nil
+    "".send(@method, -1...-1).should == nil
+    "".send(@method, -1..0).should == nil
+    "".send(@method, -1...0).should == nil
+  end
+
+  it "returns an empty string if range.begin is inside self and > real end" do
+    "hello there".send(@method, 1...1).should == ""
+    "hello there".send(@method, 4..2).should == ""
+    "hello".send(@method, 4..-4).should == ""
+    "hello there".send(@method, -5..-6).should == ""
+    "hello there".send(@method, -2..-4).should == ""
+    "hello there".send(@method, -5..-6).should == ""
+    "hello there".send(@method, -5..2).should == ""
+
+    "".send(@method, 0...0).should == ""
+    "".send(@method, 0..-1).should == ""
+    "".send(@method, 0...-1).should == ""
+
+    "x".send(@method, 0...0).should == ""
+    "x".send(@method, 0...-1).should == ""
+    "x".send(@method, 1...1).should == ""
+    "x".send(@method, 1...-1).should == ""
+  end
+
+  it "always taints resulting strings when self is tainted" do
+    str = "hello world"
+    str.taint
+
+    str.send(@method, 0..0).tainted?.should == true
+    str.send(@method, 0...0).tainted?.should == true
+    str.send(@method, 0..1).tainted?.should == true
+    str.send(@method, 0...1).tainted?.should == true
+    str.send(@method, 2..3).tainted?.should == true
+    str.send(@method, 2..0).tainted?.should == true
+  end
+
+  it "returns subclass instances" do
+    s = StringSpecs::MyString.new("hello")
+    s.send(@method, 0...0).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, 0..4).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, 1..4).should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "calls to_int on range arguments" do
+    from = mock('from')
+    to = mock('to')
+
+    # So we can construct a range out of them...
+    from.should_receive(:<=>).twice.and_return(0)
+
+    from.should_receive(:to_int).twice.and_return(1)
+    to.should_receive(:to_int).twice.and_return(-2)
+
+    "hello there".send(@method, from..to).should == "ello ther"
+    "hello there".send(@method, from...to).should == "ello the"
+  end
+
+  it "works with Range subclasses" do
+    a = "GOOD"
+    range_incl = StringSpecs::MyRange.new(1, 2)
+    range_excl = StringSpecs::MyRange.new(-3, -1, true)
+
+    a.send(@method, range_incl).should == "OO"
+    a.send(@method, range_excl).should == "OO"
+  end
+
+  it "handles repeated application" do
+    "hello world".send(@method, 6..11).send(@method, 0..0).should == 'w'
+    "hello world".send(@method, 6..11).send(@method, 0..4).should == 'world'
+
+    "hello world".send(@method, 6..11).send(@method, 1..1).should == 'o'
+    "hello world".send(@method, 6..11).send(@method, 1..4).should == 'orld'
+
+    "hello world".send(@method, 6..11).send(@method, 4..4).should == 'd'
+    "hello world".send(@method, 6..11).send(@method, 5..4).should == ''
+
+    "hello world".send(@method, 6..5).send(@method, -1..-1).should == nil
+    "hello world".send(@method, 6..5).send(@method, 1..1).should == nil
+  end
+end
+
+describe :string_slice_regexp, shared: true do
+  it "returns the matching portion of self" do
+    "hello there".send(@method, /[aeiou](.)\1/).should == "ell"
+    "".send(@method, //).should == ""
+  end
+
+  it "returns nil if there is no match" do
+    "hello there".send(@method, /xyz/).should == nil
+  end
+
+  not_supported_on :opal do
+    it "always taints resulting strings when self or regexp is tainted" do
+      strs = ["hello world"]
+      strs += strs.map { |s| s.dup.taint }
+
+      strs.each do |str|
+        str.send(@method, //).tainted?.should == str.tainted?
+        str.send(@method, /hello/).tainted?.should == str.tainted?
+
+        tainted_re = /./
+        tainted_re.taint
+
+        str.send(@method, tainted_re).tainted?.should == true
+      end
+    end
+
+    it "returns an untrusted string if the regexp is untrusted" do
+      "hello".send(@method, /./.untrust).untrusted?.should be_true
+    end
+  end
+
+  it "returns subclass instances" do
+    s = StringSpecs::MyString.new("hello")
+    s.send(@method, //).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, /../).should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "sets $~ to MatchData when there is a match and nil when there's none" do
+    'hello'.send(@method, /./)
+    $~[0].should == 'h'
+
+    'hello'.send(@method, /not/)
+    $~.should == nil
+  end
+end
+
+describe :string_slice_regexp_index, shared: true do
+  it "returns the capture for the given index" do
+    "hello there".send(@method, /[aeiou](.)\1/, 0).should == "ell"
+    "hello there".send(@method, /[aeiou](.)\1/, 1).should == "l"
+    "hello there".send(@method, /[aeiou](.)\1/, -1).should == "l"
+
+    "har".send(@method, /(.)(.)(.)/, 0).should == "har"
+    "har".send(@method, /(.)(.)(.)/, 1).should == "h"
+    "har".send(@method, /(.)(.)(.)/, 2).should == "a"
+    "har".send(@method, /(.)(.)(.)/, 3).should == "r"
+    "har".send(@method, /(.)(.)(.)/, -1).should == "r"
+    "har".send(@method, /(.)(.)(.)/, -2).should == "a"
+    "har".send(@method, /(.)(.)(.)/, -3).should == "h"
+  end
+
+  it "always taints resulting strings when self or regexp is tainted" do
+    strs = ["hello world"]
+    strs += strs.map { |s| s.dup.taint }
+
+    strs.each do |str|
+      str.send(@method, //, 0).tainted?.should == str.tainted?
+      str.send(@method, /hello/, 0).tainted?.should == str.tainted?
+
+      str.send(@method, /(.)(.)(.)/, 0).tainted?.should == str.tainted?
+      str.send(@method, /(.)(.)(.)/, 1).tainted?.should == str.tainted?
+      str.send(@method, /(.)(.)(.)/, -1).tainted?.should == str.tainted?
+      str.send(@method, /(.)(.)(.)/, -2).tainted?.should == str.tainted?
+
+      tainted_re = /(.)(.)(.)/
+      tainted_re.taint
+
+      str.send(@method, tainted_re, 0).tainted?.should == true
+      str.send(@method, tainted_re, 1).tainted?.should == true
+      str.send(@method, tainted_re, -1).tainted?.should == true
+    end
+  end
+
+  not_supported_on :opal do
+    it "returns an untrusted string if the regexp is untrusted" do
+      "hello".send(@method, /(.)/.untrust, 1).untrusted?.should be_true
+    end
+  end
+
+  it "returns nil if there is no match" do
+    "hello there".send(@method, /(what?)/, 1).should == nil
+  end
+
+  it "returns nil if there is no capture for the given index" do
+    "hello there".send(@method, /[aeiou](.)\1/, 2).should == nil
+    # You can't refer to 0 using negative indices
+    "hello there".send(@method, /[aeiou](.)\1/, -2).should == nil
+  end
+
+  it "calls to_int on the given index" do
+    obj = mock('2')
+    obj.should_receive(:to_int).and_return(2)
+
+    "har".send(@method, /(.)(.)(.)/, 1.5).should == "h"
+    "har".send(@method, /(.)(.)(.)/, obj).should == "a"
+  end
+
+  it "raises a TypeError when the given index can't be converted to Integer" do
+    lambda { "hello".send(@method, /(.)(.)(.)/, mock('x')) }.should raise_error(TypeError)
+    lambda { "hello".send(@method, /(.)(.)(.)/, {})        }.should raise_error(TypeError)
+    lambda { "hello".send(@method, /(.)(.)(.)/, [])        }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError when the given index is nil" do
+    lambda { "hello".send(@method, /(.)(.)(.)/, nil) }.should raise_error(TypeError)
+  end
+
+  it "returns subclass instances" do
+    s = StringSpecs::MyString.new("hello")
+    s.send(@method, /(.)(.)/, 0).should be_an_instance_of(StringSpecs::MyString)
+    s.send(@method, /(.)(.)/, 1).should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "sets $~ to MatchData when there is a match and nil when there's none" do
+    'hello'.send(@method, /.(.)/, 0)
+    $~[0].should == 'he'
+
+    'hello'.send(@method, /.(.)/, 1)
+    $~[1].should == 'e'
+
+    'hello'.send(@method, /not/, 0)
+    $~.should == nil
+  end
+end
+
+describe :string_slice_string, shared: true do
+  it "returns other_str if it occurs in self" do
+    s = "lo"
+    "hello there".send(@method, s).should == s
+  end
+
+  it "taints resulting strings when other is tainted" do
+    strs = ["", "hello world", "hello"]
+    strs += strs.map { |s| s.dup.taint }
+
+    strs.each do |str|
+      strs.each do |other|
+        r = str.send(@method, other)
+
+        r.tainted?.should == !r.nil? & other.tainted?
+      end
+    end
+  end
+
+  it "doesn't set $~" do
+    $~ = nil
+
+    'hello'.send(@method, 'll')
+    $~.should == nil
+  end
+
+  it "returns nil if there is no match" do
+    "hello there".send(@method, "bye").should == nil
+  end
+
+  it "doesn't call to_str on its argument" do
+    o = mock('x')
+    o.should_not_receive(:to_str)
+
+    lambda { "hello".send(@method, o) }.should raise_error(TypeError)
+  end
+
+  it "returns a subclass instance when given a subclass instance" do
+    s = StringSpecs::MyString.new("el")
+    r = "hello".send(@method, s)
+    r.should == "el"
+    r.should be_an_instance_of(StringSpecs::MyString)
+  end
+end
+
+describe :string_slice_regexp_group, shared: true do
+  not_supported_on :opal do
+    it "returns the capture for the given name" do
+      "hello there".send(@method, /(?<g>[aeiou](.))/, 'g').should == "el"
+      "hello there".send(@method, /[aeiou](?<g>.)/, 'g').should == "l"
+
+      "har".send(@method, /(?<g>(.)(.)(.))/, 'g').should == "har"
+      "har".send(@method, /(?<h>.)(.)(.)/, 'h').should == "h"
+      "har".send(@method, /(.)(?<a>.)(.)/, 'a').should == "a"
+      "har".send(@method, /(.)(.)(?<r>.)/, 'r').should == "r"
+      "har".send(@method, /(?<h>.)(?<a>.)(?<r>.)/, 'r').should == "r"
+    end
+
+    it "returns the last capture for duplicate names" do
+      "hello there".send(@method, /(?<g>h)(?<g>.)/, 'g').should == "e"
+      "hello there".send(@method, /(?<g>h)(?<g>.)(?<f>.)/, 'g').should == "e"
+    end
+
+    it "returns the innermost capture for nested duplicate names" do
+      "hello there".send(@method, /(?<g>h(?<g>.))/, 'g').should == "e"
+    end
+
+    it "always taints resulting strings when self or regexp is tainted" do
+      strs = ["hello world"]
+      strs += strs.map { |s| s.dup.taint }
+
+      strs.each do |str|
+        str.send(@method, /(?<hi>hello)/, 'hi').tainted?.should == str.tainted?
+
+        str.send(@method, /(?<g>(.)(.)(.))/, 'g').tainted?.should == str.tainted?
+        str.send(@method, /(?<h>.)(.)(.)/, 'h').tainted?.should == str.tainted?
+        str.send(@method, /(.)(?<a>.)(.)/, 'a').tainted?.should == str.tainted?
+        str.send(@method, /(.)(.)(?<r>.)/, 'r').tainted?.should == str.tainted?
+        str.send(@method, /(?<h>.)(?<a>.)(?<r>.)/, 'r').tainted?.should == str.tainted?
+
+        tainted_re = /(?<a>.)(?<b>.)(?<c>.)/
+        tainted_re.taint
+
+        str.send(@method, tainted_re, 'a').tainted?.should be_true
+        str.send(@method, tainted_re, 'b').tainted?.should be_true
+        str.send(@method, tainted_re, 'c').tainted?.should be_true
+      end
+    end
+
+    it "returns nil if there is no match" do
+      "hello there".send(@method, /(?<whut>what?)/, 'whut').should be_nil
+    end
+
+    it "raises an IndexError if there is no capture for the given name" do
+      lambda do
+        "hello there".send(@method, /[aeiou](.)\1/, 'non')
+      end.should raise_error(IndexError)
+    end
+
+    it "raises a TypeError when the given name is not a String" do
+      lambda { "hello".send(@method, /(?<q>.)/, mock('x')) }.should raise_error(TypeError)
+      lambda { "hello".send(@method, /(?<q>.)/, {})        }.should raise_error(TypeError)
+      lambda { "hello".send(@method, /(?<q>.)/, [])        }.should raise_error(TypeError)
+    end
+
+    it "raises an IndexError when given the empty String as a group name" do
+      lambda { "hello".send(@method, /(?<q>)/, '') }.should raise_error(IndexError)
+    end
+
+    it "returns subclass instances" do
+      s = StringSpecs::MyString.new("hello")
+      s.send(@method, /(?<q>.)/, 'q').should be_an_instance_of(StringSpecs::MyString)
+    end
+
+    it "sets $~ to MatchData when there is a match and nil when there's none" do
+      'hello'.send(@method, /(?<hi>.(.))/, 'hi')
+      $~[0].should == 'he'
+
+      'hello'.send(@method, /(?<non>not)/, 'non')
+      $~.should be_nil
+    end
+  end
+end
+
+describe :string_slice_symbol, shared: true do
+  it "raises TypeError" do
+    lambda { 'hello'.send(@method, :hello) }.should raise_error(TypeError)
+  end
+end

spec/ruby/core/string/shared/succ.rb

@@ -0,0 +1,88 @@
+# -*- encoding: binary -*-
+describe :string_succ, shared: true do
+  it "returns an empty string for empty strings" do
+    "".send(@method).should == ""
+  end
+
+  it "returns the successor by increasing the rightmost alphanumeric (digit => digit, letter => letter with same case)" do
+    "abcd".send(@method).should == "abce"
+    "THX1138".send(@method).should == "THX1139"
+
+    "<<koala>>".send(@method).should == "<<koalb>>"
+    "==A??".send(@method).should == "==B??"
+  end
+
+  it "increases non-alphanumerics (via ascii rules) if there are no alphanumerics" do
+    "***".send(@method).should == "**+"
+    "**`".send(@method).should == "**a"
+  end
+
+  it "increases the next best alphanumeric (jumping over non-alphanumerics) if there is a carry" do
+    "dz".send(@method).should == "ea"
+    "HZ".send(@method).should == "IA"
+    "49".send(@method).should == "50"
+
+    "izz".send(@method).should == "jaa"
+    "IZZ".send(@method).should == "JAA"
+    "699".send(@method).should == "700"
+
+    "6Z99z99Z".send(@method).should == "7A00a00A"
+
+    "1999zzz".send(@method).should == "2000aaa"
+    "NZ/[]ZZZ9999".send(@method).should == "OA/[]AAA0000"
+  end
+
+  it "increases the next best character if there is a carry for non-alphanumerics" do
+    "(\xFF".send(@method).should == ")\x00"
+    "`\xFF".send(@method).should == "a\x00"
+    "<\xFF\xFF".send(@method).should == "=\x00\x00"
+  end
+
+  it "adds an additional character (just left to the last increased one) if there is a carry and no character left to increase" do
+    "z".send(@method).should == "aa"
+    "Z".send(@method).should == "AA"
+    "9".send(@method).should == "10"
+
+    "zz".send(@method).should == "aaa"
+    "ZZ".send(@method).should == "AAA"
+    "99".send(@method).should == "100"
+
+    "9Z99z99Z".send(@method).should == "10A00a00A"
+
+    "ZZZ9999".send(@method).should == "AAAA0000"
+    "/[]9999".send(@method).should == "/[]10000"
+    "/[]ZZZ9999".send(@method).should == "/[]AAAA0000"
+    "Z/[]ZZZ9999".send(@method).should == "AA/[]AAA0000"
+
+    # non-alphanumeric cases
+    "\xFF".send(@method).should == "\x01\x00"
+    "\xFF\xFF".send(@method).should == "\x01\x00\x00"
+  end
+
+  it "returns subclass instances when called on a subclass" do
+    StringSpecs::MyString.new("").send(@method).should be_an_instance_of(StringSpecs::MyString)
+    StringSpecs::MyString.new("a").send(@method).should be_an_instance_of(StringSpecs::MyString)
+    StringSpecs::MyString.new("z").send(@method).should be_an_instance_of(StringSpecs::MyString)
+  end
+
+  it "taints the result if self is tainted" do
+    ["", "a", "z", "Z", "9", "\xFF", "\xFF\xFF"].each do |s|
+      s.taint.send(@method).tainted?.should == true
+    end
+  end
+end
+
+describe :string_succ_bang, shared: true do
+  it "is equivalent to succ, but modifies self in place (still returns self)" do
+    ["", "abcd", "THX1138"].each do |s|
+      r = s.dup.send(@method)
+      s.send(@method).should equal(s)
+      s.should == r
+    end
+  end
+
+  it "raises a RuntimeError if self is frozen" do
+    lambda { "".freeze.send(@method)     }.should raise_error(RuntimeError)
+    lambda { "abcd".freeze.send(@method) }.should raise_error(RuntimeError)
+  end
+end

spec/ruby/core/string/shared/to_a.rb

@@ -0,0 +1,9 @@
+describe :string_to_a, shared: true do
+  it "returns an empty array for empty strings" do
+    "".send(@method).should == []
+  end
+
+  it "returns an array containing the string for non-empty strings" do
+    "hello".send(@method).should == ["hello"]
+  end
+end

spec/ruby/core/string/shared/to_s.rb

@@ -0,0 +1,18 @@
+describe :string_to_s, shared: true do
+  it "returns self when self.class == String" do
+    a = "a string"
+    a.should equal(a.send(@method))
+  end
+
+  it "returns a new instance of String when called on a subclass" do
+    a = StringSpecs::MyString.new("a string")
+    s = a.send(@method)
+    s.should == "a string"
+    s.should be_an_instance_of(String)
+  end
+
+  it "taints the result when self is tainted" do
+    "x".taint.send(@method).tainted?.should == true
+    StringSpecs::MyString.new("x").taint.send(@method).tainted?.should == true
+  end
+end

spec/ruby/core/string/shared/to_sym.rb

@@ -0,0 +1,24 @@
+describe :string_to_sym, shared: true do
+  it "returns the symbol corresponding to self" do
+    "Koala".send(@method).should == :Koala
+    'cat'.send(@method).should == :cat
+    '@cat'.send(@method).should == :@cat
+    'cat and dog'.send(@method).should == :"cat and dog"
+    "abc=".send(@method).should == :abc=
+  end
+
+  it "does not special case +(binary) and -(binary)" do
+    "+(binary)".send(@method).should == :"+(binary)"
+    "-(binary)".send(@method).should == :"-(binary)"
+  end
+
+  it "does not special case certain operators" do
+    [ ["!@", :"!@"],
+      ["~@", :"~@"],
+      ["!(unary)", :"!(unary)"],
+      ["~(unary)", :"~(unary)"],
+      ["+(unary)", :"+(unary)"],
+      ["-(unary)", :"-(unary)"]
+    ].should be_computed_by(@method)
+  end
+end