1 files changed, 162 insertions, 0 deletions
diff --git a/spec/ruby/core/string/shared/each_line.rb b/spec/ruby/core/string/shared/each_line.rb
new file mode 100644
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+++ b/spec/ruby/core/string/shared/each_line.rb
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+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 "splits strings containing multibyte characters" do
+    s = <<~EOS
+      foo
+      🤡🤡🤡🤡🤡🤡🤡
+      bar
+      baz
+    EOS
+
+    b = []
+    s.send(@method) { |part| b << part }
+    b.should == ["foo\n", "🤡🤡🤡🤡🤡🤡🤡\n", "bar\n", "baz\n"]
+  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
+
+  it "yields paragraphs (broken by 2 or more successive newlines) when passed '' and replaces multiple newlines with only two ones" do
+    a = []
+    "hello\nworld\n\n\nand\nuniverse\n\n\n\n\n".send(@method, '') { |s| a << s }
+    a.should == ["hello\nworld\n\n", "and\nuniverse\n\n"]
+
+    a = []
+    "hello\nworld\n\n\nand\nuniverse\n\n\n\n\ndog".send(@method, '') { |s| a << s }
+    a.should == ["hello\nworld\n\n", "and\nuniverse\n\n", "dog"]
+  end
+
+  describe "uses $/" do
+    before :each do
+      @before_separator = $/
+    end
+
+    after :each do
+      suppress_warning {$/ = @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 }
+
+          suppress_warning {$/ = sep}
+
+          actual = []
+          suppress_warning {str.send(@method) { |x| actual << x }}
+
+          actual.should == expected
+        end
+      end
+    end
+  end
+
+  it "yields String instances for subclasses" do
+    a = []
+    StringSpecs::MyString.new("hello\nworld").send(@method) { |s| a << s.class }
+    a.should == [String, String]
+  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 "returns Strings in the same encoding as self" do
+    "one\ntwo\r\nthree".encode("US-ASCII").send(@method) do |s|
+      s.encoding.should == Encoding::US_ASCII
+    end
+  end
+
+  it "raises a TypeError when the separator can't be converted to a string" do
+    -> { "hello world".send(@method, false) {}     }.should raise_error(TypeError)
+    -> { "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
+    -> { "hello world".send(@method, :o).to_a }.should raise_error(TypeError)
+  end
+
+  context "when `chomp` keyword argument is passed" do
+    it "removes new line characters when separator is not specified" do
+      a = []
+      "hello \nworld\n".send(@method, chomp: true) { |s| a << s }
+      a.should == ["hello ", "world"]
+
+      a = []
+      "hello \r\nworld\r\n".send(@method, chomp: true) { |s| a << s }
+      a.should == ["hello ", "world"]
+    end
+
+    it "removes only specified separator" do
+      a = []
+      "hello world".send(@method, ' ', chomp: true) { |s| a << s }
+      a.should == ["hello", "world"]
+    end
+
+    # https://bugs.ruby-lang.org/issues/14257
+    it "ignores new line characters when separator is specified" do
+      a = []
+      "hello\n world\n".send(@method, ' ', chomp: true) { |s| a << s }
+      a.should == ["hello\n", "world\n"]
+
+      a = []
+      "hello\r\n world\r\n".send(@method, ' ', chomp: true) { |s| a << s }
+      a.should == ["hello\r\n", "world\r\n"]
+    end
+  end
+end