Update to ruby/spec@37e52e5

3 files changed, 151 insertions, 0 deletions

diff --git a/spec/ruby/language/regexp/back-references_spec.rb b/spec/ruby/language/regexp/back-references_spec.rb
index e8df8725c5..26750c20c5 100644
--- a/spec/ruby/language/regexp/back-references_spec.rb
+++ b/spec/ruby/language/regexp/back-references_spec.rb
@@ -63,6 +63,11 @@ describe "Regexps with back-references" do
     (/\10()()()()()()()()()()/ =~ "\x08").should == 0
   end
 
+  it "fails when trying to match a backreference to an unmatched capture group" do
+    /\1()/.match("").should == nil
+    /(?:(a)|b)\1/.match("b").should == nil
+  end
+
   it "ignores backreferences > 1000" do
     /\99999/.match("99999")[0].should == "99999"
   end
diff --git a/spec/ruby/language/regexp/empty_checks_spec.rb b/spec/ruby/language/regexp/empty_checks_spec.rb
new file mode 100644
index 0000000000..391e65b003
--- /dev/null
+++ b/spec/ruby/language/regexp/empty_checks_spec.rb
@@ -0,0 +1,135 @@
+require_relative '../../spec_helper'
+require_relative '../fixtures/classes'
+
+describe "empty checks in Regexps" do
+
+  it "allow extra empty iterations" do
+    /()?/.match("").to_a.should == ["", ""]
+    /(a*)?/.match("").to_a.should == ["", ""]
+    /(a*)*/.match("").to_a.should == ["", ""]
+    # The bounds are high to avoid DFA-based matchers in implementations
+    # and to check backtracking behavior.
+    /(?:a|()){500,1000}/.match("a" * 500).to_a.should == ["a" * 500, ""]
+
+    # Variations with non-greedy loops.
+    /()??/.match("").to_a.should == ["", nil]
+    /(a*?)?/.match("").to_a.should == ["", ""]
+    /(a*)??/.match("").to_a.should == ["", nil]
+    /(a*?)??/.match("").to_a.should == ["", nil]
+    /(a*?)*/.match("").to_a.should == ["", ""]
+    /(a*)*?/.match("").to_a.should == ["", nil]
+    /(a*?)*?/.match("").to_a.should == ["", nil]
+  end
+
+  it "allow empty iterations in the middle of a loop" do
+    # One empty iteration between a's and b's.
+    /(a|\2b|())*/.match("aaabbb").to_a.should == ["aaabbb", "", ""]
+    /(a|\2b|()){2,4}/.match("aaabbb").to_a.should == ["aaa", "", ""]
+
+    # Two empty iterations between a's and b's.
+    /(a|\2b|\3()|())*/.match("aaabbb").to_a.should == ["aaabbb", "", "", ""]
+    /(a|\2b|\3()|()){2,4}/.match("aaabbb").to_a.should == ["aaa", "", nil, ""]
+
+    # Check that the empty iteration correctly updates the loop counter.
+    /(a|\2b|()){20,24}/.match("a" * 20 + "b" * 5).to_a.should == ["a" * 20 + "b" * 3, "b", ""]
+
+    # Variations with non-greedy loops.
+    /(a|\2b|())*?/.match("aaabbb").to_a.should == ["", nil, nil]
+    /(a|\2b|()){2,4}/.match("aaabbb").to_a.should == ["aaa", "", ""]
+    /(a|\2b|\3()|())*?/.match("aaabbb").to_a.should == ["", nil, nil, nil]
+    /(a|\2b|\3()|()){2,4}/.match("aaabbb").to_a.should == ["aaa", "", nil, ""]
+    /(a|\2b|()){20,24}/.match("a" * 20 + "b" * 5).to_a.should == ["a" * 20 + "b" * 3, "b", ""]
+  end
+
+  it "make the Regexp proceed past the quantified expression on failure" do
+    # If the contents of the ()* quantified group are empty (i.e., they fail
+    # the empty check), the loop will abort. It will not try to backtrack
+    # and try other alternatives (e.g. matching the "a") like in other Regexp
+    # dialects such as ECMAScript.
+    /(?:|a)*/.match("aaa").to_a.should == [""]
+    /(?:()|a)*/.match("aaa").to_a.should == ["", ""]
+    /(|a)*/.match("aaa").to_a.should == ["", ""]
+    /(()|a)*/.match("aaa").to_a.should == ["", "", ""]
+
+    # Same expressions, but with backreferences, to force the use of non-DFA-based
+    # engines.
+    /()\1(?:|a)*/.match("aaa").to_a.should == ["", ""]
+    /()\1(?:()|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()\1(|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()\1(()|a)*/.match("aaa").to_a.should == ["", "", "", ""]
+
+    # Variations with other zero-width contents of the quantified
+    # group: backreferences, capture groups, lookarounds
+    /()(?:\1|a)*/.match("aaa").to_a.should == ["", ""]
+    /()(?:()\1|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()(?:(\1)|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()(?:\1()|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()(\1|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()(()\1|a)*/.match("aaa").to_a.should == ["", "", "", ""]
+    /()((\1)|a)*/.match("aaa").to_a.should == ["", "", "", ""]
+    /()(\1()|a)*/.match("aaa").to_a.should == ["", "", "", ""]
+
+    /(?:(?=a)|a)*/.match("aaa").to_a.should == [""]
+    /(?:(?=a)()|a)*/.match("aaa").to_a.should == ["", ""]
+    /(?:()(?=a)|a)*/.match("aaa").to_a.should == ["", ""]
+    /(?:((?=a))|a)*/.match("aaa").to_a.should == ["", ""]
+    /()\1(?:(?=a)|a)*/.match("aaa").to_a.should == ["", ""]
+    /()\1(?:(?=a)()|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()\1(?:()(?=a)|a)*/.match("aaa").to_a.should == ["", "", ""]
+    /()\1(?:((?=a))|a)*/.match("aaa").to_a.should == ["", "", ""]
+
+    # Variations with non-greedy loops.
+    /(?:|a)*?/.match("aaa").to_a.should == [""]
+    /(?:()|a)*?/.match("aaa").to_a.should == ["", nil]
+    /(|a)*?/.match("aaa").to_a.should == ["", nil]
+    /(()|a)*?/.match("aaa").to_a.should == ["", nil, nil]
+
+    /()\1(?:|a)*?/.match("aaa").to_a.should == ["", ""]
+    /()\1(?:()|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()\1(|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()\1(()|a)*?/.match("aaa").to_a.should == ["", "", nil, nil]
+
+    /()(?:\1|a)*?/.match("aaa").to_a.should == ["", ""]
+    /()(?:()\1|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()(?:(\1)|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()(?:\1()|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()(\1|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()(()\1|a)*?/.match("aaa").to_a.should == ["", "", nil, nil]
+    /()((\1)|a)*?/.match("aaa").to_a.should == ["", "", nil, nil]
+    /()(\1()|a)*?/.match("aaa").to_a.should == ["", "", nil, nil]
+
+    /(?:(?=a)|a)*?/.match("aaa").to_a.should == [""]
+    /(?:(?=a)()|a)*?/.match("aaa").to_a.should == ["", nil]
+    /(?:()(?=a)|a)*?/.match("aaa").to_a.should == ["", nil]
+    /(?:((?=a))|a)*?/.match("aaa").to_a.should == ["", nil]
+    /()\1(?:(?=a)|a)*?/.match("aaa").to_a.should == ["", ""]
+    /()\1(?:(?=a)()|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()\1(?:()(?=a)|a)*?/.match("aaa").to_a.should == ["", "", nil]
+    /()\1(?:((?=a))|a)*?/.match("aaa").to_a.should == ["", "", nil]
+  end
+
+  it "shouldn't cause the Regexp parser to get stuck in a loop" do
+    /(|a|\2b|())*/.match("aaabbb").to_a.should == ["", "", nil]
+    /(a||\2b|())*/.match("aaabbb").to_a.should == ["aaa", "", nil]
+    /(a|\2b||())*/.match("aaabbb").to_a.should == ["aaa", "", nil]
+    /(a|\2b|()|)*/.match("aaabbb").to_a.should == ["aaabbb", "", ""]
+    /(()|a|\3b|())*/.match("aaabbb").to_a.should == ["", "", "", nil]
+    /(a|()|\3b|())*/.match("aaabbb").to_a.should == ["aaa", "", "", nil]
+    /(a|\2b|()|())*/.match("aaabbb").to_a.should == ["aaabbb", "", "", nil]
+    /(a|\3b|()|())*/.match("aaabbb").to_a.should == ["aaa", "", "", nil]
+    /(a|()|())*/.match("aaa").to_a.should == ["aaa", "", "", nil]
+    /^(()|a|())*$/.match("aaa").to_a.should == ["aaa", "", "", nil]
+
+    # Variations with non-greedy loops.
+    /(|a|\2b|())*?/.match("aaabbb").to_a.should == ["", nil, nil]
+    /(a||\2b|())*?/.match("aaabbb").to_a.should == ["", nil, nil]
+    /(a|\2b||())*?/.match("aaabbb").to_a.should == ["", nil, nil]
+    /(a|\2b|()|)*?/.match("aaabbb").to_a.should == ["", nil, nil]
+    /(()|a|\3b|())*?/.match("aaabbb").to_a.should == ["", nil, nil, nil]
+    /(a|()|\3b|())*?/.match("aaabbb").to_a.should == ["", nil, nil, nil]
+    /(a|\2b|()|())*?/.match("aaabbb").to_a.should == ["", nil, nil, nil]
+    /(a|\3b|()|())*?/.match("aaabbb").to_a.should == ["", nil, nil, nil]
+    /(a|()|())*?/.match("aaa").to_a.should == ["", nil, nil, nil]
+    /^(()|a|())*?$/.match("aaa").to_a.should == ["aaa", "a", "", nil]
+  end
+end
diff --git a/spec/ruby/language/regexp/repetition_spec.rb b/spec/ruby/language/regexp/repetition_spec.rb
index 295b3bf553..9a191d74e2 100644
--- a/spec/ruby/language/regexp/repetition_spec.rb
+++ b/spec/ruby/language/regexp/repetition_spec.rb
@@ -128,4 +128,15 @@ describe "Regexps with repetition" do
       RUBY
     end
   end
+
+  it "treats ? after {n} quantifier as another quantifier, not as non-greedy marker" do
+    /a{2}?/.match("").to_a.should == [""]
+  end
+
+  it "matches zero-width capture groups in optional iterations of loops" do
+    /()?/.match("").to_a.should == ["", ""]
+    /(a*)?/.match("").to_a.should == ["", ""]
+    /(a*)*/.match("").to_a.should == ["", ""]
+    /(?:a|()){500,1000}/.match("a" * 500).to_a.should == ["a" * 500, ""]
+  end
 end