Add in-tree mspec and ruby/spec

* For easier modifications of ruby/spec by MRI developers.
* .gitignore: track changes under spec.
* spec/mspec, spec/rubyspec: add in-tree mspec and ruby/spec.
  These files can therefore be updated like any other file in MRI.
  Instructions are provided in spec/README.
  [Feature #13156] [ruby-core:79246]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58595 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 573 insertions, 0 deletions

diff --git a/spec/rubyspec/language/lambda_spec.rb b/spec/rubyspec/language/lambda_spec.rb
new file mode 100644
index 0000000000..43e2d60ae3
--- /dev/null
+++ b/spec/rubyspec/language/lambda_spec.rb
@@ -0,0 +1,573 @@
+require File.expand_path('../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "A lambda literal -> () { }" do
+  SpecEvaluate.desc = "for definition"
+
+  it "returns a Proc object when used in a BasicObject method" do
+    klass = Class.new(BasicObject) do
+      def create_lambda
+        -> () { }
+      end
+    end
+
+    klass.new.create_lambda.should be_an_instance_of(Proc)
+  end
+
+  it "does not execute the block" do
+    ->() { fail }.should be_an_instance_of(Proc)
+  end
+
+  it "returns a lambda" do
+    -> () { }.lambda?.should be_true
+  end
+
+  it "has its own scope for local variables" do
+    l = -> arg {
+      var = arg
+      # this would override var if it was declared outside the lambda
+      l.call(arg-1) if arg > 0
+      var
+    }
+    l.call(1).should == 1
+  end
+
+  context "assigns no local variables" do
+    evaluate <<-ruby do
+        @a = -> { }
+        @b = ->() { }
+        @c = -> () { }
+        @d = -> do end
+      ruby
+
+      @a.().should be_nil
+      @b.().should be_nil
+      @c.().should be_nil
+      @d.().should be_nil
+    end
+  end
+
+  context "assigns variables from parameters" do
+    evaluate <<-ruby do
+        @a = -> (a) { a }
+      ruby
+
+      @a.(1).should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = -> ((a)) { a }
+      ruby
+
+      @a.(1).should == 1
+      @a.([1, 2, 3]).should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = -> ((*a, b)) { [a, b] }
+      ruby
+
+      @a.(1).should == [[], 1]
+      @a.([1, 2, 3]).should == [[1, 2], 3]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a={}) { a }
+      ruby
+
+      @a.().should == {}
+      @a.(2).should == 2
+    end
+
+    evaluate <<-ruby do
+        @a = -> (*) { }
+      ruby
+
+      @a.().should be_nil
+      @a.(1).should be_nil
+      @a.(1, 2, 3).should be_nil
+    end
+
+    evaluate <<-ruby do
+        @a = -> (*a) { a }
+      ruby
+
+      @a.().should == []
+      @a.(1).should == [1]
+      @a.(1, 2, 3).should == [1, 2, 3]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a:) { a }
+      ruby
+
+      lambda { @a.() }.should raise_error(ArgumentError)
+      @a.(a: 1).should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a: 1) { a }
+      ruby
+
+      @a.().should == 1
+      @a.(a: 2).should == 2
+    end
+
+    evaluate <<-ruby do
+        @a = -> (**) {  }
+      ruby
+
+      @a.().should be_nil
+      @a.(a: 1, b: 2).should be_nil
+      lambda { @a.(1) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        @a = -> (**k) { k }
+      ruby
+
+      @a.().should == {}
+      @a.(a: 1, b: 2).should == {a: 1, b: 2}
+    end
+
+    evaluate <<-ruby do
+        @a = -> (&b) { b  }
+      ruby
+
+      @a.().should be_nil
+      @a.() { }.should be_an_instance_of(Proc)
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a, b) { [a, b] }
+      ruby
+
+      @a.(1, 2).should == [1, 2]
+      lambda { @a.() }.should raise_error(ArgumentError)
+      lambda { @a.(1) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        @a = -> ((a, b, *c, d), (*e, f, g), (*h)) do
+          [a, b, c, d, e, f, g, h]
+        end
+      ruby
+
+      @a.(1, 2, 3).should == [1, nil, [], nil, [], 2, nil, [3]]
+      result = @a.([1, 2, 3], [4, 5, 6, 7, 8], [9, 10])
+      result.should == [1, 2, [], 3, [4, 5, 6], 7, 8, [9, 10]]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a, (b, (c, *d, (e, (*f)), g), (h, (i, j)))) do
+          [a, b, c, d, e, f, g, h, i, j]
+        end
+      ruby
+
+      @a.(1, 2).should == [1, 2, nil, [], nil, [nil], nil, nil, nil, nil]
+      result = @a.(1, [2, [3, 4, 5, [6, [7, 8]], 9], [10, [11, 12]]])
+      result.should == [1, 2, 3, [4, 5], 6, [7, 8], 9, 10, 11, 12]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (*, **k) { k }
+      ruby
+
+      @a.().should == {}
+      @a.(1, 2, 3, a: 4, b: 5).should == {a: 4, b: 5}
+
+      h = mock("keyword splat")
+      h.should_receive(:to_hash).and_return({a: 1})
+      @a.(h).should == {a: 1}
+    end
+
+    evaluate <<-ruby do
+        @a = -> (*, &b) { b }
+      ruby
+
+      @a.().should be_nil
+      @a.(1, 2, 3, 4).should be_nil
+      @a.(&(l = ->{})).should equal(l)
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a:, b:) { [a, b] }
+      ruby
+
+      @a.(a: 1, b: 2).should == [1, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a:, b: 1) { [a, b] }
+      ruby
+
+      @a.(a: 1).should == [1, 1]
+      @a.(a: 1, b: 2).should == [1, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a: 1, b:) { [a, b] }
+      ruby
+
+      @a.(b: 0).should == [1, 0]
+      @a.(b: 2, a: 3).should == [3, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a: @a = -> (a: 1) { a }, b:) do
+          [a, b]
+        end
+      ruby
+
+      @a.(a: 2, b: 3).should == [2, 3]
+      @a.(b: 1).should == [@a, 1]
+
+      # Note the default value of a: in the original method.
+      @a.().should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a: 1, b: 2) { [a, b] }
+      ruby
+
+      @a.().should == [1, 2]
+      @a.(b: 3, a: 4).should == [4, 3]
+    end
+
+    evaluate <<-ruby do
+        @a = -> (a, b=1, *c, (*d, (e)), f: 2, g:, h:, **k, &l) do
+          [a, b, c, d, e, f, g, h, k, l]
+        end
+      ruby
+
+      result = @a.(9, 8, 7, 6, f: 5, g: 4, h: 3, &(l = ->{}))
+      result.should == [9, 8, [7], [], 6, 5, 4, 3, {}, l]
+    end
+
+    evaluate <<-ruby do
+        @a = -> a, b=1, *c, d, e:, f: 2, g:, **k, &l do
+          [a, b, c, d, e, f, g, k, l]
+        end
+      ruby
+
+      result = @a.(1, 2, e: 3, g: 4, h: 5, i: 6, &(l = ->{}))
+      result.should == [1, 1, [], 2, 3, 2, 4, { h: 5, i: 6 }, l]
+    end
+
+    describe "with circular optional argument reference" do
+      it "shadows an existing local with the same name as the argument" do
+        a = 1
+        -> {
+          @proc = eval "-> (a=a) { a }"
+        }.should complain(/circular argument reference/)
+        @proc.call.should == nil
+      end
+
+      it "shadows an existing method with the same name as the argument" do
+        def a; 1; end
+        -> {
+          @proc = eval "-> (a=a) { a }"
+        }.should complain(/circular argument reference/)
+        @proc.call.should == nil
+      end
+
+      it "calls an existing method with the same name as the argument if explicitly using ()" do
+        def a; 1; end
+        -> (a=a()) { a }.call.should == 1
+      end
+    end
+  end
+end
+
+describe "A lambda expression 'lambda { ... }'" do
+  SpecEvaluate.desc = "for definition"
+
+  it "calls the #lambda method" do
+    obj = mock("lambda definition")
+    obj.should_receive(:lambda).and_return(obj)
+
+    def obj.define
+      lambda { }
+    end
+
+    obj.define.should equal(obj)
+  end
+
+  it "does not execute the block" do
+    lambda { fail }.should be_an_instance_of(Proc)
+  end
+
+  it "returns a lambda" do
+    lambda { }.lambda?.should be_true
+  end
+
+  it "requires a block" do
+    lambda { lambda }.should raise_error(ArgumentError)
+  end
+
+  context "with an implicit block" do
+    before do
+      def meth; lambda; end
+    end
+
+    it "can be created" do
+      implicit_lambda = nil
+      -> {
+        implicit_lambda = meth { 1 }
+      }.should complain(/tried to create Proc object without a block/)
+
+      implicit_lambda.lambda?.should be_true
+      implicit_lambda.call.should == 1
+    end
+  end
+
+  context "assigns no local variables" do
+    evaluate <<-ruby do
+        @a = lambda { }
+        @b = lambda { || }
+      ruby
+
+      @a.().should be_nil
+      @b.().should be_nil
+    end
+  end
+
+  context "assigns variables from parameters" do
+    evaluate <<-ruby do
+        @a = lambda { |a| a }
+      ruby
+
+      @a.(1).should == 1
+    end
+
+    evaluate <<-ruby do
+        def m(*a) yield(*a) end
+        @a = lambda { |a| a }
+      ruby
+
+      lambda { m(&@a) }.should raise_error(ArgumentError)
+      lambda { m(1, 2, &@a) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a, | a }
+      ruby
+
+      @a.(1).should == 1
+      @a.([1, 2]).should == [1, 2]
+
+      lambda { @a.() }.should raise_error(ArgumentError)
+      lambda { @a.(1, 2) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        def m(a) yield a end
+        def m2() yield end
+
+        @a = lambda { |a, | a }
+      ruby
+
+      m(1, &@a).should == 1
+      m([1, 2], &@a).should == [1, 2]
+
+      lambda { m2(&@a) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |(a)| a }
+      ruby
+
+      @a.(1).should == 1
+      @a.([1, 2, 3]).should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |(*a, b)| [a, b] }
+      ruby
+
+      @a.(1).should == [[], 1]
+      @a.([1, 2, 3]).should == [[1, 2], 3]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a={}| a }
+      ruby
+
+      @a.().should == {}
+      @a.(2).should == 2
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |*| }
+      ruby
+
+      @a.().should be_nil
+      @a.(1).should be_nil
+      @a.(1, 2, 3).should be_nil
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |*a| a }
+      ruby
+
+      @a.().should == []
+      @a.(1).should == [1]
+      @a.(1, 2, 3).should == [1, 2, 3]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a:| a }
+      ruby
+
+      lambda { @a.() }.should raise_error(ArgumentError)
+      @a.(a: 1).should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a: 1| a }
+      ruby
+
+      @a.().should == 1
+      @a.(a: 2).should == 2
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |**|  }
+      ruby
+
+      @a.().should be_nil
+      @a.(a: 1, b: 2).should be_nil
+      lambda { @a.(1) }.should raise_error(ArgumentError)
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |**k| k }
+      ruby
+
+      @a.().should == {}
+      @a.(a: 1, b: 2).should == {a: 1, b: 2}
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |&b| b  }
+      ruby
+
+      @a.().should be_nil
+      @a.() { }.should be_an_instance_of(Proc)
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a, b| [a, b] }
+      ruby
+
+      @a.(1, 2).should == [1, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda do |(a, b, *c, d), (*e, f, g), (*h)|
+          [a, b, c, d, e, f, g, h]
+        end
+      ruby
+
+      @a.(1, 2, 3).should == [1, nil, [], nil, [], 2, nil, [3]]
+      result = @a.([1, 2, 3], [4, 5, 6, 7, 8], [9, 10])
+      result.should == [1, 2, [], 3, [4, 5, 6], 7, 8, [9, 10]]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda do |a, (b, (c, *d, (e, (*f)), g), (h, (i, j)))|
+          [a, b, c, d, e, f, g, h, i, j]
+        end
+      ruby
+
+      @a.(1, 2).should == [1, 2, nil, [], nil, [nil], nil, nil, nil, nil]
+      result = @a.(1, [2, [3, 4, 5, [6, [7, 8]], 9], [10, [11, 12]]])
+      result.should == [1, 2, 3, [4, 5], 6, [7, 8], 9, 10, 11, 12]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |*, **k| k }
+      ruby
+
+      @a.().should == {}
+      @a.(1, 2, 3, a: 4, b: 5).should == {a: 4, b: 5}
+
+      h = mock("keyword splat")
+      h.should_receive(:to_hash).and_return({a: 1})
+      @a.(h).should == {a: 1}
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |*, &b| b }
+      ruby
+
+      @a.().should be_nil
+      @a.(1, 2, 3, 4).should be_nil
+      @a.(&(l = ->{})).should equal(l)
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a:, b:| [a, b] }
+      ruby
+
+      @a.(a: 1, b: 2).should == [1, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a:, b: 1| [a, b] }
+      ruby
+
+      @a.(a: 1).should == [1, 1]
+      @a.(a: 1, b: 2).should == [1, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a: 1, b:| [a, b] }
+      ruby
+
+      @a.(b: 0).should == [1, 0]
+      @a.(b: 2, a: 3).should == [3, 2]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda do |a: (@a = -> (a: 1) { a }), b:|
+          [a, b]
+        end
+      ruby
+
+      @a.(a: 2, b: 3).should == [2, 3]
+      @a.(b: 1).should == [@a, 1]
+
+      # Note the default value of a: in the original method.
+      @a.().should == 1
+    end
+
+    evaluate <<-ruby do
+        @a = lambda { |a: 1, b: 2| [a, b] }
+      ruby
+
+      @a.().should == [1, 2]
+      @a.(b: 3, a: 4).should == [4, 3]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda do |a, b=1, *c, (*d, (e)), f: 2, g:, h:, **k, &l|
+          [a, b, c, d, e, f, g, h, k, l]
+        end
+      ruby
+
+      result = @a.(9, 8, 7, 6, f: 5, g: 4, h: 3, &(l = ->{}))
+      result.should == [9, 8, [7], [], 6, 5, 4, 3, {}, l]
+    end
+
+    evaluate <<-ruby do
+        @a = lambda do |a, b=1, *c, d, e:, f: 2, g:, **k, &l|
+          [a, b, c, d, e, f, g, k, l]
+        end
+      ruby
+
+      result = @a.(1, 2, e: 3, g: 4, h: 5, i: 6, &(l = ->{}))
+      result.should == [1, 1, [], 2, 3, 2, 4, { h: 5, i: 6 }, l]
+    end
+  end
+end