1 files changed, 398 insertions, 0 deletions
diff --git a/spec/ruby/language/keyword_arguments_spec.rb b/spec/ruby/language/keyword_arguments_spec.rb
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+++ b/spec/ruby/language/keyword_arguments_spec.rb
@@ -0,0 +1,398 @@
+require_relative '../spec_helper'
+
+describe "Keyword arguments" do
+  def target(*args, **kwargs)
+    [args, kwargs]
+  end
+
+  it "are separated from positional arguments" do
+    def m(*args, **kwargs)
+      [args, kwargs]
+    end
+
+    empty = {}
+    m(**empty).should == [[], {}]
+    m(empty).should == [[{}], {}]
+
+    m(a: 1).should == [[], {a: 1}]
+    m({a: 1}).should == [[{a: 1}], {}]
+  end
+
+  it "when the receiving method has not keyword parameters it treats kwargs as positional" do
+    def m(*a)
+      a
+    end
+
+    m(a: 1).should == [{a: 1}]
+    m({a: 1}).should == [{a: 1}]
+  end
+
+  context "empty kwargs are treated as if they were not passed" do
+    it "when calling a method" do
+      def m(*a)
+        a
+      end
+
+      empty = {}
+      m(**empty).should == []
+      m(empty).should == [{}]
+    end
+
+    it "when yielding to a block" do
+      def y(*args, **kwargs)
+        yield(*args, **kwargs)
+      end
+
+      empty = {}
+      y(**empty) { |*a| a }.should == []
+      y(empty) { |*a| a }.should == [{}]
+    end
+  end
+
+  it "extra keywords are not allowed without **kwrest" do
+    def m(*a, kw:)
+      a
+    end
+
+    m(kw: 1).should == []
+    -> { m(kw: 1, kw2: 2) }.should raise_error(ArgumentError, 'unknown keyword: :kw2')
+    -> { m(kw: 1, true => false) }.should raise_error(ArgumentError, 'unknown keyword: true')
+    -> { m(kw: 1, a: 1, b: 2, c: 3) }.should raise_error(ArgumentError, 'unknown keywords: :a, :b, :c')
+  end
+
+  it "raises ArgumentError exception when required keyword argument is not passed" do
+    def m(a:, b:, c:)
+      [a, b, c]
+    end
+
+    -> { m(a: 1, b: 2) }.should raise_error(ArgumentError, /missing keyword: :c/)
+    -> { m() }.should raise_error(ArgumentError, /missing keywords: :a, :b, :c/)
+  end
+
+  it "raises ArgumentError for missing keyword arguments even if there are extra ones" do
+    def m(a:)
+      a
+    end
+
+    -> { m(b: 1) }.should raise_error(ArgumentError, /missing keyword: :a/)
+  end
+
+  it "handle * and ** at the same call site" do
+    def m(*a)
+      a
+    end
+
+    m(*[], **{}).should == []
+    m(*[], 42, **{}).should == [42]
+  end
+
+  context "**" do
+    ruby_version_is "3.3" do
+      it "copies a non-empty Hash for a method taking (*args)" do
+        def m(*args)
+          args[0]
+        end
+
+        h = {a: 1}
+        m(**h).should_not.equal?(h)
+        h.should == {a: 1}
+      end
+    end
+
+    it "copies the given Hash for a method taking (**kwargs)" do
+      def m(**kw)
+        kw
+      end
+
+      empty = {}
+      m(**empty).should == empty
+      m(**empty).should_not.equal?(empty)
+
+      h = {a: 1}
+      m(**h).should == h
+      m(**h).should_not.equal?(h)
+    end
+  end
+
+  context "delegation" do
+    it "works with (*args, **kwargs)" do
+      def m(*args, **kwargs)
+        target(*args, **kwargs)
+      end
+
+      empty = {}
+      m(**empty).should == [[], {}]
+      m(empty).should == [[{}], {}]
+
+      m(a: 1).should == [[], {a: 1}]
+      m({a: 1}).should == [[{a: 1}], {}]
+    end
+
+    it "works with proc { |*args, **kwargs| }" do
+      m = proc do |*args, **kwargs|
+        target(*args, **kwargs)
+      end
+
+      empty = {}
+      m.(**empty).should == [[], {}]
+      m.(empty).should == [[{}], {}]
+
+      m.(a: 1).should == [[], {a: 1}]
+      m.({a: 1}).should == [[{a: 1}], {}]
+
+      # no autosplatting for |*args, **kwargs|
+      m.([1, 2]).should == [[[1, 2]], {}]
+    end
+
+    it "works with -> (*args, **kwargs) {}" do
+      m = -> *args, **kwargs do
+        target(*args, **kwargs)
+      end
+
+      empty = {}
+      m.(**empty).should == [[], {}]
+      m.(empty).should == [[{}], {}]
+
+      m.(a: 1).should == [[], {a: 1}]
+      m.({a: 1}).should == [[{a: 1}], {}]
+    end
+
+    it "works with (...)" do
+      instance_eval <<~DEF
+      def m(...)
+        target(...)
+      end
+      DEF
+
+      empty = {}
+      m(**empty).should == [[], {}]
+      m(empty).should == [[{}], {}]
+
+      m(a: 1).should == [[], {a: 1}]
+      m({a: 1}).should == [[{a: 1}], {}]
+    end
+
+    it "works with call(*ruby2_keyword_args)" do
+      class << self
+        ruby2_keywords def m(*args)
+          target(*args)
+        end
+      end
+
+      empty = {}
+      m(**empty).should == [[], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+      m(empty).should == [[{}], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+
+      m(a: 1).should == [[], {a: 1}]
+      m({a: 1}).should == [[{a: 1}], {}]
+
+      kw = {a: 1}
+
+      m(**kw).should == [[], {a: 1}]
+      m(**kw)[1].should == kw
+      m(**kw)[1].should_not.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+      Hash.ruby2_keywords_hash?(m(**kw)[1]).should == false
+
+      m(kw).should == [[{a: 1}], {}]
+      m(kw)[0][0].should.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+    end
+
+    it "works with super(*ruby2_keyword_args)" do
+      parent = Class.new do
+        def m(*args, **kwargs)
+          [args, kwargs]
+        end
+      end
+
+      child = Class.new(parent) do
+        ruby2_keywords def m(*args)
+          super(*args)
+        end
+      end
+
+      obj = child.new
+
+      empty = {}
+      obj.m(**empty).should == [[], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+      obj.m(empty).should == [[{}], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+
+      obj.m(a: 1).should == [[], {a: 1}]
+      obj.m({a: 1}).should == [[{a: 1}], {}]
+
+      kw = {a: 1}
+
+      obj.m(**kw).should == [[], {a: 1}]
+      obj.m(**kw)[1].should == kw
+      obj.m(**kw)[1].should_not.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+      Hash.ruby2_keywords_hash?(obj.m(**kw)[1]).should == false
+
+      obj.m(kw).should == [[{a: 1}], {}]
+      obj.m(kw)[0][0].should.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+    end
+
+    it "works with zsuper" do
+      parent = Class.new do
+        def m(*args, **kwargs)
+          [args, kwargs]
+        end
+      end
+
+      child = Class.new(parent) do
+        ruby2_keywords def m(*args)
+          super
+        end
+      end
+
+      obj = child.new
+
+      empty = {}
+      obj.m(**empty).should == [[], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+      obj.m(empty).should == [[{}], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+
+      obj.m(a: 1).should == [[], {a: 1}]
+      obj.m({a: 1}).should == [[{a: 1}], {}]
+
+      kw = {a: 1}
+
+      obj.m(**kw).should == [[], {a: 1}]
+      obj.m(**kw)[1].should == kw
+      obj.m(**kw)[1].should_not.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+      Hash.ruby2_keywords_hash?(obj.m(**kw)[1]).should == false
+
+      obj.m(kw).should == [[{a: 1}], {}]
+      obj.m(kw)[0][0].should.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+    end
+
+    it "works with yield(*ruby2_keyword_args)" do
+      class << self
+        def y(args)
+          yield(*args)
+        end
+
+        ruby2_keywords def m(*outer_args)
+          y(outer_args, &-> *args, **kwargs { target(*args, **kwargs) })
+        end
+      end
+
+      empty = {}
+      m(**empty).should == [[], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+      m(empty).should == [[{}], {}]
+      Hash.ruby2_keywords_hash?(empty).should == false
+
+      m(a: 1).should == [[], {a: 1}]
+      m({a: 1}).should == [[{a: 1}], {}]
+
+      kw = {a: 1}
+
+      m(**kw).should == [[], {a: 1}]
+      m(**kw)[1].should == kw
+      m(**kw)[1].should_not.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+      Hash.ruby2_keywords_hash?(m(**kw)[1]).should == false
+
+      m(kw).should == [[{a: 1}], {}]
+      m(kw)[0][0].should.equal?(kw)
+      Hash.ruby2_keywords_hash?(kw).should == false
+    end
+
+    it "does not work with (*args)" do
+      class << self
+        def m(*args)
+          target(*args)
+        end
+      end
+
+      empty = {}
+      m(**empty).should == [[], {}]
+      m(empty).should == [[{}], {}]
+
+      m(a: 1).should == [[{a: 1}], {}]
+      m({a: 1}).should == [[{a: 1}], {}]
+    end
+
+    ruby_version_is "3.1" do
+      describe "omitted values" do
+        it "accepts short notation 'key' for 'key: value' syntax" do
+          def m(a:, b:)
+            [a, b]
+          end
+
+          a = 1
+          b = 2
+
+          eval('m(a:, b:).should == [1, 2]')
+        end
+      end
+    end
+
+    ruby_version_is "3.2" do
+      it "does not work with call(*ruby2_keyword_args) with missing ruby2_keywords in between" do
+        class << self
+          def n(*args) # Note the missing ruby2_keywords here
+            target(*args)
+          end
+
+          ruby2_keywords def m(*args)
+            n(*args)
+          end
+        end
+
+        empty = {}
+        m(**empty).should == [[], {}]
+        m(empty).should == [[{}], {}]
+
+        m(a: 1).should == [[{a: 1}], {}]
+        m({a: 1}).should == [[{a: 1}], {}]
+      end
+    end
+
+    ruby_version_is ""..."3.2" do
+      # https://bugs.ruby-lang.org/issues/18625
+      it "works with call(*ruby2_keyword_args) with missing ruby2_keywords in between due to CRuby bug #18625" do
+        class << self
+          def n(*args) # Note the missing ruby2_keywords here
+            target(*args)
+          end
+
+          ruby2_keywords def m(*args)
+            n(*args)
+          end
+        end
+
+        empty = {}
+        m(**empty).should == [[], {}]
+        Hash.ruby2_keywords_hash?(empty).should == false
+        m(empty).should == [[{}], {}]
+        Hash.ruby2_keywords_hash?(empty).should == false
+
+        m(a: 1).should == [[], {a: 1}]
+        m({a: 1}).should == [[{a: 1}], {}]
+
+        kw = {a: 1}
+
+        m(**kw).should == [[], {a: 1}]
+        m(**kw)[1].should == kw
+        m(**kw)[1].should_not.equal?(kw)
+        Hash.ruby2_keywords_hash?(kw).should == false
+        Hash.ruby2_keywords_hash?(m(**kw)[1]).should == false
+
+        m(kw).should == [[{a: 1}], {}]
+        m(kw)[0][0].should.equal?(kw)
+        Hash.ruby2_keywords_hash?(kw).should == false
+      end
+    end
+  end
+end