ruby--ruby/spec/ruby/language/keyword_arguments_spec.rb

require_relative '../spec_helper'

ruby_version_is "3.0" do
  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
      it "does not copy a non-empty Hash for a method taking (*args)" do
        def m(*args)
          args[0]
        end

        h = {a: 1}
        m(**h).should.equal?(h)
      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
end