Added specs for Module#ruby2_keywords

core/module/ruby2_keywords_spec.rb

@@ -0,0 +1,112 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+ruby_version_is "2.7" do
+  describe "Module.ruby2_keywords" do
+    it "marks the final hash argument as keyword hash" do
+      obj = Object.new
+
+      obj.singleton_class.class_exec do
+        def foo(*a) a.last end
+        ruby2_keywords :foo
+      end
+
+      last = obj.foo(1, 2, a: "a")
+      Hash.ruby2_keywords_hash?(last).should == true
+    end
+
+    ruby_version_is "2.7" ... "3.0" do
+      it "suppresses deprecation warning" do
+        obj = Object.new
+
+        obj.singleton_class.class_exec do
+          def foo(*a) bar(*a) end
+          def bar(*a, **b) end
+        end
+
+        -> { obj.foo(1, 2, {a: "a"}) }.should complain(/Using the last argument as keyword parameters is deprecated/)
+
+        obj.singleton_class.class_exec do
+          ruby2_keywords :foo
+        end
+
+        -> { obj.foo(1, 2, {a: "a"}) }.should_not complain
+      end
+    end
+
+    it "returns nil" do
+      obj = Object.new
+
+      obj.singleton_class.class_exec do
+        def foo(*a) end
+
+        ruby2_keywords(:foo).should == nil
+      end
+    end
+
+    it "raises NameError when passed not existing method name" do
+      obj = Object.new
+
+      -> {
+        obj.singleton_class.class_exec do
+          ruby2_keywords :not_existing
+        end
+      }.should raise_error(NameError, /undefined method `not_existing'/)
+    end
+
+    it "excepts String as well" do
+      obj = Object.new
+
+      obj.singleton_class.class_exec do
+        def foo(*a) a.last end
+        ruby2_keywords "foo"
+      end
+
+      last = obj.foo(1, 2, a: "a")
+      Hash.ruby2_keywords_hash?(last).should == true
+    end
+
+    it "raises TypeError when passed not Symbol or String" do
+      obj = Object.new
+
+      -> {
+        obj.singleton_class.class_exec do
+          ruby2_keywords Object.new
+        end
+      }.should raise_error(TypeError, /is not a symbol nor a string/)
+    end
+
+    it "prints warning when a method does not accept argument splat" do
+      obj = Object.new
+      def obj.foo(a, b, c) end
+
+      -> {
+        obj.singleton_class.class_exec do
+          ruby2_keywords :foo
+        end
+      }.should complain(/Skipping set of ruby2_keywords flag for/)
+    end
+
+    it "prints warning when a method accepts keywords" do
+      obj = Object.new
+      def obj.foo(a:, b:) end
+
+      -> {
+        obj.singleton_class.class_exec do
+          ruby2_keywords :foo
+        end
+      }.should complain(/Skipping set of ruby2_keywords flag for/)
+    end
+
+    it "prints warning when a method accepts keyword splat" do
+      obj = Object.new
+      def obj.foo(**a) end
+
+      -> {
+        obj.singleton_class.class_exec do
+          ruby2_keywords :foo
+        end
+      }.should complain(/Skipping set of ruby2_keywords flag for/)
+    end
+  end
+end