[ruby/mutex_m] Fix `Mutex_m#initialize` when the super's initialize has kwargs

Co-authored-by: Ryuta Kamizono <kamipo@gmail.com>

https://github.com/ruby/mutex_m/commit/84ca1fc108

2 files changed, 33 insertions, 0 deletions

diff --git a/lib/mutex_m.rb b/lib/mutex_m.rb
index dd47934bea..07f5a9a0a0 100644
--- a/lib/mutex_m.rb
+++ b/lib/mutex_m.rb
@@ -113,4 +113,5 @@ module Mutex_m
     mu_initialize
     super
   end
+  ruby2_keywords(:initialize) if respond_to?(:ruby2_keywords, true)
 end
diff --git a/test/test_mutex_m.rb b/test/test_mutex_m.rb
index 30971dd352..e5cfbc8b5f 100644
--- a/test/test_mutex_m.rb
+++ b/test/test_mutex_m.rb
@@ -23,4 +23,36 @@ class TestMutexM < Test::Unit::TestCase
     c.signal
     assert_equal "abc", t.value
   end
+
+  class KeywordInitializeParent
+    def initialize(x:)
+    end
+  end
+
+  class KeywordInitializeChild < KeywordInitializeParent
+    include Mutex_m
+    def initialize
+      super(x: 1)
+    end
+  end
+
+  def test_initialize_with_keyword_arg
+    assert KeywordInitializeChild.new
+  end
+
+  class NoArgInitializeParent
+    def initialize
+    end
+  end
+
+  class NoArgInitializeChild < NoArgInitializeParent
+    include Mutex_m
+    def initialize
+      super()
+    end
+  end
+
+  def test_initialize_no_args
+    assert NoArgInitializeChild.new
+  end
 end