diff --git a/language/method_spec.rb b/language/method_spec.rb
index 21227e914e..0a5bb99d0b 100644
--- a/language/method_spec.rb
+++ b/language/method_spec.rb
@@ -1908,6 +1908,72 @@ def m(...) = mm(...) + mm(...)
       end
     end
   end
+
+  describe "Keyword arguments are now separated from positional arguments" do
+    context "when the method has only positional parameters" do
+      it "treats incoming keyword arguments as positional for compatibility" do
+        def foo(a, b, c, hsh)
+          hsh[:key]
+        end
+
+        foo(1, 2, 3, key: 42).should == 42
+      end
+    end
+
+    context "when the method takes a ** parameter" do
+      it "captures the passed literal keyword arguments" do
+        def foo(a, b, c, **hsh)
+          hsh[:key]
+        end
+
+        foo(1, 2, 3, key: 42).should == 42
+      end
+
+      it "captures the passed ** keyword arguments" do
+        def foo(a, b, c, **hsh)
+          hsh[:key]
+        end
+
+        h = { key: 42 }
+        foo(1, 2, 3, **h).should == 42
+      end
+
+      it "does not convert a positional Hash to keyword arguments" do
+        def foo(a, b, c, **hsh)
+          hsh[:key]
+        end
+
+        -> {
+          foo(1, 2, 3, { key: 42 })
+        }.should raise_error(ArgumentError, 'wrong number of arguments (given 4, expected 3)')
+      end
+    end
+
+    context "when the method takes a key: parameter" do
+      context "when it's called with a positional Hash and no **" do
+        it "raises ArgumentError" do
+          def foo(a, b, c, key: 1)
+            key
+          end
+
+          -> {
+            foo(1, 2, 3, { key: 42 })
+          }.should raise_error(ArgumentError, 'wrong number of arguments (given 4, expected 3)')
+        end
+      end
+
+      context "when it's called with **" do
+        it "captures the passed keyword arguments" do
+          def foo(a, b, c, key: 1)
+            key
+          end
+
+          h = { key: 42 }
+          foo(1, 2, 3, **h).should == 42
+        end
+      end
+    end
+  end
 end
 
 ruby_version_is "3.1" do