Allow calling a private method with `self.`

This makes it consistent with calling private attribute assignment
methods, which currently is allowed (e.g. `self.value =`).

Calling a private method in this way can be useful when trying to
assign the return value to a local variable with the same name.

[Feature #11297] [Feature #16123]

3 files changed, 4 insertions, 3 deletions

diff --git a/test/ruby/test_method.rb b/test/ruby/test_method.rb
index 1289b44c63..a8064c47c2 100644
--- a/test/ruby/test_method.rb
+++ b/test/ruby/test_method.rb
@@ -673,7 +673,7 @@ class TestMethod < Test::Unit::TestCase
     assert_nothing_raised { mv3 }
 
     assert_nothing_raised { self.mv1 }
-    assert_raise(NoMethodError) { self.mv2 }
+    assert_nothing_raised { self.mv2 }
     assert_nothing_raised { self.mv3 }
 
     v = Visibility.new
diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index 7bb2261ffb..8689c60dcd 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -2479,7 +2479,8 @@ class TestModule < Test::Unit::TestCase
       assert_include(methods, :#{method}, ":#{method} should be private")
 
       assert_raise_with_message(NoMethodError, "private method `#{method}' called for main:Object") {
-        self.#{method}
+        recv = self
+        recv.#{method}
       }
     }
   end
diff --git a/test/ruby/test_refinement.rb b/test/ruby/test_refinement.rb
index 87d60e41a4..4be0720983 100644
--- a/test/ruby/test_refinement.rb
+++ b/test/ruby/test_refinement.rb
@@ -538,7 +538,7 @@ class TestRefinement < Test::Unit::TestCase
 
   def test_main_using_is_private
     assert_raise(NoMethodError) do
-      eval("self.using Module.new", Sandbox::BINDING)
+      eval("recv = self; recv.using Module.new", Sandbox::BINDING)
     end
   end