Do not have class/module keywords look up ancestors of Object

Fixes case where Object includes a module that defines a constant,
then using class/module keyword to define the same constant on
Object itself.

Implements [Feature #18832]

2 files changed, 15 insertions, 2 deletions

diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index 3dae3916ff..137da09bc3 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -1328,8 +1328,6 @@ class TestModule < Test::Unit::TestCase
       end
     end
     include LangModuleSpecInObject
-    module LangModuleTop
-    end
     puts "ok" if LangModuleSpecInObject::LangModuleTop == LangModuleTop
     INPUT
 
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index 1d7b89de57..b0ad012131 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -1907,6 +1907,21 @@ eom
     assert_equal 0...1, exp.call(a: 0)
   end
 
+  def test_class_module_Object_ancestors
+    assert_separately([], <<-RUBY)
+      m = Module.new
+      m::Bug18832 = 1
+      include m
+      class Bug18832; end
+    RUBY
+    assert_separately([], <<-RUBY)
+      m = Module.new
+      m::Bug18832 = 1
+      include m
+      module Bug18832; end
+    RUBY
+  end
+
   def test_cdhash
     assert_separately([], <<-RUBY)
       n = case 1 when 2r then false else true end