Make constantize look down the ancestor chain (excluding Object)

2 files changed, 30 insertions, 1 deletions

diff --git a/activesupport/lib/active_support/inflector/methods.rb b/activesupport/lib/active_support/inflector/methods.rb
index 48296841aa..274dc90eff 100644
--- a/activesupport/lib/active_support/inflector/methods.rb
+++ b/activesupport/lib/active_support/inflector/methods.rb
@@ -203,7 +203,19 @@ module ActiveSupport
       names.shift if names.empty? || names.first.empty?
 
       names.inject(Object) do |constant, name|
-        constant.const_get(name, false)
+        candidate = constant.const_get(name)
+        if constant.const_defined?(name, false) || !Object.const_defined?(name)
+          candidate
+        else
+          # Go down the ancestors to check it it's owned
+          # directly before we reach Object or the end of ancestors.
+          constant.ancestors.each do |ancestor|
+            break if ancestor == Object
+            return candidate if ancestor.const_defined?(name, false)
+          end
+          # owner is in Object, so raise
+          constant.const_get(name, false)
+        end
       end
     end
 
diff --git a/activesupport/test/constantize_test_cases.rb b/activesupport/test/constantize_test_cases.rb
index 135f894056..908f9e9a37 100644
--- a/activesupport/test/constantize_test_cases.rb
+++ b/activesupport/test/constantize_test_cases.rb
@@ -1,7 +1,14 @@
 module Ace
   module Base
     class Case
+      class Dice
+      end
     end
+    class Fase < Case
+    end
+  end
+  class Gas
+    include Base
   end
 end
 
@@ -9,6 +16,9 @@ module ConstantizeTestCases
   def run_constantize_tests_on
     assert_nothing_raised { assert_equal Ace::Base::Case, yield("Ace::Base::Case") }
     assert_nothing_raised { assert_equal Ace::Base::Case, yield("::Ace::Base::Case") }
+    assert_nothing_raised { assert_equal Ace::Base::Case::Dice, yield("Ace::Base::Case::Dice") }
+    assert_nothing_raised { assert_equal Ace::Base::Fase::Dice, yield("Ace::Base::Fase::Dice") }
+    assert_nothing_raised { assert_equal Ace::Gas::Case, yield("Ace::Gas::Case") }
     assert_nothing_raised { assert_equal ConstantizeTestCases, yield("ConstantizeTestCases") }
     assert_nothing_raised { assert_equal ConstantizeTestCases, yield("::ConstantizeTestCases") }
     assert_raise(NameError) { yield("UnknownClass") }
@@ -18,11 +28,16 @@ module ConstantizeTestCases
     assert_raise(NameError) { yield("InvalidClass\n") }
     assert_raise(NameError) { yield("Ace::ConstantizeTestCases") }
     assert_raise(NameError) { yield("Ace::Base::ConstantizeTestCases") }
+    assert_raise(NameError) { yield("Ace::Gas::Base") }
+    assert_raise(NameError) { yield("Ace::Gas::ConstantizeTestCases") }
   end
 
   def run_safe_constantize_tests_on
     assert_nothing_raised { assert_equal Ace::Base::Case, yield("Ace::Base::Case") }
     assert_nothing_raised { assert_equal Ace::Base::Case, yield("::Ace::Base::Case") }
+    assert_nothing_raised { assert_equal Ace::Base::Case::Dice, yield("Ace::Base::Case::Dice") }
+    assert_nothing_raised { assert_equal Ace::Base::Fase::Dice, yield("Ace::Base::Fase::Dice") }
+    assert_nothing_raised { assert_equal Ace::Gas::Case, yield("Ace::Gas::Case") }
     assert_nothing_raised { assert_equal ConstantizeTestCases, yield("ConstantizeTestCases") }
     assert_nothing_raised { assert_equal ConstantizeTestCases, yield("::ConstantizeTestCases") }
     assert_nothing_raised { assert_equal nil, yield("UnknownClass") }
@@ -33,6 +48,8 @@ module ConstantizeTestCases
     assert_nothing_raised { assert_equal nil, yield("blargle") }
     assert_nothing_raised { assert_equal nil, yield("Ace::ConstantizeTestCases") }
     assert_nothing_raised { assert_equal nil, yield("Ace::Base::ConstantizeTestCases") }
+    assert_nothing_raised { assert_equal nil, yield("Ace::Gas::Base") }
+    assert_nothing_raised { assert_equal nil, yield("Ace::Gas::ConstantizeTestCases") }
     assert_nothing_raised { assert_equal nil, yield("#<Class:0x7b8b718b>::Nested_1") }
   end
 end