Add AM test for after_validation returning false

This stems from https://github.com/rails/rails/pull/17227#discussion_r21641358

It's simply a clarification of the current behavior by which if an
`after_validation` ActiveModel callback returns +false+, then further
`after_` callbacks **are not halted**.

1 files changed, 13 insertions, 2 deletions

diff --git a/activemodel/test/cases/validations/callbacks_test.rb b/activemodel/test/cases/validations/callbacks_test.rb
index 6cd0f4ed4d..5d6d48b824 100644
--- a/activemodel/test/cases/validations/callbacks_test.rb
+++ b/activemodel/test/cases/validations/callbacks_test.rb
@@ -30,11 +30,16 @@ class DogWithTwoValidators < Dog
   before_validation { self.history << 'before_validation_marker2' }
 end
 
-class DogValidatorReturningFalse < Dog
+class DogBeforeValidatorReturningFalse < Dog
   before_validation { false }
   before_validation { self.history << 'before_validation_marker2' }
 end
 
+class DogAfterValidatorReturningFalse < Dog
+  after_validation { false }
+  after_validation { self.history << 'after_validation_marker' }
+end
+
 class DogWithMissingName < Dog
   before_validation { self.history << 'before_validation_marker' }
   validates_presence_of :name
@@ -82,12 +87,18 @@ class CallbacksWithMethodNamesShouldBeCalled < ActiveModel::TestCase
   end
 
   def test_further_callbacks_should_not_be_called_if_before_validation_returns_false
-    d = DogValidatorReturningFalse.new
+    d = DogBeforeValidatorReturningFalse.new
     output = d.valid?
     assert_equal [], d.history
     assert_equal false, output
   end
 
+  def test_further_callbacks_should_be_called_if_after_validation_returns_false
+    d = DogAfterValidatorReturningFalse.new
+    d.valid?
+    assert_equal ['after_validation_marker'], d.history
+  end
+
   def test_validation_test_should_be_done
     d = DogWithMissingName.new
     output = d.valid?