Ensure `false` is preserved in attr serialization

2 files changed, 9 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/attribute.rb b/activerecord/lib/active_record/attribute.rb
index 38281158d8..78662433eb 100644
--- a/activerecord/lib/active_record/attribute.rb
+++ b/activerecord/lib/active_record/attribute.rb
@@ -122,7 +122,7 @@ module ActiveRecord
 
     def encode_with(coder)
       coder["name"] = name
-      coder["value_before_type_cast"] = value_before_type_cast if value_before_type_cast
+      coder["value_before_type_cast"] = value_before_type_cast unless value_before_type_cast.nil?
       coder["type"] = type if type
       coder["original_attribute"] = original_attribute if original_attribute
       coder["value"] = value if defined?(@value)
diff --git a/activerecord/test/cases/yaml_serialization_test.rb b/activerecord/test/cases/yaml_serialization_test.rb
index bfc13d683d..dd8d2c1178 100644
--- a/activerecord/test/cases/yaml_serialization_test.rb
+++ b/activerecord/test/cases/yaml_serialization_test.rb
@@ -119,6 +119,14 @@ class YamlSerializationTest < ActiveRecord::TestCase
     assert_equal author.changes, dumped.changes
   end
 
+  def test_yaml_encoding_keeps_false_values
+    topic = Topic.first
+    topic.approved = false
+    dumped = YAML.load(YAML.dump(topic))
+
+    assert_equal false, dumped.approved
+  end
+
   private
 
     def yaml_fixture(file_name)