Merge pull request #9042 from senny/9034_float_0_0_is_always_dirty

Assigning '0.0' to a nullable numeric column does not make it dirty

Example:
    product = Product.create price: 0.0
    product.price = '0.0'
    product.changed? # => false (this used to return true)
    product.changes # => {} (this used to return { price: [0.0, 0.0] })

1 files changed, 5 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/attribute_methods/dirty.rb b/activerecord/lib/active_record/attribute_methods/dirty.rb
index 616ae1631f..6315dd9549 100644
--- a/activerecord/lib/active_record/attribute_methods/dirty.rb
+++ b/activerecord/lib/active_record/attribute_methods/dirty.rb
@@ -107,7 +107,11 @@ module ActiveRecord
 
       def changes_from_zero_to_string?(old, value)
         # For columns with old 0 and value non-empty string
-        old == 0 && value.is_a?(String) && value.present? && value != '0'
+        old == 0 && value.is_a?(String) && value.present? && non_zero?(value)
+      end
+
+      def non_zero?(value)
+        value !~ /\A0+(\.0+)?\z/
       end
     end
   end