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, 15 insertions, 0 deletions

diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb
index c7d2ba6073..7b2034dadf 100644
--- a/activerecord/test/cases/dirty_test.rb
+++ b/activerecord/test/cases/dirty_test.rb
@@ -243,6 +243,21 @@ class DirtyTest < ActiveRecord::TestCase
     assert !pirate.changed?
   end
 
+  def test_float_zero_to_string_zero_not_marked_as_changed
+    data = NumericData.new :temperature => 0.0
+    data.save!
+
+    assert_not data.changed?
+
+    data.temperature = '0'
+    assert_empty data.changes
+
+    data.temperature = '0.0'
+    assert_empty data.changes
+
+    data.temperature = '0.00'
+    assert_empty data.changes
+  end
 
   def test_zero_to_blank_marked_as_changed
     pirate = Pirate.new