Fix `Type::Date#serialize` to return a date object correctly

Currently `Type::Date#serialize` does not cast a value to a date object.
It should be cast to a date object for finding by date column correctly
working.

Fixes #25354.

2 files changed, 17 insertions, 1 deletions

diff --git a/activemodel/lib/active_model/type/date.rb b/activemodel/lib/active_model/type/date.rb
index f74243a22c..edd07ac38c 100644
--- a/activemodel/lib/active_model/type/date.rb
+++ b/activemodel/lib/active_model/type/date.rb
@@ -7,6 +7,10 @@ module ActiveModel
         :date
       end
 
+      def serialize(value)
+        cast(value)
+      end
+
       def type_cast_for_schema(value)
         "'#{value.to_s(:db)}'"
       end
diff --git a/activerecord/test/cases/invalid_date_test.rb b/activerecord/test/cases/date_test.rb
index 426a350379..f112081c14 100644
--- a/activerecord/test/cases/invalid_date_test.rb
+++ b/activerecord/test/cases/date_test.rb
@@ -1,7 +1,19 @@
 require 'cases/helper'
 require 'models/topic'
 
-class InvalidDateTest < ActiveRecord::TestCase
+class DateTest < ActiveRecord::TestCase
+  def test_date_with_time_value
+    time_value = Time.new(2016, 05, 11, 19, 0, 0)
+    topic = Topic.create(last_read: time_value)
+    assert_equal topic, Topic.find_by(last_read: time_value)
+  end
+
+  def test_date_with_string_value
+    string_value = '2016-05-11 19:00:00'
+    topic = Topic.create(last_read: string_value)
+    assert_equal topic, Topic.find_by(last_read: string_value)
+  end
+
   def test_assign_valid_dates
     valid_dates = [[2007, 11, 30], [1993, 2, 28], [2008, 2, 29]]