5 files changed, 22 insertions, 8 deletions
diff --git a/activemodel/lib/active_model/type/time.rb b/activemodel/lib/active_model/type/time.rb
index 16d3efb728..61847a4ce7 100644
--- a/activemodel/lib/active_model/type/time.rb
+++ b/activemodel/lib/active_model/type/time.rb
@@ -13,10 +13,6 @@ module ActiveModel
         :time
       end
 
-      def serialize(value)
-        super || value
-      end
-
       def user_input_in_time_zone(value)
         return unless value.present?
 
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 8d8aa89368..c1ce01c312 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,9 @@
+*   Don't allow `where` with invalid value matches to nil values.
+
+    Fixes #33624.
+
+    *Ryuta Kamizono*
+
 *   SQLite3: Implement `add_foreign_key` and `remove_foreign_key`.
 
     *Ryuta Kamizono*
diff --git a/activerecord/lib/active_record/relation/query_attribute.rb b/activerecord/lib/active_record/relation/query_attribute.rb
index 1dd6462d8d..cd18f27330 100644
--- a/activerecord/lib/active_record/relation/query_attribute.rb
+++ b/activerecord/lib/active_record/relation/query_attribute.rb
@@ -18,8 +18,10 @@ module ActiveRecord
       end
 
       def nil?
-        !value_before_type_cast.is_a?(StatementCache::Substitute) &&
-          (value_before_type_cast.nil? || value_for_database.nil?)
+        unless value_before_type_cast.is_a?(StatementCache::Substitute)
+          value_before_type_cast.nil? ||
+            type.respond_to?(:subtype, true) && value_for_database.nil?
+        end
       rescue ::RangeError
       end
 
diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index 9912763c1b..6591d50d06 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -114,6 +114,12 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
     assert_equal "foobar", uuid.guid_before_type_cast
   end
 
+  def test_invalid_uuid_dont_match_to_nil
+    UUIDType.create!
+    assert_empty UUIDType.where(guid: "")
+    assert_empty UUIDType.where(guid: "foobar")
+  end
+
   def test_acceptable_uuid_regex
     # Valid uuids
     ["A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11",
diff --git a/activerecord/test/cases/relation/where_test.rb b/activerecord/test/cases/relation/where_test.rb
index d49ed092b2..bec204643b 100644
--- a/activerecord/test/cases/relation/where_test.rb
+++ b/activerecord/test/cases/relation/where_test.rb
@@ -50,8 +50,12 @@ module ActiveRecord
       assert_equal [chef], chefs.to_a
     end
 
-    def test_where_with_casted_value_is_nil
-      assert_equal 4, Topic.where(last_read: "").count
+    def test_where_with_invalid_value
+      topics(:first).update!(written_on: nil, bonus_time: nil, last_read: nil)
+      assert_empty Topic.where(parent_id: Object.new)
+      assert_empty Topic.where(written_on: "")
+      assert_empty Topic.where(bonus_time: "")
+      assert_empty Topic.where(last_read: "")
     end
 
     def test_rewhere_on_root