Merge pull request #17680 from larskanis/fix_bytea_change_detection

PostgreSQL, Fix change detection caused by superfluous bytea unescaping

activerecord/lib/active_record/connection_adapters/postgresql/oid/bytea.rb

@@ -5,6 +5,7 @@ module ActiveRecord
         class Bytea < Type::Binary # :nodoc:
           def type_cast_from_database(value)
             return if value.nil?
+            return value.to_s if value.is_a?(Type::Binary::Data)
             PGconn.unescape_bytea(super)
           end
         end

activerecord/test/cases/dirty_test.rb

@@ -688,7 +688,14 @@ class DirtyTest < ActiveRecord::TestCase
       serialize :data
     end
 
-    klass.create!(data: "foo")
+    binary = klass.create!(data: "\\\\foo")
+
+    assert_not binary.changed?
+
+    binary.data = binary.data.dup
+
+    assert_not binary.changed?
+
     binary = klass.last
 
     assert_not binary.changed?