Enforce frozen string in Rubocop

author: Kir Shatrov <shatrov@me.com> 2017-06-22 22:59:18 -0400
committer: Kir Shatrov <shatrov@me.com> 2017-07-01 02:11:03 +0300
commit: cfade1ec7ee7b5b51f3c1578e3474f9c156f2971 (patch)
tree: 5c12d112bf4d039587d712b0cae92a2d920fee23 /activerecord/test
parent: 5fe2a4f929fff7fa725545c47ac0f9372d8c643d (diff)
download: rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.tar.gz
rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.tar.bz2
rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.zip
432 files changed, 444 insertions, 12 deletions
diff --git a/activerecord/test/active_record/connection_adapters/fake_adapter.rb b/activerecord/test/active_record/connection_adapters/fake_adapter.rb
index b0d8050721..9391569f2f 100644
--- a/activerecord/test/active_record/connection_adapters/fake_adapter.rb
+++ b/activerecord/test/active_record/connection_adapters/fake_adapter.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveRecord
   module ConnectionHandling
     def fake_connection(config)
diff --git a/activerecord/test/cases/adapter_test.rb b/activerecord/test/cases/adapter_test.rb
index a1fb6427f9..dd891cb2ed 100644
--- a/activerecord/test/cases/adapter_test.rb
+++ b/activerecord/test/cases/adapter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/book"
 require "models/post"
diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index 67e1efde27..fdf83aaf88 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
index 8f7c803a21..9f3d1459f7 100644
--- a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/adapters/mysql2/boolean_test.rb b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
index 58698d59db..9267d15def 100644
--- a/activerecord/test/cases/adapters/mysql2/boolean_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
index 50ba9ab831..65dc369213 100644
--- a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
index e4a6ed5482..e77f4a90d4 100644
--- a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/connection_test.rb b/activerecord/test/cases/adapters/mysql2/connection_test.rb
index a2faf43b0d..c5ff145e74 100644
--- a/activerecord/test/cases/adapters/mysql2/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/connection_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
index c131a5169c..86e72c149c 100644
--- a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mysql2DatetimePrecisionQuotingTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/enum_test.rb b/activerecord/test/cases/adapters/mysql2/enum_test.rb
index 7ad3e3ca2d..b811179c1b 100644
--- a/activerecord/test/cases/adapters/mysql2/enum_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/enum_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mysql2EnumTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/explain_test.rb b/activerecord/test/cases/adapters/mysql2/explain_test.rb
index 7916921e5a..84c15af08d 100644
--- a/activerecord/test/cases/adapters/mysql2/explain_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/explain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/adapters/mysql2/json_test.rb b/activerecord/test/cases/adapters/mysql2/json_test.rb
index 26c69edc7b..2d39db4ce2 100644
--- a/activerecord/test/cases/adapters/mysql2/json_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/json_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "cases/json_shared_test_cases"
 
diff --git a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
index 565130c38f..7ba388bee1 100644
--- a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/ddl_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
index 251a50e41e..4a421e2b91 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/schema_test.rb b/activerecord/test/cases/adapters/mysql2/schema_test.rb
index 1fad5585de..c4bf58c13e 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/adapters/mysql2/sp_test.rb b/activerecord/test/cases/adapters/mysql2/sp_test.rb
index 4182532535..d4c4d02f79 100644
--- a/activerecord/test/cases/adapters/mysql2/sp_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sp_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
index d6e7f29a5c..c412166451 100644
--- a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mysql2SqlTypesTest < ActiveRecord::Mysql2TestCase
diff --git a/activerecord/test/cases/adapters/mysql2/table_options_test.rb b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
index 61a8ce9bc0..54da2195d1 100644
--- a/activerecord/test/cases/adapters/mysql2/table_options_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
index 16101e38cb..e447e6ec83 100644
--- a/activerecord/test/cases/adapters/mysql2/transaction_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
index 71dcfaa241..1703e8fef7 100644
--- a/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/unsigned_type_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb b/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb
index 442a4fb7b5..85e283bfe1 100644
--- a/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/virtual_column_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
index b787de8453..441e84a117 100644
--- a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/array_test.rb b/activerecord/test/cases/adapters/postgresql/array_test.rb
index 121c62dadf..a642145726 100644
--- a/activerecord/test/cases/adapters/postgresql/array_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/array_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
index 7712e809a2..d7ed0aa8dd 100644
--- a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 require "support/schema_dumping_helper"
diff --git a/activerecord/test/cases/adapters/postgresql/bytea_test.rb b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
index 539c90f0bc..7cb5c2442c 100644
--- a/activerecord/test/cases/adapters/postgresql/bytea_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb b/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb
index 03b44feab6..b6db6e5e28 100644
--- a/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/case_insensitive_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlCaseInsensitiveTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
index ea642069d2..9d7fddfc02 100644
--- a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/adapters/postgresql/cidr_test.rb b/activerecord/test/cases/adapters/postgresql/cidr_test.rb
index 52f2a0096c..fccd8b3c7b 100644
--- a/activerecord/test/cases/adapters/postgresql/cidr_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/cidr_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "ipaddr"
 
diff --git a/activerecord/test/cases/adapters/postgresql/citext_test.rb b/activerecord/test/cases/adapters/postgresql/citext_test.rb
index ca95e4b626..ffdd2983c6 100644
--- a/activerecord/test/cases/adapters/postgresql/citext_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/citext_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/collation_test.rb b/activerecord/test/cases/adapters/postgresql/collation_test.rb
index a603221d8f..2929c9ad94 100644
--- a/activerecord/test/cases/adapters/postgresql/collation_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/collation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/composite_test.rb b/activerecord/test/cases/adapters/postgresql/composite_test.rb
index 1da2a9e2ac..9eb422a8a3 100644
--- a/activerecord/test/cases/adapters/postgresql/composite_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/composite_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/connection_test.rb b/activerecord/test/cases/adapters/postgresql/connection_test.rb
index 32afe331fa..3adae7e146 100644
--- a/activerecord/test/cases/adapters/postgresql/connection_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/connection_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/datatype_test.rb b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
index 0725fde5ae..f947868898 100644
--- a/activerecord/test/cases/adapters/postgresql/datatype_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/ddl_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/domain_test.rb b/activerecord/test/cases/adapters/postgresql/domain_test.rb
index f1eb8adb15..b16e0f9265 100644
--- a/activerecord/test/cases/adapters/postgresql/domain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/domain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/enum_test.rb b/activerecord/test/cases/adapters/postgresql/enum_test.rb
index 5e5a3158ba..0f8ab8ab23 100644
--- a/activerecord/test/cases/adapters/postgresql/enum_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/enum_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/explain_test.rb b/activerecord/test/cases/adapters/postgresql/explain_test.rb
index d79fbccf47..8a0cf440fd 100644
--- a/activerecord/test/cases/adapters/postgresql/explain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/explain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb b/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
index b56c226763..ba2b4e1fbf 100644
--- a/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/extension_migration_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlExtensionMigrationTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/full_text_test.rb b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
index 5ddfe32007..fa8aadd224 100644
--- a/activerecord/test/cases/adapters/postgresql/full_text_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/geometric_test.rb b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
index 3b6840a1c9..34836b2421 100644
--- a/activerecord/test/cases/adapters/postgresql/geometric_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 require "support/schema_dumping_helper"
diff --git a/activerecord/test/cases/adapters/postgresql/hstore_test.rb b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
index f9cce10fb8..b547868b57 100644
--- a/activerecord/test/cases/adapters/postgresql/hstore_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/infinity_test.rb b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
index b9e177e6ec..df5c688881 100644
--- a/activerecord/test/cases/adapters/postgresql/infinity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/integer_test.rb b/activerecord/test/cases/adapters/postgresql/integer_test.rb
index b4e55964b9..5557e869ad 100644
--- a/activerecord/test/cases/adapters/postgresql/integer_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/integer_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_support/core_ext/numeric/bytes"
 
diff --git a/activerecord/test/cases/adapters/postgresql/json_test.rb b/activerecord/test/cases/adapters/postgresql/json_test.rb
index 6aa60630c2..4438f349cc 100644
--- a/activerecord/test/cases/adapters/postgresql/json_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/json_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "cases/json_shared_test_cases"
 
diff --git a/activerecord/test/cases/adapters/postgresql/ltree_test.rb b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
index 2b5ac1cac6..447d68316c 100644
--- a/activerecord/test/cases/adapters/postgresql/ltree_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/money_test.rb b/activerecord/test/cases/adapters/postgresql/money_test.rb
index 1b5d8362af..530aeb0c29 100644
--- a/activerecord/test/cases/adapters/postgresql/money_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/money_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/network_test.rb b/activerecord/test/cases/adapters/postgresql/network_test.rb
index a33b0ef8a7..2bbfb292c4 100644
--- a/activerecord/test/cases/adapters/postgresql/network_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/network_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/numbers_test.rb b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
index bfb2b7c27a..82edf7db3f 100644
--- a/activerecord/test/cases/adapters/postgresql/numbers_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlNumberTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 76e0ad60fe..7c7bb0a942 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/ddl_helper"
 require "support/connection_helper"
diff --git a/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb b/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb
index 8c62690866..0120e33f70 100644
--- a/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/prepared_statements_disabled_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/computer"
 require "models/developer"
diff --git a/activerecord/test/cases/adapters/postgresql/quoting_test.rb b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
index a1e966b915..1205559558 100644
--- a/activerecord/test/cases/adapters/postgresql/quoting_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/adapters/postgresql/range_test.rb b/activerecord/test/cases/adapters/postgresql/range_test.rb
index f411884dfd..8de162a8a1 100644
--- a/activerecord/test/cases/adapters/postgresql/range_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/range_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
index 0ff04bfa27..0b17c141c8 100644
--- a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/rename_table_test.rb b/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
index e9e7f717ac..5b253999d5 100644
--- a/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/rename_table_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlRenameTableTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
index f86a76e08a..db7d8ba751 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class SchemaThing < ActiveRecord::Base
diff --git a/activerecord/test/cases/adapters/postgresql/schema_test.rb b/activerecord/test/cases/adapters/postgresql/schema_test.rb
index f6b957476b..5438665d42 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/default"
 require "support/schema_dumping_helper"
diff --git a/activerecord/test/cases/adapters/postgresql/serial_test.rb b/activerecord/test/cases/adapters/postgresql/serial_test.rb
index d711b3b729..4930d3f67a 100644
--- a/activerecord/test/cases/adapters/postgresql/serial_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/serial_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
index 146b619a4b..73cf91425b 100644
--- a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
index 962450aada..c7dec25f3a 100644
--- a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/topic"
diff --git a/activerecord/test/cases/adapters/postgresql/transaction_test.rb b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
index 9b42d0383d..c1b19c11f5 100644
--- a/activerecord/test/cases/adapters/postgresql/transaction_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 require "concurrent/atomic/cyclic_barrier"
diff --git a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
index 784d77a8d1..688117722b 100644
--- a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class PostgresqlTypeLookupTest < ActiveRecord::PostgreSQLTestCase
diff --git a/activerecord/test/cases/adapters/postgresql/utils_test.rb b/activerecord/test/cases/adapters/postgresql/utils_test.rb
index 9f9e3bda2f..1a655d7843 100644
--- a/activerecord/test/cases/adapters/postgresql/utils_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/utils_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/connection_adapters/postgresql/utils"
 
diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index 8eddd81c38..49c570c917 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/postgresql/xml_test.rb b/activerecord/test/cases/adapters/postgresql/xml_test.rb
index 826b384fb3..b0720b5a6e 100644
--- a/activerecord/test/cases/adapters/postgresql/xml_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/xml_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/sqlite3/collation_test.rb b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
index dd88ed3656..f3cbb408f1 100644
--- a/activerecord/test/cases/adapters/sqlite3/collation_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
index e1cfd703e8..cc1f74ed41 100644
--- a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class CopyTableTest < ActiveRecord::SQLite3TestCase
diff --git a/activerecord/test/cases/adapters/sqlite3/explain_test.rb b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
index 29d97ae78c..a3f6299756 100644
--- a/activerecord/test/cases/adapters/sqlite3/explain_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
index aefbb309e6..0a5bf7754c 100644
--- a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "bigdecimal"
 require "securerandom"
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index 9a812e325e..7adba54836 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/owner"
 require "tempfile"
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
index b1b4463bf1..d23a7ac532 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/owner"
 
diff --git a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
index 37ff973397..76841c235a 100644
--- a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class SQLite3StatementPoolTest < ActiveRecord::SQLite3TestCase
diff --git a/activerecord/test/cases/aggregations_test.rb b/activerecord/test/cases/aggregations_test.rb
index f8136fde72..97be9c447a 100644
--- a/activerecord/test/cases/aggregations_test.rb
+++ b/activerecord/test/cases/aggregations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/customer"
 
diff --git a/activerecord/test/cases/ar_schema_test.rb b/activerecord/test/cases/ar_schema_test.rb
index 5b608d8e83..aaae3736a9 100644
--- a/activerecord/test/cases/ar_schema_test.rb
+++ b/activerecord/test/cases/ar_schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class ActiveRecordSchemaTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/associations/association_scope_test.rb b/activerecord/test/cases/associations/association_scope_test.rb
index c54542ff7b..a57eb78a14 100644
--- a/activerecord/test/cases/associations/association_scope_test.rb
+++ b/activerecord/test/cases/associations/association_scope_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/author"
diff --git a/activerecord/test/cases/associations/belongs_to_associations_test.rb b/activerecord/test/cases/associations/belongs_to_associations_test.rb
index a727cc6e60..af3f40974d 100644
--- a/activerecord/test/cases/associations/belongs_to_associations_test.rb
+++ b/activerecord/test/cases/associations/belongs_to_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/project"
diff --git a/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb b/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
index 8a0e041864..eee327a0bc 100644
--- a/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
+++ b/activerecord/test/cases/associations/bidirectional_destroy_dependencies_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/content"
 
diff --git a/activerecord/test/cases/associations/callbacks_test.rb b/activerecord/test/cases/associations/callbacks_test.rb
index f9d1e44595..b91fb5b7ed 100644
--- a/activerecord/test/cases/associations/callbacks_test.rb
+++ b/activerecord/test/cases/associations/callbacks_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/author"
diff --git a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
index 7b0445025c..ea2582b507 100644
--- a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
+++ b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb b/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
index 61f39b4136..f6de62b1af 100644
--- a/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
+++ b/activerecord/test/cases/associations/eager_load_includes_full_sti_class_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/tagging"
diff --git a/activerecord/test/cases/associations/eager_load_nested_include_test.rb b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
index e9f551b6b2..83c85cd022 100644
--- a/activerecord/test/cases/associations/eager_load_nested_include_test.rb
+++ b/activerecord/test/cases/associations/eager_load_nested_include_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/tag"
diff --git a/activerecord/test/cases/associations/eager_singularization_test.rb b/activerecord/test/cases/associations/eager_singularization_test.rb
index 16eff15026..860bb9ac54 100644
--- a/activerecord/test/cases/associations/eager_singularization_test.rb
+++ b/activerecord/test/cases/associations/eager_singularization_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class EagerSingularizationTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 55b294cfaa..e0b137304b 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/tagging"
diff --git a/activerecord/test/cases/associations/extension_test.rb b/activerecord/test/cases/associations/extension_test.rb
index f707a170f5..d2f21583a7 100644
--- a/activerecord/test/cases/associations/extension_test.rb
+++ b/activerecord/test/cases/associations/extension_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index f73005b3cb..fa40bd2ff8 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index a936017ae3..07354a2379 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/associations/has_many_through_associations_test.rb b/activerecord/test/cases/associations/has_many_through_associations_test.rb
index 1c2138a3d0..6794428688 100644
--- a/activerecord/test/cases/associations/has_many_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_through_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/person"
diff --git a/activerecord/test/cases/associations/has_one_associations_test.rb b/activerecord/test/cases/associations/has_one_associations_test.rb
index bf3b8dcd63..545eec7e5d 100644
--- a/activerecord/test/cases/associations/has_one_associations_test.rb
+++ b/activerecord/test/cases/associations/has_one_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/associations/has_one_through_associations_test.rb b/activerecord/test/cases/associations/has_one_through_associations_test.rb
index 28b883586d..0a74a9e710 100644
--- a/activerecord/test/cases/associations/has_one_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_one_through_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/club"
 require "models/member_type"
diff --git a/activerecord/test/cases/associations/inner_join_association_test.rb b/activerecord/test/cases/associations/inner_join_association_test.rb
index ddf5bc6f0b..6fff4171c8 100644
--- a/activerecord/test/cases/associations/inner_join_association_test.rb
+++ b/activerecord/test/cases/associations/inner_join_association_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/associations/inverse_associations_test.rb b/activerecord/test/cases/associations/inverse_associations_test.rb
index 467cc73ecd..d8f7d3b21c 100644
--- a/activerecord/test/cases/associations/inverse_associations_test.rb
+++ b/activerecord/test/cases/associations/inverse_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/man"
 require "models/face"
diff --git a/activerecord/test/cases/associations/join_model_test.rb b/activerecord/test/cases/associations/join_model_test.rb
index c078cef064..c2758b30a1 100644
--- a/activerecord/test/cases/associations/join_model_test.rb
+++ b/activerecord/test/cases/associations/join_model_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/tag"
 require "models/tagging"
diff --git a/activerecord/test/cases/associations/left_outer_join_association_test.rb b/activerecord/test/cases/associations/left_outer_join_association_test.rb
index 6d3757f467..68c9286972 100644
--- a/activerecord/test/cases/associations/left_outer_join_association_test.rb
+++ b/activerecord/test/cases/associations/left_outer_join_association_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/associations/nested_through_associations_test.rb b/activerecord/test/cases/associations/nested_through_associations_test.rb
index 67ff7355b3..90b2d4bc07 100644
--- a/activerecord/test/cases/associations/nested_through_associations_test.rb
+++ b/activerecord/test/cases/associations/nested_through_associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/post"
diff --git a/activerecord/test/cases/associations/required_test.rb b/activerecord/test/cases/associations/required_test.rb
index 45e1803858..6cf2d8ac12 100644
--- a/activerecord/test/cases/associations/required_test.rb
+++ b/activerecord/test/cases/associations/required_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class RequiredAssociationsTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/associations_test.rb b/activerecord/test/cases/associations_test.rb
index 2eb31326a5..ba2f4c11c8 100644
--- a/activerecord/test/cases/associations_test.rb
+++ b/activerecord/test/cases/associations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/computer"
 require "models/developer"
diff --git a/activerecord/test/cases/attribute_decorators_test.rb b/activerecord/test/cases/attribute_decorators_test.rb
index cfa6ed1da6..eb8efab6a5 100644
--- a/activerecord/test/cases/attribute_decorators_test.rb
+++ b/activerecord/test/cases/attribute_decorators_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/attribute_methods/read_test.rb b/activerecord/test/cases/attribute_methods/read_test.rb
index 1fc63a49d4..a366144e17 100644
--- a/activerecord/test/cases/attribute_methods/read_test.rb
+++ b/activerecord/test/cases/attribute_methods/read_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index 4d24a980dc..1f3a3652d7 100644
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/minimalistic"
 require "models/developer"
diff --git a/activerecord/test/cases/attribute_set_test.rb b/activerecord/test/cases/attribute_set_test.rb
index bd4b200735..80c67f171b 100644
--- a/activerecord/test/cases/attribute_set_test.rb
+++ b/activerecord/test/cases/attribute_set_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/attribute_test.rb b/activerecord/test/cases/attribute_test.rb
index 7cf6b498c9..0271ed5fb9 100644
--- a/activerecord/test/cases/attribute_test.rb
+++ b/activerecord/test/cases/attribute_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/attributes_test.rb b/activerecord/test/cases/attributes_test.rb
index 3705a6be89..8aa515fe6e 100644
--- a/activerecord/test/cases/attributes_test.rb
+++ b/activerecord/test/cases/attributes_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class OverloadedType < ActiveRecord::Base
diff --git a/activerecord/test/cases/autosave_association_test.rb b/activerecord/test/cases/autosave_association_test.rb
index 2203aa1788..db2a19ea62 100644
--- a/activerecord/test/cases/autosave_association_test.rb
+++ b/activerecord/test/cases/autosave_association_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/bird"
 require "models/post"
diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index dc32e995a4..a26a4bbb61 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/author"
diff --git a/activerecord/test/cases/batches_test.rb b/activerecord/test/cases/batches_test.rb
index fbc3fbb44f..1f666a5d39 100644
--- a/activerecord/test/cases/batches_test.rb
+++ b/activerecord/test/cases/batches_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/subscriber"
diff --git a/activerecord/test/cases/binary_test.rb b/activerecord/test/cases/binary_test.rb
index 1fc30e24d2..324a74492c 100644
--- a/activerecord/test/cases/binary_test.rb
+++ b/activerecord/test/cases/binary_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 # Without using prepared statements, it makes no sense to test
diff --git a/activerecord/test/cases/bind_parameter_test.rb b/activerecord/test/cases/bind_parameter_test.rb
index 5af44c27eb..8504f586cc 100644
--- a/activerecord/test/cases/bind_parameter_test.rb
+++ b/activerecord/test/cases/bind_parameter_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/author"
diff --git a/activerecord/test/cases/cache_key_test.rb b/activerecord/test/cases/cache_key_test.rb
index 7b8264e6e8..f0a1bb9e22 100644
--- a/activerecord/test/cases/cache_key_test.rb
+++ b/activerecord/test/cases/cache_key_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/calculations_test.rb b/activerecord/test/cases/calculations_test.rb
index 80baaac30a..478b9fe742 100644
--- a/activerecord/test/cases/calculations_test.rb
+++ b/activerecord/test/cases/calculations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/book"
 require "models/club"
diff --git a/activerecord/test/cases/callbacks_test.rb b/activerecord/test/cases/callbacks_test.rb
index b3c86586d0..55deaa6947 100644
--- a/activerecord/test/cases/callbacks_test.rb
+++ b/activerecord/test/cases/callbacks_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/developer"
 require "models/computer"
diff --git a/activerecord/test/cases/clone_test.rb b/activerecord/test/cases/clone_test.rb
index b89294c094..fa0f53676e 100644
--- a/activerecord/test/cases/clone_test.rb
+++ b/activerecord/test/cases/clone_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/coders/json_test.rb b/activerecord/test/cases/coders/json_test.rb
index d22d93d129..95e6fb3e7b 100644
--- a/activerecord/test/cases/coders/json_test.rb
+++ b/activerecord/test/cases/coders/json_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/coders/yaml_column_test.rb b/activerecord/test/cases/coders/yaml_column_test.rb
index a26a72712d..e3e85a58a4 100644
--- a/activerecord/test/cases/coders/yaml_column_test.rb
+++ b/activerecord/test/cases/coders/yaml_column_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/collection_cache_key_test.rb b/activerecord/test/cases/collection_cache_key_test.rb
index f344c77691..2d10a68416 100644
--- a/activerecord/test/cases/collection_cache_key_test.rb
+++ b/activerecord/test/cases/collection_cache_key_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/computer"
 require "models/developer"
diff --git a/activerecord/test/cases/column_alias_test.rb b/activerecord/test/cases/column_alias_test.rb
index 9893ba9580..506ae05756 100644
--- a/activerecord/test/cases/column_alias_test.rb
+++ b/activerecord/test/cases/column_alias_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/column_definition_test.rb b/activerecord/test/cases/column_definition_test.rb
index 90c8d21c43..fcb0952c1c 100644
--- a/activerecord/test/cases/column_definition_test.rb
+++ b/activerecord/test/cases/column_definition_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/comment_test.rb b/activerecord/test/cases/comment_test.rb
index c23be52a6c..5c91ac347c 100644
--- a/activerecord/test/cases/comment_test.rb
+++ b/activerecord/test/cases/comment_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
index 64189381cb..4f88b129af 100644
--- a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
+++ b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/connection_adapters/connection_handler_test.rb b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
index 2a71f08d90..f8725ddb01 100644
--- a/activerecord/test/cases/connection_adapters/connection_handler_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/connection_adapters/connection_specification_test.rb b/activerecord/test/cases/connection_adapters/connection_specification_test.rb
index 10a3521c79..40998c06bf 100644
--- a/activerecord/test/cases/connection_adapters/connection_specification_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_specification_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb b/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
index 8faa67255d..7c98c80e39 100644
--- a/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
+++ b/activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb b/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
index 3657b8340d..133632bac9 100644
--- a/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
+++ b/activerecord/test/cases/connection_adapters/mysql_type_lookup_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 if current_adapter?(:Mysql2Adapter)
diff --git a/activerecord/test/cases/connection_adapters/schema_cache_test.rb b/activerecord/test/cases/connection_adapters/schema_cache_test.rb
index 106323ccc9..3370818616 100644
--- a/activerecord/test/cases/connection_adapters/schema_cache_test.rb
+++ b/activerecord/test/cases/connection_adapters/schema_cache_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/connection_adapters/type_lookup_test.rb b/activerecord/test/cases/connection_adapters/type_lookup_test.rb
index a348c2d783..251483da44 100644
--- a/activerecord/test/cases/connection_adapters/type_lookup_test.rb
+++ b/activerecord/test/cases/connection_adapters/type_lookup_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 unless current_adapter?(:PostgreSQLAdapter) # PostgreSQL does not use type strings for lookup
diff --git a/activerecord/test/cases/connection_management_test.rb b/activerecord/test/cases/connection_management_test.rb
index d1e946d401..9bd0aab981 100644
--- a/activerecord/test/cases/connection_management_test.rb
+++ b/activerecord/test/cases/connection_management_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "rack"
 
diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb
index 00a0187b57..adbd158e7a 100644
--- a/activerecord/test/cases/connection_pool_test.rb
+++ b/activerecord/test/cases/connection_pool_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "concurrent/atomic/count_down_latch"
 
diff --git a/activerecord/test/cases/connection_specification/resolver_test.rb b/activerecord/test/cases/connection_specification/resolver_test.rb
index 13b5bae13c..3d97281627 100644
--- a/activerecord/test/cases/connection_specification/resolver_test.rb
+++ b/activerecord/test/cases/connection_specification/resolver_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/core_test.rb b/activerecord/test/cases/core_test.rb
index 3735572898..0345608191 100644
--- a/activerecord/test/cases/core_test.rb
+++ b/activerecord/test/cases/core_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/person"
 require "models/topic"
diff --git a/activerecord/test/cases/counter_cache_test.rb b/activerecord/test/cases/counter_cache_test.rb
index 46d7526cc0..14800e6b91 100644
--- a/activerecord/test/cases/counter_cache_test.rb
+++ b/activerecord/test/cases/counter_cache_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/car"
diff --git a/activerecord/test/cases/custom_locking_test.rb b/activerecord/test/cases/custom_locking_test.rb
index 15c8b684e4..e170843952 100644
--- a/activerecord/test/cases/custom_locking_test.rb
+++ b/activerecord/test/cases/custom_locking_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/person"
 
diff --git a/activerecord/test/cases/database_statements_test.rb b/activerecord/test/cases/database_statements_test.rb
index 66035865be..5df028d397 100644
--- a/activerecord/test/cases/database_statements_test.rb
+++ b/activerecord/test/cases/database_statements_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class DatabaseStatementsTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/date_test.rb b/activerecord/test/cases/date_test.rb
index 2edc0415cd..202100ff69 100644
--- a/activerecord/test/cases/date_test.rb
+++ b/activerecord/test/cases/date_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/date_time_precision_test.rb b/activerecord/test/cases/date_time_precision_test.rb
index e4a2f9ee17..12b1858991 100644
--- a/activerecord/test/cases/date_time_precision_test.rb
+++ b/activerecord/test/cases/date_time_precision_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/date_time_test.rb b/activerecord/test/cases/date_time_test.rb
index ad7da9de70..8753c95641 100644
--- a/activerecord/test/cases/date_time_test.rb
+++ b/activerecord/test/cases/date_time_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/task"
diff --git a/activerecord/test/cases/defaults_test.rb b/activerecord/test/cases/defaults_test.rb
index 996d298689..30cfa0744f 100644
--- a/activerecord/test/cases/defaults_test.rb
+++ b/activerecord/test/cases/defaults_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 require "models/default"
diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb
index f72e0d2ead..cc2724502b 100644
--- a/activerecord/test/cases/dirty_test.rb
+++ b/activerecord/test/cases/dirty_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"    # For booleans
 require "models/pirate"   # For timestamps
diff --git a/activerecord/test/cases/disconnected_test.rb b/activerecord/test/cases/disconnected_test.rb
index c25089a420..92365351b1 100644
--- a/activerecord/test/cases/disconnected_test.rb
+++ b/activerecord/test/cases/disconnected_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class TestRecord < ActiveRecord::Base
diff --git a/activerecord/test/cases/dup_test.rb b/activerecord/test/cases/dup_test.rb
index 000ed27efb..76979dc798 100644
--- a/activerecord/test/cases/dup_test.rb
+++ b/activerecord/test/cases/dup_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/reply"
 require "models/topic"
diff --git a/activerecord/test/cases/enum_test.rb b/activerecord/test/cases/enum_test.rb
index 4ef9a125e6..8e13582f3e 100644
--- a/activerecord/test/cases/enum_test.rb
+++ b/activerecord/test/cases/enum_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/book"
diff --git a/activerecord/test/cases/errors_test.rb b/activerecord/test/cases/errors_test.rb
index e90669e0c7..45e28c4f03 100644
--- a/activerecord/test/cases/errors_test.rb
+++ b/activerecord/test/cases/errors_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class ErrorsTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/explain_subscriber_test.rb b/activerecord/test/cases/explain_subscriber_test.rb
index ca87e04012..0fb6bf2eed 100644
--- a/activerecord/test/cases/explain_subscriber_test.rb
+++ b/activerecord/test/cases/explain_subscriber_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/explain_subscriber"
 require "active_record/explain_registry"
diff --git a/activerecord/test/cases/explain_test.rb b/activerecord/test/cases/explain_test.rb
index 4f6bd9327c..de3ec36667 100644
--- a/activerecord/test/cases/explain_test.rb
+++ b/activerecord/test/cases/explain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/car"
 require "active_support/core_ext/string/strip"
diff --git a/activerecord/test/cases/finder_respond_to_test.rb b/activerecord/test/cases/finder_respond_to_test.rb
index 3eaa993d45..29d7dee343 100644
--- a/activerecord/test/cases/finder_respond_to_test.rb
+++ b/activerecord/test/cases/finder_respond_to_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 420f552ef6..752ac519a4 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/author"
diff --git a/activerecord/test/cases/fixture_set/file_test.rb b/activerecord/test/cases/fixture_set/file_test.rb
index 533edcc2e0..c7058133b2 100644
--- a/activerecord/test/cases/fixture_set/file_test.rb
+++ b/activerecord/test/cases/fixture_set/file_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "tempfile"
 
diff --git a/activerecord/test/cases/fixtures_test.rb b/activerecord/test/cases/fixtures_test.rb
index b499e60922..91d0908450 100644
--- a/activerecord/test/cases/fixtures_test.rb
+++ b/activerecord/test/cases/fixtures_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/admin"
 require "models/admin/account"
diff --git a/activerecord/test/cases/forbidden_attributes_protection_test.rb b/activerecord/test/cases/forbidden_attributes_protection_test.rb
index ffa3f63e0d..d11ec08dea 100644
--- a/activerecord/test/cases/forbidden_attributes_protection_test.rb
+++ b/activerecord/test/cases/forbidden_attributes_protection_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_support/core_ext/hash/indifferent_access"
 
diff --git a/activerecord/test/cases/habtm_destroy_order_test.rb b/activerecord/test/cases/habtm_destroy_order_test.rb
index 365d4576dd..124e3216d0 100644
--- a/activerecord/test/cases/habtm_destroy_order_test.rb
+++ b/activerecord/test/cases/habtm_destroy_order_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/lesson"
 require "models/student"
diff --git a/activerecord/test/cases/helper.rb b/activerecord/test/cases/helper.rb
index 5a3b8e3fb5..84a784e6d5 100644
--- a/activerecord/test/cases/helper.rb
+++ b/activerecord/test/cases/helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "config"
 
 require "stringio"
diff --git a/activerecord/test/cases/hot_compatibility_test.rb b/activerecord/test/cases/hot_compatibility_test.rb
index e107ff2362..970ccc3601 100644
--- a/activerecord/test/cases/hot_compatibility_test.rb
+++ b/activerecord/test/cases/hot_compatibility_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/connection_helper"
 
diff --git a/activerecord/test/cases/i18n_test.rb b/activerecord/test/cases/i18n_test.rb
index 7f03c5b23d..94b5e4ef2f 100644
--- a/activerecord/test/cases/i18n_test.rb
+++ b/activerecord/test/cases/i18n_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/inheritance_test.rb b/activerecord/test/cases/inheritance_test.rb
index fb5a7bcc31..e73d9d0a27 100644
--- a/activerecord/test/cases/inheritance_test.rb
+++ b/activerecord/test/cases/inheritance_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/company"
diff --git a/activerecord/test/cases/integration_test.rb b/activerecord/test/cases/integration_test.rb
index 9104976126..1075366fb1 100644
--- a/activerecord/test/cases/integration_test.rb
+++ b/activerecord/test/cases/integration_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/company"
 require "models/developer"
diff --git a/activerecord/test/cases/invalid_connection_test.rb b/activerecord/test/cases/invalid_connection_test.rb
index 1367af2859..256ad59407 100644
--- a/activerecord/test/cases/invalid_connection_test.rb
+++ b/activerecord/test/cases/invalid_connection_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 if current_adapter?(:Mysql2Adapter)
diff --git a/activerecord/test/cases/invertible_migration_test.rb b/activerecord/test/cases/invertible_migration_test.rb
index cc3951e2ba..a44a351209 100644
--- a/activerecord/test/cases/invertible_migration_test.rb
+++ b/activerecord/test/cases/invertible_migration_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Horse < ActiveRecord::Base
diff --git a/activerecord/test/cases/json_attribute_test.rb b/activerecord/test/cases/json_attribute_test.rb
index e5848b45f8..c64e2c31de 100644
--- a/activerecord/test/cases/json_attribute_test.rb
+++ b/activerecord/test/cases/json_attribute_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "cases/json_shared_test_cases"
 
diff --git a/activerecord/test/cases/json_serialization_test.rb b/activerecord/test/cases/json_serialization_test.rb
index 9b4b61b16e..2ca95fe3b4 100644
--- a/activerecord/test/cases/json_serialization_test.rb
+++ b/activerecord/test/cases/json_serialization_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/contact"
 require "models/post"
diff --git a/activerecord/test/cases/json_shared_test_cases.rb b/activerecord/test/cases/json_shared_test_cases.rb
index 9a1c1c3f3f..1eeefb78dd 100644
--- a/activerecord/test/cases/json_shared_test_cases.rb
+++ b/activerecord/test/cases/json_shared_test_cases.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "support/schema_dumping_helper"
 
 module JSONSharedTestCases
diff --git a/activerecord/test/cases/locking_test.rb b/activerecord/test/cases/locking_test.rb
index 2fc52393f2..e67ec22c42 100644
--- a/activerecord/test/cases/locking_test.rb
+++ b/activerecord/test/cases/locking_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "thread"
 require "cases/helper"
 require "models/person"
diff --git a/activerecord/test/cases/log_subscriber_test.rb b/activerecord/test/cases/log_subscriber_test.rb
index b80257962c..0eaca0d001 100644
--- a/activerecord/test/cases/log_subscriber_test.rb
+++ b/activerecord/test/cases/log_subscriber_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/binary"
 require "models/developer"
diff --git a/activerecord/test/cases/migration/change_schema_test.rb b/activerecord/test/cases/migration/change_schema_test.rb
index 1d305fa11f..e706fc4f08 100644
--- a/activerecord/test/cases/migration/change_schema_test.rb
+++ b/activerecord/test/cases/migration/change_schema_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/change_table_test.rb b/activerecord/test/cases/migration/change_table_test.rb
index ec817a579b..f1ca91887b 100644
--- a/activerecord/test/cases/migration/change_table_test.rb
+++ b/activerecord/test/cases/migration/change_table_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/migration/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/column_attributes_test.rb b/activerecord/test/cases/migration/column_attributes_test.rb
index 48df931543..5ef0847a64 100644
--- a/activerecord/test/cases/migration/column_attributes_test.rb
+++ b/activerecord/test/cases/migration/column_attributes_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/migration/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/column_positioning_test.rb b/activerecord/test/cases/migration/column_positioning_test.rb
index f2162d91b1..bdbad431e8 100644
--- a/activerecord/test/cases/migration/column_positioning_test.rb
+++ b/activerecord/test/cases/migration/column_positioning_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/columns_test.rb b/activerecord/test/cases/migration/columns_test.rb
index 2329888345..c4751277f7 100644
--- a/activerecord/test/cases/migration/columns_test.rb
+++ b/activerecord/test/cases/migration/columns_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/migration/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/command_recorder_test.rb b/activerecord/test/cases/migration/command_recorder_test.rb
index 007926f1b9..be200a7225 100644
--- a/activerecord/test/cases/migration/command_recorder_test.rb
+++ b/activerecord/test/cases/migration/command_recorder_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/compatibility_test.rb b/activerecord/test/cases/migration/compatibility_test.rb
index 596a21dcbc..4321f967d2 100644
--- a/activerecord/test/cases/migration/compatibility_test.rb
+++ b/activerecord/test/cases/migration/compatibility_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/migration/create_join_table_test.rb b/activerecord/test/cases/migration/create_join_table_test.rb
index c4896f3d6e..0e9e880fe1 100644
--- a/activerecord/test/cases/migration/create_join_table_test.rb
+++ b/activerecord/test/cases/migration/create_join_table_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/foreign_key_test.rb b/activerecord/test/cases/migration/foreign_key_test.rb
index 7762d37915..7a44b2db75 100644
--- a/activerecord/test/cases/migration/foreign_key_test.rb
+++ b/activerecord/test/cases/migration/foreign_key_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/migration/helper.rb b/activerecord/test/cases/migration/helper.rb
index 9c0fa7339d..e366ed92b1 100644
--- a/activerecord/test/cases/migration/helper.rb
+++ b/activerecord/test/cases/migration/helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/index_test.rb b/activerecord/test/cases/migration/index_test.rb
index f10fcf1398..ccc0f4948f 100644
--- a/activerecord/test/cases/migration/index_test.rb
+++ b/activerecord/test/cases/migration/index_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/logger_test.rb b/activerecord/test/cases/migration/logger_test.rb
index 3d7c7ad469..9fe64b73a8 100644
--- a/activerecord/test/cases/migration/logger_test.rb
+++ b/activerecord/test/cases/migration/logger_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/pending_migrations_test.rb b/activerecord/test/cases/migration/pending_migrations_test.rb
index 6970fdcc87..0cb4b6cfa1 100644
--- a/activerecord/test/cases/migration/pending_migrations_test.rb
+++ b/activerecord/test/cases/migration/pending_migrations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/references_foreign_key_test.rb b/activerecord/test/cases/migration/references_foreign_key_test.rb
index 718b9a0613..405fd7aaed 100644
--- a/activerecord/test/cases/migration/references_foreign_key_test.rb
+++ b/activerecord/test/cases/migration/references_foreign_key_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 if ActiveRecord::Base.connection.supports_foreign_keys_in_create?
diff --git a/activerecord/test/cases/migration/references_index_test.rb b/activerecord/test/cases/migration/references_index_test.rb
index 2866cabab6..2954f1e275 100644
--- a/activerecord/test/cases/migration/references_index_test.rb
+++ b/activerecord/test/cases/migration/references_index_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/references_statements_test.rb b/activerecord/test/cases/migration/references_statements_test.rb
index e9eb9968cb..f8b373bdee 100644
--- a/activerecord/test/cases/migration/references_statements_test.rb
+++ b/activerecord/test/cases/migration/references_statements_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/migration/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration/rename_table_test.rb b/activerecord/test/cases/migration/rename_table_test.rb
index 5da3ad33a3..bee528ca8a 100644
--- a/activerecord/test/cases/migration/rename_table_test.rb
+++ b/activerecord/test/cases/migration/rename_table_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/migration/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 3a49a41580..315e58668a 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "cases/migration/helper"
 require "bigdecimal/util"
diff --git a/activerecord/test/cases/migrator_test.rb b/activerecord/test/cases/migrator_test.rb
index 2e4b454a86..b93643922d 100644
--- a/activerecord/test/cases/migrator_test.rb
+++ b/activerecord/test/cases/migrator_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "cases/migration/helper"
 
diff --git a/activerecord/test/cases/mixin_test.rb b/activerecord/test/cases/mixin_test.rb
index a8af8e30f7..82190c283e 100644
--- a/activerecord/test/cases/mixin_test.rb
+++ b/activerecord/test/cases/mixin_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class Mixin < ActiveRecord::Base
diff --git a/activerecord/test/cases/modules_test.rb b/activerecord/test/cases/modules_test.rb
index f8a7bab35f..514911cb13 100644
--- a/activerecord/test/cases/modules_test.rb
+++ b/activerecord/test/cases/modules_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/company_in_module"
 require "models/shop"
diff --git a/activerecord/test/cases/multiparameter_attributes_test.rb b/activerecord/test/cases/multiparameter_attributes_test.rb
index ceb5724377..7a35b5dc84 100644
--- a/activerecord/test/cases/multiparameter_attributes_test.rb
+++ b/activerecord/test/cases/multiparameter_attributes_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/customer"
diff --git a/activerecord/test/cases/multiple_db_test.rb b/activerecord/test/cases/multiple_db_test.rb
index e3bb51bd77..bfa5da765b 100644
--- a/activerecord/test/cases/multiple_db_test.rb
+++ b/activerecord/test/cases/multiple_db_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/entrant"
 require "models/bird"
diff --git a/activerecord/test/cases/nested_attributes_test.rb b/activerecord/test/cases/nested_attributes_test.rb
index 154faa56aa..aea65a7baf 100644
--- a/activerecord/test/cases/nested_attributes_test.rb
+++ b/activerecord/test/cases/nested_attributes_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/pirate"
 require "models/ship"
diff --git a/activerecord/test/cases/nested_attributes_with_callbacks_test.rb b/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
index b9d2acbed2..905ddef063 100644
--- a/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
+++ b/activerecord/test/cases/nested_attributes_with_callbacks_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/pirate"
 require "models/bird"
diff --git a/activerecord/test/cases/numeric_data_test.rb b/activerecord/test/cases/numeric_data_test.rb
index 76b97033af..b0a3d566bb 100644
--- a/activerecord/test/cases/numeric_data_test.rb
+++ b/activerecord/test/cases/numeric_data_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/numeric_data"
 
diff --git a/activerecord/test/cases/persistence_test.rb b/activerecord/test/cases/persistence_test.rb
index 5895c51714..8f0099ee48 100644
--- a/activerecord/test/cases/persistence_test.rb
+++ b/activerecord/test/cases/persistence_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/aircraft"
 require "models/post"
diff --git a/activerecord/test/cases/pooled_connections_test.rb b/activerecord/test/cases/pooled_connections_test.rb
index f1b0d08765..d99318f1aa 100644
--- a/activerecord/test/cases/pooled_connections_test.rb
+++ b/activerecord/test/cases/pooled_connections_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/project"
 require "timeout"
diff --git a/activerecord/test/cases/primary_keys_test.rb b/activerecord/test/cases/primary_keys_test.rb
index 56229b70bc..61cd6b45a1 100644
--- a/activerecord/test/cases/primary_keys_test.rb
+++ b/activerecord/test/cases/primary_keys_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 require "models/topic"
diff --git a/activerecord/test/cases/query_cache_test.rb b/activerecord/test/cases/query_cache_test.rb
index b018a7b6c0..fb5305d288 100644
--- a/activerecord/test/cases/query_cache_test.rb
+++ b/activerecord/test/cases/query_cache_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/task"
diff --git a/activerecord/test/cases/quoting_test.rb b/activerecord/test/cases/quoting_test.rb
index 0819776fbf..4cfad9c21f 100644
--- a/activerecord/test/cases/quoting_test.rb
+++ b/activerecord/test/cases/quoting_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/readonly_test.rb b/activerecord/test/cases/readonly_test.rb
index 24b678310d..2e8d108985 100644
--- a/activerecord/test/cases/readonly_test.rb
+++ b/activerecord/test/cases/readonly_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/post"
diff --git a/activerecord/test/cases/reaper_test.rb b/activerecord/test/cases/reaper_test.rb
index 249878b67d..153311bece 100644
--- a/activerecord/test/cases/reaper_test.rb
+++ b/activerecord/test/cases/reaper_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/reflection_test.rb b/activerecord/test/cases/reflection_test.rb
index c1c2efb9c8..e27000472c 100644
--- a/activerecord/test/cases/reflection_test.rb
+++ b/activerecord/test/cases/reflection_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/customer"
diff --git a/activerecord/test/cases/relation/delegation_test.rb b/activerecord/test/cases/relation/delegation_test.rb
index 3b15f051b2..5945eab75a 100644
--- a/activerecord/test/cases/relation/delegation_test.rb
+++ b/activerecord/test/cases/relation/delegation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/relation/merging_test.rb b/activerecord/test/cases/relation/merging_test.rb
index 3901824aac..feb5604284 100644
--- a/activerecord/test/cases/relation/merging_test.rb
+++ b/activerecord/test/cases/relation/merging_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/comment"
diff --git a/activerecord/test/cases/relation/mutation_test.rb b/activerecord/test/cases/relation/mutation_test.rb
index dea787c07f..113ddaa780 100644
--- a/activerecord/test/cases/relation/mutation_test.rb
+++ b/activerecord/test/cases/relation/mutation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 
diff --git a/activerecord/test/cases/relation/or_test.rb b/activerecord/test/cases/relation/or_test.rb
index 61b6601580..541feabeb6 100644
--- a/activerecord/test/cases/relation/or_test.rb
+++ b/activerecord/test/cases/relation/or_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 
diff --git a/activerecord/test/cases/relation/predicate_builder_test.rb b/activerecord/test/cases/relation/predicate_builder_test.rb
index 48758dc148..94cd704a14 100644
--- a/activerecord/test/cases/relation/predicate_builder_test.rb
+++ b/activerecord/test/cases/relation/predicate_builder_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/relation/record_fetch_warning_test.rb b/activerecord/test/cases/relation/record_fetch_warning_test.rb
index 62ca051431..59eb524f5a 100644
--- a/activerecord/test/cases/relation/record_fetch_warning_test.rb
+++ b/activerecord/test/cases/relation/record_fetch_warning_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "active_record/relation/record_fetch_warning"
diff --git a/activerecord/test/cases/relation/where_chain_test.rb b/activerecord/test/cases/relation/where_chain_test.rb
index 86e150ed79..351e955947 100644
--- a/activerecord/test/cases/relation/where_chain_test.rb
+++ b/activerecord/test/cases/relation/where_chain_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/relation/where_clause_test.rb b/activerecord/test/cases/relation/where_clause_test.rb
index f8eb0dee91..59a7002774 100644
--- a/activerecord/test/cases/relation/where_clause_test.rb
+++ b/activerecord/test/cases/relation/where_clause_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class ActiveRecord::Relation
diff --git a/activerecord/test/cases/relation/where_test.rb b/activerecord/test/cases/relation/where_test.rb
index 42dae4d569..ac4fcfff1d 100644
--- a/activerecord/test/cases/relation/where_test.rb
+++ b/activerecord/test/cases/relation/where_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/author"
 require "models/binary"
diff --git a/activerecord/test/cases/relation_test.rb b/activerecord/test/cases/relation_test.rb
index a403824f1a..f81b155657 100644
--- a/activerecord/test/cases/relation_test.rb
+++ b/activerecord/test/cases/relation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 5767dec315..c804bbf3a5 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/tag"
 require "models/tagging"
diff --git a/activerecord/test/cases/reload_models_test.rb b/activerecord/test/cases/reload_models_test.rb
index 3f4c0c03e3..6c2f9fb5ab 100644
--- a/activerecord/test/cases/reload_models_test.rb
+++ b/activerecord/test/cases/reload_models_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/owner"
 require "models/pet"
diff --git a/activerecord/test/cases/reserved_word_test.rb b/activerecord/test/cases/reserved_word_test.rb
index f3019a5326..44f7a28215 100644
--- a/activerecord/test/cases/reserved_word_test.rb
+++ b/activerecord/test/cases/reserved_word_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class ReservedWordTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/result_test.rb b/activerecord/test/cases/result_test.rb
index 1a0b7c6ca7..b4044acd57 100644
--- a/activerecord/test/cases/result_test.rb
+++ b/activerecord/test/cases/result_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/sanitize_test.rb b/activerecord/test/cases/sanitize_test.rb
index 72f09186e2..a0e7f4ae60 100644
--- a/activerecord/test/cases/sanitize_test.rb
+++ b/activerecord/test/cases/sanitize_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/binary"
 require "models/author"
diff --git a/activerecord/test/cases/schema_dumper_test.rb b/activerecord/test/cases/schema_dumper_test.rb
index 4c81e825fa..86a0e93832 100644
--- a/activerecord/test/cases/schema_dumper_test.rb
+++ b/activerecord/test/cases/schema_dumper_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/schema_loading_test.rb b/activerecord/test/cases/schema_loading_test.rb
index 362370ac61..e3b7755f07 100644
--- a/activerecord/test/cases/schema_loading_test.rb
+++ b/activerecord/test/cases/schema_loading_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module SchemaLoadCounter
diff --git a/activerecord/test/cases/scoping/default_scoping_test.rb b/activerecord/test/cases/scoping/default_scoping_test.rb
index 89fb434b27..9919ed5e3f 100644
--- a/activerecord/test/cases/scoping/default_scoping_test.rb
+++ b/activerecord/test/cases/scoping/default_scoping_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/comment"
diff --git a/activerecord/test/cases/scoping/named_scoping_test.rb b/activerecord/test/cases/scoping/named_scoping_test.rb
index 483ea7128d..ea338a9847 100644
--- a/activerecord/test/cases/scoping/named_scoping_test.rb
+++ b/activerecord/test/cases/scoping/named_scoping_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/topic"
diff --git a/activerecord/test/cases/scoping/relation_scoping_test.rb b/activerecord/test/cases/scoping/relation_scoping_test.rb
index 10553bf057..644e7eb692 100644
--- a/activerecord/test/cases/scoping/relation_scoping_test.rb
+++ b/activerecord/test/cases/scoping/relation_scoping_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/post"
 require "models/author"
diff --git a/activerecord/test/cases/secure_token_test.rb b/activerecord/test/cases/secure_token_test.rb
index 7b9cbee40a..987ae3074f 100644
--- a/activerecord/test/cases/secure_token_test.rb
+++ b/activerecord/test/cases/secure_token_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/user"
 
diff --git a/activerecord/test/cases/serialization_test.rb b/activerecord/test/cases/serialization_test.rb
index ec33ad38f2..82e0311d84 100644
--- a/activerecord/test/cases/serialization_test.rb
+++ b/activerecord/test/cases/serialization_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/contact"
 require "models/topic"
diff --git a/activerecord/test/cases/serialized_attribute_test.rb b/activerecord/test/cases/serialized_attribute_test.rb
index e1bdaab5cf..6525730350 100644
--- a/activerecord/test/cases/serialized_attribute_test.rb
+++ b/activerecord/test/cases/serialized_attribute_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/statement_cache_test.rb b/activerecord/test/cases/statement_cache_test.rb
index fab3648564..ee1a8bfc36 100644
--- a/activerecord/test/cases/statement_cache_test.rb
+++ b/activerecord/test/cases/statement_cache_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/book"
 require "models/liquid"
diff --git a/activerecord/test/cases/store_test.rb b/activerecord/test/cases/store_test.rb
index 633a8a0ebc..0ece0632fe 100644
--- a/activerecord/test/cases/store_test.rb
+++ b/activerecord/test/cases/store_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/admin"
 require "models/admin/user"
diff --git a/activerecord/test/cases/suppressor_test.rb b/activerecord/test/cases/suppressor_test.rb
index a7d16b7cdb..bc85461322 100644
--- a/activerecord/test/cases/suppressor_test.rb
+++ b/activerecord/test/cases/suppressor_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/notification"
 require "models/user"
diff --git a/activerecord/test/cases/tasks/database_tasks_test.rb b/activerecord/test/cases/tasks/database_tasks_test.rb
index c47c97e9d9..b8280c4aaf 100644
--- a/activerecord/test/cases/tasks/database_tasks_test.rb
+++ b/activerecord/test/cases/tasks/database_tasks_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/tasks/database_tasks"
 
diff --git a/activerecord/test/cases/tasks/mysql_rake_test.rb b/activerecord/test/cases/tasks/mysql_rake_test.rb
index 9c6fb14376..02c0cfbb92 100644
--- a/activerecord/test/cases/tasks/mysql_rake_test.rb
+++ b/activerecord/test/cases/tasks/mysql_rake_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/tasks/database_tasks"
 
diff --git a/activerecord/test/cases/tasks/postgresql_rake_test.rb b/activerecord/test/cases/tasks/postgresql_rake_test.rb
index a2e968aedf..9369d1eedb 100644
--- a/activerecord/test/cases/tasks/postgresql_rake_test.rb
+++ b/activerecord/test/cases/tasks/postgresql_rake_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/tasks/database_tasks"
 
diff --git a/activerecord/test/cases/tasks/sqlite_rake_test.rb b/activerecord/test/cases/tasks/sqlite_rake_test.rb
index ccb3834fee..0deedad671 100644
--- a/activerecord/test/cases/tasks/sqlite_rake_test.rb
+++ b/activerecord/test/cases/tasks/sqlite_rake_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "active_record/tasks/database_tasks"
 require "pathname"
diff --git a/activerecord/test/cases/test_case.rb b/activerecord/test/cases/test_case.rb
index 9f594fef85..247d0ec3d1 100644
--- a/activerecord/test/cases/test_case.rb
+++ b/activerecord/test/cases/test_case.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/test_case"
 require "active_support/testing/autorun"
 require "active_support/testing/method_call_assertions"
diff --git a/activerecord/test/cases/test_fixtures_test.rb b/activerecord/test/cases/test_fixtures_test.rb
index 58d3bea3a2..e542716563 100644
--- a/activerecord/test/cases/test_fixtures_test.rb
+++ b/activerecord/test/cases/test_fixtures_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class TestFixturesTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/time_precision_test.rb b/activerecord/test/cases/time_precision_test.rb
index 09c585167e..3a8f8af0e6 100644
--- a/activerecord/test/cases/time_precision_test.rb
+++ b/activerecord/test/cases/time_precision_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/schema_dumping_helper"
 
diff --git a/activerecord/test/cases/timestamp_test.rb b/activerecord/test/cases/timestamp_test.rb
index 39b40e3411..0f58c96504 100644
--- a/activerecord/test/cases/timestamp_test.rb
+++ b/activerecord/test/cases/timestamp_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "support/ddl_helper"
 require "models/developer"
diff --git a/activerecord/test/cases/touch_later_test.rb b/activerecord/test/cases/touch_later_test.rb
index d1e8c649d9..24b5e8886f 100644
--- a/activerecord/test/cases/touch_later_test.rb
+++ b/activerecord/test/cases/touch_later_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/invoice"
 require "models/line_item"
diff --git a/activerecord/test/cases/transaction_callbacks_test.rb b/activerecord/test/cases/transaction_callbacks_test.rb
index eaa4dd09a9..aa0d8f5e65 100644
--- a/activerecord/test/cases/transaction_callbacks_test.rb
+++ b/activerecord/test/cases/transaction_callbacks_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/owner"
 require "models/pet"
diff --git a/activerecord/test/cases/transaction_isolation_test.rb b/activerecord/test/cases/transaction_isolation_test.rb
index 58abfadaf4..380d7dbb0a 100644
--- a/activerecord/test/cases/transaction_isolation_test.rb
+++ b/activerecord/test/cases/transaction_isolation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 unless ActiveRecord::Base.connection.supports_transaction_isolation?
diff --git a/activerecord/test/cases/transactions_test.rb b/activerecord/test/cases/transactions_test.rb
index 79ba306ef5..ced6045955 100644
--- a/activerecord/test/cases/transactions_test.rb
+++ b/activerecord/test/cases/transactions_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/type/adapter_specific_registry_test.rb b/activerecord/test/cases/type/adapter_specific_registry_test.rb
index 8b836b4793..a723a952ea 100644
--- a/activerecord/test/cases/type/adapter_specific_registry_test.rb
+++ b/activerecord/test/cases/type/adapter_specific_registry_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/type/date_time_test.rb b/activerecord/test/cases/type/date_time_test.rb
index 6848619ece..9307587564 100644
--- a/activerecord/test/cases/type/date_time_test.rb
+++ b/activerecord/test/cases/type/date_time_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/task"
 
diff --git a/activerecord/test/cases/type/integer_test.rb b/activerecord/test/cases/type/integer_test.rb
index 368b6d7199..13d6d2093b 100644
--- a/activerecord/test/cases/type/integer_test.rb
+++ b/activerecord/test/cases/type/integer_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/company"
 
diff --git a/activerecord/test/cases/type/string_test.rb b/activerecord/test/cases/type/string_test.rb
index a95da864fa..899d7ae767 100644
--- a/activerecord/test/cases/type/string_test.rb
+++ b/activerecord/test/cases/type/string_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/type/type_map_test.rb b/activerecord/test/cases/type/type_map_test.rb
index 2959d36466..f171175b2a 100644
--- a/activerecord/test/cases/type/type_map_test.rb
+++ b/activerecord/test/cases/type/type_map_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/type/unsigned_integer_test.rb b/activerecord/test/cases/type/unsigned_integer_test.rb
index 1cd4dbc2c5..b0a60a2b3d 100644
--- a/activerecord/test/cases/type/unsigned_integer_test.rb
+++ b/activerecord/test/cases/type/unsigned_integer_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/type_test.rb b/activerecord/test/cases/type_test.rb
index d45a9b3141..0f9f698760 100644
--- a/activerecord/test/cases/type_test.rb
+++ b/activerecord/test/cases/type_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class TypeTest < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/types_test.rb b/activerecord/test/cases/types_test.rb
index 11476ea0ef..ea55bb00cd 100644
--- a/activerecord/test/cases/types_test.rb
+++ b/activerecord/test/cases/types_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 module ActiveRecord
diff --git a/activerecord/test/cases/unconnected_test.rb b/activerecord/test/cases/unconnected_test.rb
index b210584644..30efd03955 100644
--- a/activerecord/test/cases/unconnected_test.rb
+++ b/activerecord/test/cases/unconnected_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 
 class TestRecord < ActiveRecord::Base
diff --git a/activerecord/test/cases/validations/absence_validation_test.rb b/activerecord/test/cases/validations/absence_validation_test.rb
index 870619e4e7..051f14dbb7 100644
--- a/activerecord/test/cases/validations/absence_validation_test.rb
+++ b/activerecord/test/cases/validations/absence_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/face"
 require "models/interest"
diff --git a/activerecord/test/cases/validations/association_validation_test.rb b/activerecord/test/cases/validations/association_validation_test.rb
index f5ceb27d97..0935dc8c32 100644
--- a/activerecord/test/cases/validations/association_validation_test.rb
+++ b/activerecord/test/cases/validations/association_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
index a57065ba75..fdfd568897 100644
--- a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
+++ b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 
diff --git a/activerecord/test/cases/validations/i18n_validation_test.rb b/activerecord/test/cases/validations/i18n_validation_test.rb
index fd88a3ea67..a020c877e7 100644
--- a/activerecord/test/cases/validations/i18n_validation_test.rb
+++ b/activerecord/test/cases/validations/i18n_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/validations/length_validation_test.rb b/activerecord/test/cases/validations/length_validation_test.rb
index ba45c6dcc1..7f840dfa7c 100644
--- a/activerecord/test/cases/validations/length_validation_test.rb
+++ b/activerecord/test/cases/validations/length_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/owner"
 require "models/pet"
diff --git a/activerecord/test/cases/validations/presence_validation_test.rb b/activerecord/test/cases/validations/presence_validation_test.rb
index 13956e26ec..dee8528124 100644
--- a/activerecord/test/cases/validations/presence_validation_test.rb
+++ b/activerecord/test/cases/validations/presence_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/man"
 require "models/face"
diff --git a/activerecord/test/cases/validations/uniqueness_validation_test.rb b/activerecord/test/cases/validations/uniqueness_validation_test.rb
index 28605d2f8e..e943d03720 100644
--- a/activerecord/test/cases/validations/uniqueness_validation_test.rb
+++ b/activerecord/test/cases/validations/uniqueness_validation_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/validations_repair_helper.rb b/activerecord/test/cases/validations_repair_helper.rb
index b30666d876..30299fd2c6 100644
--- a/activerecord/test/cases/validations_repair_helper.rb
+++ b/activerecord/test/cases/validations_repair_helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ActiveRecord
   module ValidationsRepairHelper
     extend ActiveSupport::Concern
diff --git a/activerecord/test/cases/validations_test.rb b/activerecord/test/cases/validations_test.rb
index a305aa295a..fc9678211a 100644
--- a/activerecord/test/cases/validations_test.rb
+++ b/activerecord/test/cases/validations_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/cases/view_test.rb b/activerecord/test/cases/view_test.rb
index 1d21a2454f..89b72ec336 100644
--- a/activerecord/test/cases/view_test.rb
+++ b/activerecord/test/cases/view_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/book"
 require "support/schema_dumping_helper"
diff --git a/activerecord/test/cases/yaml_serialization_test.rb b/activerecord/test/cases/yaml_serialization_test.rb
index bfc13d683d..6b9f632f22 100644
--- a/activerecord/test/cases/yaml_serialization_test.rb
+++ b/activerecord/test/cases/yaml_serialization_test.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "cases/helper"
 require "models/topic"
 require "models/reply"
diff --git a/activerecord/test/config.rb b/activerecord/test/config.rb
index a65e6ff776..d0d1933300 100644
--- a/activerecord/test/config.rb
+++ b/activerecord/test/config.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 TEST_ROOT       = __dir__
 ASSETS_ROOT     = TEST_ROOT + "/assets"
 FIXTURES_ROOT   = TEST_ROOT + "/fixtures"
diff --git a/activerecord/test/migrations/10_urban/9_add_expressions.rb b/activerecord/test/migrations/10_urban/9_add_expressions.rb
index e908c9eabc..db9fda3e05 100644
--- a/activerecord/test/migrations/10_urban/9_add_expressions.rb
+++ b/activerecord/test/migrations/10_urban/9_add_expressions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class AddExpressions < ActiveRecord::Migration::Current
   def self.up
     create_table("expressions") do |t|
diff --git a/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb b/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
index 43c79bc20b..f13f72eb4e 100644
--- a/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
+++ b/activerecord/test/migrations/decimal/1_give_me_big_numbers.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class GiveMeBigNumbers < ActiveRecord::Migration::Current
   def self.up
     create_table :big_numbers do |table|
diff --git a/activerecord/test/migrations/magic/1_currencies_have_symbols.rb b/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
index d4b0e6cd95..d8a864b213 100644
--- a/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
+++ b/activerecord/test/migrations/magic/1_currencies_have_symbols.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
 # coding: ISO-8859-15
 
 class CurrenciesHaveSymbols < ActiveRecord::Migration::Current
   def self.up
-    # We use € for default currency symbol
-    add_column "currencies", "symbol", :string, default: "€"
+    # We use â¬ for default currency symbol
+    add_column "currencies", "symbol", :string, default: "â¬"
   end
 
   def self.down
diff --git a/activerecord/test/migrations/missing/1000_people_have_middle_names.rb b/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
index e046944e31..a1a5dcbac2 100644
--- a/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
+++ b/activerecord/test/migrations/missing/1000_people_have_middle_names.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveMiddleNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "middle_name", :string
diff --git a/activerecord/test/migrations/missing/1_people_have_last_names.rb b/activerecord/test/migrations/missing/1_people_have_last_names.rb
index 50fe2a9c8e..1480b4b8f3 100644
--- a/activerecord/test/migrations/missing/1_people_have_last_names.rb
+++ b/activerecord/test/migrations/missing/1_people_have_last_names.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/missing/3_we_need_reminders.rb b/activerecord/test/migrations/missing/3_we_need_reminders.rb
index d7c63ac892..e69296a31f 100644
--- a/activerecord/test/migrations/missing/3_we_need_reminders.rb
+++ b/activerecord/test/migrations/missing/3_we_need_reminders.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/missing/4_innocent_jointable.rb b/activerecord/test/migrations/missing/4_innocent_jointable.rb
index bd3bf21576..0c021c6162 100644
--- a/activerecord/test/migrations/missing/4_innocent_jointable.rb
+++ b/activerecord/test/migrations/missing/4_innocent_jointable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
     create_table("people_reminders", id: false) do |t|
diff --git a/activerecord/test/migrations/rename/1_we_need_things.rb b/activerecord/test/migrations/rename/1_we_need_things.rb
index 9dce01acfd..411d6f9646 100644
--- a/activerecord/test/migrations/rename/1_we_need_things.rb
+++ b/activerecord/test/migrations/rename/1_we_need_things.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WeNeedThings < ActiveRecord::Migration::Current
   def self.up
     create_table("things") do |t|
diff --git a/activerecord/test/migrations/rename/2_rename_things.rb b/activerecord/test/migrations/rename/2_rename_things.rb
index cb8484e7dc..99b1cec7f5 100644
--- a/activerecord/test/migrations/rename/2_rename_things.rb
+++ b/activerecord/test/migrations/rename/2_rename_things.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class RenameThings < ActiveRecord::Migration::Current
   def self.up
     rename_table "things", "awesome_things"
diff --git a/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb b/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
index 76734bcd7d..65b92fbb85 100644
--- a/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy/1_people_have_hobbies.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :text
diff --git a/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb b/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
index 7f883dbb45..7a3bede29a 100644
--- a/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
+++ b/activerecord/test/migrations/to_copy/2_people_have_descriptions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveDescriptions < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "description", :text
diff --git a/activerecord/test/migrations/to_copy2/1_create_articles.rb b/activerecord/test/migrations/to_copy2/1_create_articles.rb
index 2e9f5ec6bc..3a82d15aea 100644
--- a/activerecord/test/migrations/to_copy2/1_create_articles.rb
+++ b/activerecord/test/migrations/to_copy2/1_create_articles.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CreateArticles < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy2/2_create_comments.rb b/activerecord/test/migrations/to_copy2/2_create_comments.rb
index d361847d4b..fb1032f8dd 100644
--- a/activerecord/test/migrations/to_copy2/2_create_comments.rb
+++ b/activerecord/test/migrations/to_copy2/2_create_comments.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CreateComments < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb b/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
index 1a863367dd..ea106d5be4 100644
--- a/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy_with_name_collision/1_people_have_hobbies.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :string
diff --git a/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb b/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
index 76734bcd7d..65b92fbb85 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps/20090101010101_people_have_hobbies.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveHobbies < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "hobbies", :text
diff --git a/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb b/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
index 7f883dbb45..7a3bede29a 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps/20090101010202_people_have_descriptions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PeopleHaveDescriptions < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "description", :text
diff --git a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
index 2e9f5ec6bc..3a82d15aea 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010101_create_articles.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CreateArticles < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
index d361847d4b..fb1032f8dd 100644
--- a/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
+++ b/activerecord/test/migrations/to_copy_with_timestamps2/20090101010202_create_comments.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CreateComments < ActiveRecord::Migration::Current
   def self.up
   end
diff --git a/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb b/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
index c450211d8c..1d2193469c 100644
--- a/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid/1_valid_people_have_last_names.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ValidPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid/2_we_need_reminders.rb b/activerecord/test/migrations/valid/2_we_need_reminders.rb
index d7c63ac892..e69296a31f 100644
--- a/activerecord/test/migrations/valid/2_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid/2_we_need_reminders.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid/3_innocent_jointable.rb b/activerecord/test/migrations/valid/3_innocent_jointable.rb
index bd3bf21576..0c021c6162 100644
--- a/activerecord/test/migrations/valid/3_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid/3_innocent_jointable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
     create_table("people_reminders", id: false) do |t|
diff --git a/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb b/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
index c450211d8c..1d2193469c 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/1_valid_people_have_last_names.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ValidPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb b/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
index d7c63ac892..e69296a31f 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/sub/2_we_need_reminders.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb b/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
index bd3bf21576..0c021c6162 100644
--- a/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid_with_subdirectories/sub1/3_innocent_jointable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class InnocentJointable < ActiveRecord::Migration::Current
   def self.up
     create_table("people_reminders", id: false) do |t|
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb b/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
index 9fd27593f0..f7ef1a9769 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100101010101_valid_with_timestamps_people_have_last_names.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ValidWithTimestampsPeopleHaveLastNames < ActiveRecord::Migration::Current
   def self.up
     add_column "people", "last_name", :string
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb b/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
index 4a59921136..7732032c5d 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100201010101_valid_with_timestamps_we_need_reminders.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ValidWithTimestampsWeNeedReminders < ActiveRecord::Migration::Current
   def self.up
     create_table("reminders") do |t|
diff --git a/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb b/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
index be24de6d70..cf652c008a 100644
--- a/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
+++ b/activerecord/test/migrations/valid_with_timestamps/20100301010101_valid_with_timestamps_innocent_jointable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ValidWithTimestampsInnocentJointable < ActiveRecord::Migration::Current
   def self.up
     create_table("people_reminders", id: false) do |t|
diff --git a/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb b/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
index 6f314c881c..ceb0cc98bf 100644
--- a/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
+++ b/activerecord/test/migrations/version_check/20131219224947_migration_version_check.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class MigrationVersionCheck < ActiveRecord::Migration::Current
   def self.up
     raise "incorrect migration version" unless version == 20131219224947
diff --git a/activerecord/test/models/admin.rb b/activerecord/test/models/admin.rb
index bc3ce23447..6c8a6eddb0 100644
--- a/activerecord/test/models/admin.rb
+++ b/activerecord/test/models/admin.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Admin
   def self.table_name_prefix
     "admin_"
diff --git a/activerecord/test/models/admin/account.rb b/activerecord/test/models/admin/account.rb
index bd23192d20..2dddfa8fe9 100644
--- a/activerecord/test/models/admin/account.rb
+++ b/activerecord/test/models/admin/account.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Admin::Account < ActiveRecord::Base
   has_many :users
 end
diff --git a/activerecord/test/models/admin/randomly_named_c1.rb b/activerecord/test/models/admin/randomly_named_c1.rb
index b64ae7fc41..dc1c8c66d7 100644
--- a/activerecord/test/models/admin/randomly_named_c1.rb
+++ b/activerecord/test/models/admin/randomly_named_c1.rb
@@ -1,7 +1,8 @@
-class Admin::ClassNameThatDoesNotFollowCONVENTIONS1 < ActiveRecord::Base
-  self.table_name = :randomly_named_table2
-end
-
-class Admin::ClassNameThatDoesNotFollowCONVENTIONS2 < ActiveRecord::Base
-  self.table_name = :randomly_named_table3
-end
+# frozen_string_literal: true
+class Admin::ClassNameThatDoesNotFollowCONVENTIONS1 < ActiveRecord::Base
+  self.table_name = :randomly_named_table2
+end
+
+class Admin::ClassNameThatDoesNotFollowCONVENTIONS2 < ActiveRecord::Base
+  self.table_name = :randomly_named_table3
+end
diff --git a/activerecord/test/models/admin/user.rb b/activerecord/test/models/admin/user.rb
index a76e4b6795..1157ca266c 100644
--- a/activerecord/test/models/admin/user.rb
+++ b/activerecord/test/models/admin/user.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Admin::User < ActiveRecord::Base
   class Coder
     def initialize(default = {})
diff --git a/activerecord/test/models/aircraft.rb b/activerecord/test/models/aircraft.rb
index ebd42ff824..02421afe34 100644
--- a/activerecord/test/models/aircraft.rb
+++ b/activerecord/test/models/aircraft.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Aircraft < ActiveRecord::Base
   self.pluralize_table_names = false
   has_many :engines, foreign_key: "car_id"
diff --git a/activerecord/test/models/arunit2_model.rb b/activerecord/test/models/arunit2_model.rb
index 04b8b15d3d..80a8ecc5d8 100644
--- a/activerecord/test/models/arunit2_model.rb
+++ b/activerecord/test/models/arunit2_model.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ARUnit2Model < ActiveRecord::Base
   self.abstract_class = true
 end
diff --git a/activerecord/test/models/author.rb b/activerecord/test/models/author.rb
index 2d9cba77e0..c3278846d6 100644
--- a/activerecord/test/models/author.rb
+++ b/activerecord/test/models/author.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Author < ActiveRecord::Base
   has_many :posts
   has_many :serialized_posts
diff --git a/activerecord/test/models/auto_id.rb b/activerecord/test/models/auto_id.rb
index 82c6544bd5..56479b49eb 100644
--- a/activerecord/test/models/auto_id.rb
+++ b/activerecord/test/models/auto_id.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class AutoId < ActiveRecord::Base
   self.table_name = "auto_id_tests"
   self.primary_key = "auto_id"
diff --git a/activerecord/test/models/autoloadable/extra_firm.rb b/activerecord/test/models/autoloadable/extra_firm.rb
index 5578ba0d9b..54c421e459 100644
--- a/activerecord/test/models/autoloadable/extra_firm.rb
+++ b/activerecord/test/models/autoloadable/extra_firm.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class ExtraFirm < Company
 end
diff --git a/activerecord/test/models/binary.rb b/activerecord/test/models/binary.rb
index 39b2f5090a..4b1212705b 100644
--- a/activerecord/test/models/binary.rb
+++ b/activerecord/test/models/binary.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Binary < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/bird.rb b/activerecord/test/models/bird.rb
index 24b839135d..ba923b4316 100644
--- a/activerecord/test/models/bird.rb
+++ b/activerecord/test/models/bird.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Bird < ActiveRecord::Base
   belongs_to :pirate
   validates_presence_of :name
diff --git a/activerecord/test/models/book.rb b/activerecord/test/models/book.rb
index 6466e1b341..46d5d94da3 100644
--- a/activerecord/test/models/book.rb
+++ b/activerecord/test/models/book.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Book < ActiveRecord::Base
   belongs_to :author
 
diff --git a/activerecord/test/models/boolean.rb b/activerecord/test/models/boolean.rb
index 0da228aac2..e2f1bb8a9a 100644
--- a/activerecord/test/models/boolean.rb
+++ b/activerecord/test/models/boolean.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Boolean < ActiveRecord::Base
   def has_fun
     super
diff --git a/activerecord/test/models/bulb.rb b/activerecord/test/models/bulb.rb
index 113d21cb84..ad9806db55 100644
--- a/activerecord/test/models/bulb.rb
+++ b/activerecord/test/models/bulb.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Bulb < ActiveRecord::Base
   default_scope { where(name: "defaulty") }
   belongs_to :car, touch: true
diff --git a/activerecord/test/models/cake_designer.rb b/activerecord/test/models/cake_designer.rb
index 9c57ef573a..20fa26a556 100644
--- a/activerecord/test/models/cake_designer.rb
+++ b/activerecord/test/models/cake_designer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CakeDesigner < ActiveRecord::Base
   has_one :chef, as: :employable
 end
diff --git a/activerecord/test/models/car.rb b/activerecord/test/models/car.rb
index 92bff7ff96..3c3d9295b0 100644
--- a/activerecord/test/models/car.rb
+++ b/activerecord/test/models/car.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Car < ActiveRecord::Base
   has_many :bulbs
   has_many :all_bulbs, -> { unscope where: :name }, class_name: "Bulb"
diff --git a/activerecord/test/models/carrier.rb b/activerecord/test/models/carrier.rb
index 230be118c3..bf8055fbd7 100644
--- a/activerecord/test/models/carrier.rb
+++ b/activerecord/test/models/carrier.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Carrier < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/cat.rb b/activerecord/test/models/cat.rb
index dfdde18641..4c76ec86cf 100644
--- a/activerecord/test/models/cat.rb
+++ b/activerecord/test/models/cat.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Cat < ActiveRecord::Base
   self.abstract_class = true
 
diff --git a/activerecord/test/models/categorization.rb b/activerecord/test/models/categorization.rb
index b99383d0b1..87b81e1e2d 100644
--- a/activerecord/test/models/categorization.rb
+++ b/activerecord/test/models/categorization.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Categorization < ActiveRecord::Base
   belongs_to :post
   belongs_to :category, counter_cache: true
diff --git a/activerecord/test/models/category.rb b/activerecord/test/models/category.rb
index 4b2840c653..392fe94fe7 100644
--- a/activerecord/test/models/category.rb
+++ b/activerecord/test/models/category.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Category < ActiveRecord::Base
   has_and_belongs_to_many :posts
   has_and_belongs_to_many :special_posts, class_name: "Post"
diff --git a/activerecord/test/models/chef.rb b/activerecord/test/models/chef.rb
index 9d3dd01016..daa208ff5f 100644
--- a/activerecord/test/models/chef.rb
+++ b/activerecord/test/models/chef.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Chef < ActiveRecord::Base
   belongs_to :employable, polymorphic: true
   has_many :recipes
diff --git a/activerecord/test/models/citation.rb b/activerecord/test/models/citation.rb
index 7d06387f56..8a6c300a28 100644
--- a/activerecord/test/models/citation.rb
+++ b/activerecord/test/models/citation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Citation < ActiveRecord::Base
   belongs_to :reference_of, class_name: "Book", foreign_key: :book2_id
 end
diff --git a/activerecord/test/models/club.rb b/activerecord/test/models/club.rb
index 49d7b24a3b..cdd5b37792 100644
--- a/activerecord/test/models/club.rb
+++ b/activerecord/test/models/club.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Club < ActiveRecord::Base
   has_one :membership
   has_many :memberships, inverse_of: false
diff --git a/activerecord/test/models/college.rb b/activerecord/test/models/college.rb
index c9dbe1ecc2..70c0cd1534 100644
--- a/activerecord/test/models/college.rb
+++ b/activerecord/test/models/college.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require_dependency "models/arunit2_model"
 require "active_support/core_ext/object/with_options"
 
diff --git a/activerecord/test/models/column.rb b/activerecord/test/models/column.rb
index 499358b4cf..08e1a4ae2d 100644
--- a/activerecord/test/models/column.rb
+++ b/activerecord/test/models/column.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Column < ActiveRecord::Base
   belongs_to :record
 end
diff --git a/activerecord/test/models/column_name.rb b/activerecord/test/models/column_name.rb
index 460eb4fe20..3b4452c3c2 100644
--- a/activerecord/test/models/column_name.rb
+++ b/activerecord/test/models/column_name.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ColumnName < ActiveRecord::Base
   self.table_name = "colnametests"
 end
diff --git a/activerecord/test/models/comment.rb b/activerecord/test/models/comment.rb
index eecf923046..6c10ec0858 100644
--- a/activerecord/test/models/comment.rb
+++ b/activerecord/test/models/comment.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Comment < ActiveRecord::Base
   scope :limit_by, lambda { |l| limit(l) }
   scope :containing_the_letter_e, -> { where("comments.body LIKE '%e%'") }
diff --git a/activerecord/test/models/company.rb b/activerecord/test/models/company.rb
index c6a5bf1c92..8a6d909188 100644
--- a/activerecord/test/models/company.rb
+++ b/activerecord/test/models/company.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class AbstractCompany < ActiveRecord::Base
   self.abstract_class = true
 end
diff --git a/activerecord/test/models/company_in_module.rb b/activerecord/test/models/company_in_module.rb
index 0782c1eff4..2e7295eed1 100644
--- a/activerecord/test/models/company_in_module.rb
+++ b/activerecord/test/models/company_in_module.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/core_ext/object/with_options"
 
 module MyApplication
diff --git a/activerecord/test/models/computer.rb b/activerecord/test/models/computer.rb
index 1c9856e1af..f2998d362a 100644
--- a/activerecord/test/models/computer.rb
+++ b/activerecord/test/models/computer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Computer < ActiveRecord::Base
   belongs_to :developer, foreign_key: "developer"
 end
diff --git a/activerecord/test/models/contact.rb b/activerecord/test/models/contact.rb
index 47bbbbfd8b..0a095301bd 100644
--- a/activerecord/test/models/contact.rb
+++ b/activerecord/test/models/contact.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ContactFakeColumns
   def self.extended(base)
     base.class_eval do
diff --git a/activerecord/test/models/content.rb b/activerecord/test/models/content.rb
index 68db2127d8..f2913be22d 100644
--- a/activerecord/test/models/content.rb
+++ b/activerecord/test/models/content.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Content < ActiveRecord::Base
   self.table_name = "content"
   has_one :content_position, dependent: :destroy
diff --git a/activerecord/test/models/contract.rb b/activerecord/test/models/contract.rb
index 32bd581377..e4bace0e32 100644
--- a/activerecord/test/models/contract.rb
+++ b/activerecord/test/models/contract.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Contract < ActiveRecord::Base
   belongs_to :company
   belongs_to :developer
diff --git a/activerecord/test/models/country.rb b/activerecord/test/models/country.rb
index 7912719ddd..5c1c6dc492 100644
--- a/activerecord/test/models/country.rb
+++ b/activerecord/test/models/country.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Country < ActiveRecord::Base
   self.primary_key = :country_id
 
diff --git a/activerecord/test/models/course.rb b/activerecord/test/models/course.rb
index 348f2bf1e0..0af33ed85f 100644
--- a/activerecord/test/models/course.rb
+++ b/activerecord/test/models/course.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require_dependency "models/arunit2_model"
 
 class Course < ARUnit2Model
diff --git a/activerecord/test/models/customer.rb b/activerecord/test/models/customer.rb
index 3d40cb1ace..2eb4c720a6 100644
--- a/activerecord/test/models/customer.rb
+++ b/activerecord/test/models/customer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Customer < ActiveRecord::Base
   cattr_accessor :gps_conversion_was_run
 
diff --git a/activerecord/test/models/customer_carrier.rb b/activerecord/test/models/customer_carrier.rb
index 37186903ff..3d236da43d 100644
--- a/activerecord/test/models/customer_carrier.rb
+++ b/activerecord/test/models/customer_carrier.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class CustomerCarrier < ActiveRecord::Base
   cattr_accessor :current_customer
 
diff --git a/activerecord/test/models/dashboard.rb b/activerecord/test/models/dashboard.rb
index 1b3b54545f..fe54e9d6fc 100644
--- a/activerecord/test/models/dashboard.rb
+++ b/activerecord/test/models/dashboard.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Dashboard < ActiveRecord::Base
   self.primary_key = :dashboard_id
 end
diff --git a/activerecord/test/models/default.rb b/activerecord/test/models/default.rb
index 887e9cc999..6f87ee74f7 100644
--- a/activerecord/test/models/default.rb
+++ b/activerecord/test/models/default.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Default < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/department.rb b/activerecord/test/models/department.rb
index 08004a0ed3..e8cdae8976 100644
--- a/activerecord/test/models/department.rb
+++ b/activerecord/test/models/department.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Department < ActiveRecord::Base
   has_many :chefs
   belongs_to :hotel
diff --git a/activerecord/test/models/developer.rb b/activerecord/test/models/developer.rb
index 654830ba11..aa7798c582 100644
--- a/activerecord/test/models/developer.rb
+++ b/activerecord/test/models/developer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "ostruct"
 
 module DeveloperProjectsAssociationExtension2
diff --git a/activerecord/test/models/dog.rb b/activerecord/test/models/dog.rb
index b02b8447b8..08eeb6b75e 100644
--- a/activerecord/test/models/dog.rb
+++ b/activerecord/test/models/dog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Dog < ActiveRecord::Base
   belongs_to :breeder, class_name: "DogLover", counter_cache: :bred_dogs_count
   belongs_to :trainer, class_name: "DogLover", counter_cache: :trained_dogs_count
diff --git a/activerecord/test/models/dog_lover.rb b/activerecord/test/models/dog_lover.rb
index 2c5be94aea..75e43bda8a 100644
--- a/activerecord/test/models/dog_lover.rb
+++ b/activerecord/test/models/dog_lover.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class DogLover < ActiveRecord::Base
   has_many :trained_dogs, class_name: "Dog", foreign_key: :trainer_id, dependent: :destroy
   has_many :bred_dogs, class_name: "Dog", foreign_key: :breeder_id
diff --git a/activerecord/test/models/doubloon.rb b/activerecord/test/models/doubloon.rb
index 7272504666..e18868e022 100644
--- a/activerecord/test/models/doubloon.rb
+++ b/activerecord/test/models/doubloon.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class AbstractDoubloon < ActiveRecord::Base
   # This has functionality that might be shared by multiple classes.
 
diff --git a/activerecord/test/models/drink_designer.rb b/activerecord/test/models/drink_designer.rb
index 2db968ef11..9de6e3d618 100644
--- a/activerecord/test/models/drink_designer.rb
+++ b/activerecord/test/models/drink_designer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class DrinkDesigner < ActiveRecord::Base
   has_one :chef, as: :employable
 end
diff --git a/activerecord/test/models/edge.rb b/activerecord/test/models/edge.rb
index e61d25c9bc..9711ea6da9 100644
--- a/activerecord/test/models/edge.rb
+++ b/activerecord/test/models/edge.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # This class models an edge in a directed graph.
 class Edge < ActiveRecord::Base
   belongs_to :source, class_name: "Vertex", foreign_key: "source_id"
diff --git a/activerecord/test/models/electron.rb b/activerecord/test/models/electron.rb
index 6fc270673f..1828d173bb 100644
--- a/activerecord/test/models/electron.rb
+++ b/activerecord/test/models/electron.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Electron < ActiveRecord::Base
   belongs_to :molecule
 
diff --git a/activerecord/test/models/engine.rb b/activerecord/test/models/engine.rb
index eada171f6a..144bf7159b 100644
--- a/activerecord/test/models/engine.rb
+++ b/activerecord/test/models/engine.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Engine < ActiveRecord::Base
   belongs_to :my_car, class_name: "Car", foreign_key: "car_id",  counter_cache: :engines_count
 end
diff --git a/activerecord/test/models/entrant.rb b/activerecord/test/models/entrant.rb
index 4682ce48c8..77095e28c5 100644
--- a/activerecord/test/models/entrant.rb
+++ b/activerecord/test/models/entrant.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Entrant < ActiveRecord::Base
   belongs_to :course
 end
diff --git a/activerecord/test/models/essay.rb b/activerecord/test/models/essay.rb
index 1f9772870e..302a862907 100644
--- a/activerecord/test/models/essay.rb
+++ b/activerecord/test/models/essay.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Essay < ActiveRecord::Base
   belongs_to :author
   belongs_to :writer, primary_key: :name, polymorphic: true
diff --git a/activerecord/test/models/event.rb b/activerecord/test/models/event.rb
index 365ab32b0b..ac9bc63f34 100644
--- a/activerecord/test/models/event.rb
+++ b/activerecord/test/models/event.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Event < ActiveRecord::Base
   validates_uniqueness_of :title
 end
diff --git a/activerecord/test/models/eye.rb b/activerecord/test/models/eye.rb
index f53c34e4b1..a7410e8aa9 100644
--- a/activerecord/test/models/eye.rb
+++ b/activerecord/test/models/eye.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Eye < ActiveRecord::Base
   attr_reader :after_create_callbacks_stack
   attr_reader :after_update_callbacks_stack
diff --git a/activerecord/test/models/face.rb b/activerecord/test/models/face.rb
index 5913bfa969..3c78bf9284 100644
--- a/activerecord/test/models/face.rb
+++ b/activerecord/test/models/face.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Face < ActiveRecord::Base
   belongs_to :man, inverse_of: :face
   belongs_to :polymorphic_man, polymorphic: true, inverse_of: :polymorphic_face
diff --git a/activerecord/test/models/family.rb b/activerecord/test/models/family.rb
index 5ae5a78c95..24bc3cc457 100644
--- a/activerecord/test/models/family.rb
+++ b/activerecord/test/models/family.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Family < ActiveRecord::Base
   has_many :family_trees, -> { where(token: nil) }
   has_many :members, through: :family_trees
diff --git a/activerecord/test/models/family_tree.rb b/activerecord/test/models/family_tree.rb
index cd9829fedd..94a905246a 100644
--- a/activerecord/test/models/family_tree.rb
+++ b/activerecord/test/models/family_tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class FamilyTree < ActiveRecord::Base
   belongs_to :member, class_name: "User", foreign_key: "member_id"
   belongs_to :family
diff --git a/activerecord/test/models/friendship.rb b/activerecord/test/models/friendship.rb
index 578382b494..e9ecfe7e25 100644
--- a/activerecord/test/models/friendship.rb
+++ b/activerecord/test/models/friendship.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Friendship < ActiveRecord::Base
   belongs_to :friend, class_name: "Person"
   # friend_too exists to test a bug, and probably shouldn't be used elsewhere
diff --git a/activerecord/test/models/guid.rb b/activerecord/test/models/guid.rb
index 05653ba498..8653b617b1 100644
--- a/activerecord/test/models/guid.rb
+++ b/activerecord/test/models/guid.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Guid < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/guitar.rb b/activerecord/test/models/guitar.rb
index cd068ff53d..a1a3226272 100644
--- a/activerecord/test/models/guitar.rb
+++ b/activerecord/test/models/guitar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Guitar < ActiveRecord::Base
   has_many :tuning_pegs, index_errors: true
   accepts_nested_attributes_for :tuning_pegs
diff --git a/activerecord/test/models/hotel.rb b/activerecord/test/models/hotel.rb
index 7bc717c891..1d20d17e3b 100644
--- a/activerecord/test/models/hotel.rb
+++ b/activerecord/test/models/hotel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Hotel < ActiveRecord::Base
   has_many :departments
   has_many :chefs, through: :departments
diff --git a/activerecord/test/models/image.rb b/activerecord/test/models/image.rb
index 7ae8e4a7f6..1efe679022 100644
--- a/activerecord/test/models/image.rb
+++ b/activerecord/test/models/image.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Image < ActiveRecord::Base
   belongs_to :imageable, foreign_key: :imageable_identifier, foreign_type: :imageable_class
 end
diff --git a/activerecord/test/models/interest.rb b/activerecord/test/models/interest.rb
index ec79416ee7..10e855be4d 100644
--- a/activerecord/test/models/interest.rb
+++ b/activerecord/test/models/interest.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Interest < ActiveRecord::Base
   belongs_to :man, inverse_of: :interests
   belongs_to :polymorphic_man, polymorphic: true, inverse_of: :polymorphic_interests
diff --git a/activerecord/test/models/invoice.rb b/activerecord/test/models/invoice.rb
index 4be5a00193..df37e2a9e1 100644
--- a/activerecord/test/models/invoice.rb
+++ b/activerecord/test/models/invoice.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Invoice < ActiveRecord::Base
   has_many :line_items, autosave: true
   before_save { |record| record.balance = record.line_items.map(&:amount).sum }
diff --git a/activerecord/test/models/item.rb b/activerecord/test/models/item.rb
index 336fb1769a..86a1fc625e 100644
--- a/activerecord/test/models/item.rb
+++ b/activerecord/test/models/item.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class AbstractItem < ActiveRecord::Base
   self.abstract_class = true
   has_one :tagging, as: :taggable
diff --git a/activerecord/test/models/job.rb b/activerecord/test/models/job.rb
index bbaef2792c..6c4dff4bcd 100644
--- a/activerecord/test/models/job.rb
+++ b/activerecord/test/models/job.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Job < ActiveRecord::Base
   has_many :references
   has_many :people, through: :references
diff --git a/activerecord/test/models/joke.rb b/activerecord/test/models/joke.rb
index eeb5818a1f..5c2443036a 100644
--- a/activerecord/test/models/joke.rb
+++ b/activerecord/test/models/joke.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Joke < ActiveRecord::Base
   self.table_name = "funny_jokes"
 end
diff --git a/activerecord/test/models/keyboard.rb b/activerecord/test/models/keyboard.rb
index bcede53ec9..d179de8e1c 100644
--- a/activerecord/test/models/keyboard.rb
+++ b/activerecord/test/models/keyboard.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Keyboard < ActiveRecord::Base
   self.primary_key = "key_number"
 end
diff --git a/activerecord/test/models/legacy_thing.rb b/activerecord/test/models/legacy_thing.rb
index eead181a0e..948d575bb8 100644
--- a/activerecord/test/models/legacy_thing.rb
+++ b/activerecord/test/models/legacy_thing.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class LegacyThing < ActiveRecord::Base
   self.locking_column = :version
 end
diff --git a/activerecord/test/models/lesson.rb b/activerecord/test/models/lesson.rb
index 4c88153068..086ff55b42 100644
--- a/activerecord/test/models/lesson.rb
+++ b/activerecord/test/models/lesson.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class LessonError < Exception
 end
 
diff --git a/activerecord/test/models/line_item.rb b/activerecord/test/models/line_item.rb
index 93f7cceb13..1ef2eda97a 100644
--- a/activerecord/test/models/line_item.rb
+++ b/activerecord/test/models/line_item.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class LineItem < ActiveRecord::Base
   belongs_to :invoice, touch: true
 end
diff --git a/activerecord/test/models/liquid.rb b/activerecord/test/models/liquid.rb
index 69d4d7df1a..9440292c78 100644
--- a/activerecord/test/models/liquid.rb
+++ b/activerecord/test/models/liquid.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Liquid < ActiveRecord::Base
   self.table_name = :liquid
   has_many :molecules, -> { distinct }
diff --git a/activerecord/test/models/man.rb b/activerecord/test/models/man.rb
index d2436a735c..bf81aa9fc6 100644
--- a/activerecord/test/models/man.rb
+++ b/activerecord/test/models/man.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Man < ActiveRecord::Base
   has_one :face, inverse_of: :man
   has_one :polymorphic_face, class_name: "Face", as: :polymorphic_man, inverse_of: :polymorphic_man
diff --git a/activerecord/test/models/matey.rb b/activerecord/test/models/matey.rb
index 80ee5f47c5..00311f78fe 100644
--- a/activerecord/test/models/matey.rb
+++ b/activerecord/test/models/matey.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Matey < ActiveRecord::Base
   belongs_to :pirate
   belongs_to :target, class_name: "Pirate"
diff --git a/activerecord/test/models/member.rb b/activerecord/test/models/member.rb
index 36f2461b84..99a037e0f6 100644
--- a/activerecord/test/models/member.rb
+++ b/activerecord/test/models/member.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Member < ActiveRecord::Base
   has_one :current_membership
   has_one :selected_membership
diff --git a/activerecord/test/models/member_detail.rb b/activerecord/test/models/member_detail.rb
index 157130986c..8311d202da 100644
--- a/activerecord/test/models/member_detail.rb
+++ b/activerecord/test/models/member_detail.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class MemberDetail < ActiveRecord::Base
   belongs_to :member, inverse_of: false
   belongs_to :organization
diff --git a/activerecord/test/models/member_type.rb b/activerecord/test/models/member_type.rb
index a13561c72a..3c159a885a 100644
--- a/activerecord/test/models/member_type.rb
+++ b/activerecord/test/models/member_type.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class MemberType < ActiveRecord::Base
   has_many :members
 end
diff --git a/activerecord/test/models/membership.rb b/activerecord/test/models/membership.rb
index 0f8be0ad85..bd957f1de8 100644
--- a/activerecord/test/models/membership.rb
+++ b/activerecord/test/models/membership.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Membership < ActiveRecord::Base
   enum type: %i(Membership CurrentMembership SuperMembership SelectedMembership TenantMembership)
   belongs_to :member
diff --git a/activerecord/test/models/mentor.rb b/activerecord/test/models/mentor.rb
index 66504b4e91..9e52d39e46 100644
--- a/activerecord/test/models/mentor.rb
+++ b/activerecord/test/models/mentor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Mentor < ActiveRecord::Base
   has_many :developers
 end
diff --git a/activerecord/test/models/minimalistic.rb b/activerecord/test/models/minimalistic.rb
index 2e3f8e081a..c31eea65c9 100644
--- a/activerecord/test/models/minimalistic.rb
+++ b/activerecord/test/models/minimalistic.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Minimalistic < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/minivan.rb b/activerecord/test/models/minivan.rb
index e9b05dadf2..4d04d808a9 100644
--- a/activerecord/test/models/minivan.rb
+++ b/activerecord/test/models/minivan.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Minivan < ActiveRecord::Base
   self.primary_key = :minivan_id
 
diff --git a/activerecord/test/models/mixed_case_monkey.rb b/activerecord/test/models/mixed_case_monkey.rb
index 1c35006665..552de2c18c 100644
--- a/activerecord/test/models/mixed_case_monkey.rb
+++ b/activerecord/test/models/mixed_case_monkey.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class MixedCaseMonkey < ActiveRecord::Base
   belongs_to :man
 end
diff --git a/activerecord/test/models/mocktail_designer.rb b/activerecord/test/models/mocktail_designer.rb
index 77b44651a3..fc9fc4c942 100644
--- a/activerecord/test/models/mocktail_designer.rb
+++ b/activerecord/test/models/mocktail_designer.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class MocktailDesigner < DrinkDesigner
 end
diff --git a/activerecord/test/models/molecule.rb b/activerecord/test/models/molecule.rb
index 26870c8f88..8e0f6eb6ee 100644
--- a/activerecord/test/models/molecule.rb
+++ b/activerecord/test/models/molecule.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Molecule < ActiveRecord::Base
   belongs_to :liquid
   has_many :electrons
diff --git a/activerecord/test/models/movie.rb b/activerecord/test/models/movie.rb
index 0302abad1e..fc620656e4 100644
--- a/activerecord/test/models/movie.rb
+++ b/activerecord/test/models/movie.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Movie < ActiveRecord::Base
   self.primary_key = "movieid"
 
diff --git a/activerecord/test/models/node.rb b/activerecord/test/models/node.rb
index 459ea8cf95..3422a9ea3a 100644
--- a/activerecord/test/models/node.rb
+++ b/activerecord/test/models/node.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Node < ActiveRecord::Base
   belongs_to :tree, touch: true
   belongs_to :parent,   class_name: "Node", touch: true, optional: true
diff --git a/activerecord/test/models/non_primary_key.rb b/activerecord/test/models/non_primary_key.rb
index 1cafb09608..4a5fdb88b8 100644
--- a/activerecord/test/models/non_primary_key.rb
+++ b/activerecord/test/models/non_primary_key.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class NonPrimaryKey < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/notification.rb b/activerecord/test/models/notification.rb
index 82edc64b68..9e8ce108d5 100644
--- a/activerecord/test/models/notification.rb
+++ b/activerecord/test/models/notification.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Notification < ActiveRecord::Base
   validates_presence_of :message
 end
diff --git a/activerecord/test/models/numeric_data.rb b/activerecord/test/models/numeric_data.rb
index c6e025a9ce..8998495101 100644
--- a/activerecord/test/models/numeric_data.rb
+++ b/activerecord/test/models/numeric_data.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class NumericData < ActiveRecord::Base
   self.table_name = "numeric_data"
   # Decimal columns with 0 scale being automatically treated as integers
diff --git a/activerecord/test/models/order.rb b/activerecord/test/models/order.rb
index 699be53959..c8693586a0 100644
--- a/activerecord/test/models/order.rb
+++ b/activerecord/test/models/order.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Order < ActiveRecord::Base
   belongs_to :billing, class_name: "Customer", foreign_key: "billing_customer_id"
   belongs_to :shipping, class_name: "Customer", foreign_key: "shipping_customer_id"
diff --git a/activerecord/test/models/organization.rb b/activerecord/test/models/organization.rb
index 462830dadc..c08a01994b 100644
--- a/activerecord/test/models/organization.rb
+++ b/activerecord/test/models/organization.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Organization < ActiveRecord::Base
   has_many :member_details
   has_many :members, through: :member_details
diff --git a/activerecord/test/models/other_dog.rb b/activerecord/test/models/other_dog.rb
index 418caf34be..a836d9de1a 100644
--- a/activerecord/test/models/other_dog.rb
+++ b/activerecord/test/models/other_dog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require_dependency "models/arunit2_model"
 
 class OtherDog < ARUnit2Model
diff --git a/activerecord/test/models/owner.rb b/activerecord/test/models/owner.rb
index 21fc9b6eb8..f6190fe5af 100644
--- a/activerecord/test/models/owner.rb
+++ b/activerecord/test/models/owner.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Owner < ActiveRecord::Base
   self.primary_key = :owner_id
   has_many :pets, -> { order "pets.name desc" }
diff --git a/activerecord/test/models/parrot.rb b/activerecord/test/models/parrot.rb
index 1e5f9285a8..4a027fa0bb 100644
--- a/activerecord/test/models/parrot.rb
+++ b/activerecord/test/models/parrot.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Parrot < ActiveRecord::Base
   self.inheritance_column = :parrot_sti_class
 
diff --git a/activerecord/test/models/person.rb b/activerecord/test/models/person.rb
index 18994d6f18..c1ea965a6e 100644
--- a/activerecord/test/models/person.rb
+++ b/activerecord/test/models/person.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Person < ActiveRecord::Base
   has_many :readers
   has_many :secure_readers
diff --git a/activerecord/test/models/personal_legacy_thing.rb b/activerecord/test/models/personal_legacy_thing.rb
index adde7a504a..1a70aa7e7b 100644
--- a/activerecord/test/models/personal_legacy_thing.rb
+++ b/activerecord/test/models/personal_legacy_thing.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PersonalLegacyThing < ActiveRecord::Base
   self.locking_column = :version
   belongs_to :person, counter_cache: true
diff --git a/activerecord/test/models/pet.rb b/activerecord/test/models/pet.rb
index 51a3e42815..f0d82ddfc9 100644
--- a/activerecord/test/models/pet.rb
+++ b/activerecord/test/models/pet.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Pet < ActiveRecord::Base
   attr_accessor :current_user
 
diff --git a/activerecord/test/models/pet_treasure.rb b/activerecord/test/models/pet_treasure.rb
index 1fe7807ffe..2d552bf50c 100644
--- a/activerecord/test/models/pet_treasure.rb
+++ b/activerecord/test/models/pet_treasure.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PetTreasure < ActiveRecord::Base
   self.table_name = "pets_treasures"
 
diff --git a/activerecord/test/models/pirate.rb b/activerecord/test/models/pirate.rb
index c532ab426e..21fe1b7847 100644
--- a/activerecord/test/models/pirate.rb
+++ b/activerecord/test/models/pirate.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Pirate < ActiveRecord::Base
   belongs_to :parrot, validate: true
   belongs_to :non_validated_parrot, class_name: "Parrot"
diff --git a/activerecord/test/models/possession.rb b/activerecord/test/models/possession.rb
index 0226336c16..d8c2a5f21f 100644
--- a/activerecord/test/models/possession.rb
+++ b/activerecord/test/models/possession.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Possession < ActiveRecord::Base
   self.table_name = "having"
 end
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index ed64e0ee52..534ba47c98 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Post < ActiveRecord::Base
   class CategoryPost < ActiveRecord::Base
     self.table_name = "categories_posts"
diff --git a/activerecord/test/models/price_estimate.rb b/activerecord/test/models/price_estimate.rb
index ce086e40a3..abdff640c7 100644
--- a/activerecord/test/models/price_estimate.rb
+++ b/activerecord/test/models/price_estimate.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class PriceEstimate < ActiveRecord::Base
   belongs_to :estimate_of, polymorphic: true
   belongs_to :thing, polymorphic: true
diff --git a/activerecord/test/models/professor.rb b/activerecord/test/models/professor.rb
index 4dfb1a9602..6ec183bb07 100644
--- a/activerecord/test/models/professor.rb
+++ b/activerecord/test/models/professor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require_dependency "models/arunit2_model"
 
 class Professor < ARUnit2Model
diff --git a/activerecord/test/models/project.rb b/activerecord/test/models/project.rb
index 4fbd986e40..e30f1d729a 100644
--- a/activerecord/test/models/project.rb
+++ b/activerecord/test/models/project.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Project < ActiveRecord::Base
   belongs_to :mentor
   has_and_belongs_to_many :developers, -> { distinct.order "developers.name desc, developers.id desc" }
diff --git a/activerecord/test/models/publisher.rb b/activerecord/test/models/publisher.rb
index 0d4a7f9235..55cf0e42a5 100644
--- a/activerecord/test/models/publisher.rb
+++ b/activerecord/test/models/publisher.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 module Publisher
 end
diff --git a/activerecord/test/models/publisher/article.rb b/activerecord/test/models/publisher/article.rb
index d73a8eb936..43b88117e0 100644
--- a/activerecord/test/models/publisher/article.rb
+++ b/activerecord/test/models/publisher/article.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Publisher::Article < ActiveRecord::Base
   has_and_belongs_to_many :magazines
   has_and_belongs_to_many :tags
diff --git a/activerecord/test/models/publisher/magazine.rb b/activerecord/test/models/publisher/magazine.rb
index 82e1a14008..25e34aca99 100644
--- a/activerecord/test/models/publisher/magazine.rb
+++ b/activerecord/test/models/publisher/magazine.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Publisher::Magazine < ActiveRecord::Base
   has_and_belongs_to_many :articles
 end
diff --git a/activerecord/test/models/randomly_named_c1.rb b/activerecord/test/models/randomly_named_c1.rb
index d4be1e13b4..1cd2ca1bb8 100644
--- a/activerecord/test/models/randomly_named_c1.rb
+++ b/activerecord/test/models/randomly_named_c1.rb
@@ -1,3 +1,4 @@
-class ClassNameThatDoesNotFollowCONVENTIONS < ActiveRecord::Base
-  self.table_name = :randomly_named_table1
-end
+# frozen_string_literal: true
+class ClassNameThatDoesNotFollowCONVENTIONS < ActiveRecord::Base
+  self.table_name = :randomly_named_table1
+end
diff --git a/activerecord/test/models/rating.rb b/activerecord/test/models/rating.rb
index 7420821db0..753df20e8d 100644
--- a/activerecord/test/models/rating.rb
+++ b/activerecord/test/models/rating.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Rating < ActiveRecord::Base
   belongs_to :comment
   has_many :taggings, as: :taggable
diff --git a/activerecord/test/models/reader.rb b/activerecord/test/models/reader.rb
index 7c5a159fe0..05a17eca8b 100644
--- a/activerecord/test/models/reader.rb
+++ b/activerecord/test/models/reader.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Reader < ActiveRecord::Base
   belongs_to :post
   belongs_to :person, inverse_of: :readers
diff --git a/activerecord/test/models/recipe.rb b/activerecord/test/models/recipe.rb
index c387230603..8f81807340 100644
--- a/activerecord/test/models/recipe.rb
+++ b/activerecord/test/models/recipe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Recipe < ActiveRecord::Base
   belongs_to :chef
 end
diff --git a/activerecord/test/models/record.rb b/activerecord/test/models/record.rb
index f77ac9fc03..81d5baa6b1 100644
--- a/activerecord/test/models/record.rb
+++ b/activerecord/test/models/record.rb
@@ -1,2 +1,3 @@
+# frozen_string_literal: true
 class Record < ActiveRecord::Base
 end
diff --git a/activerecord/test/models/reference.rb b/activerecord/test/models/reference.rb
index e2bb980fed..5daa48d8ce 100644
--- a/activerecord/test/models/reference.rb
+++ b/activerecord/test/models/reference.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Reference < ActiveRecord::Base
   belongs_to :person
   belongs_to :job
diff --git a/activerecord/test/models/reply.rb b/activerecord/test/models/reply.rb
index a2d169292a..f3372e81fd 100644
--- a/activerecord/test/models/reply.rb
+++ b/activerecord/test/models/reply.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "models/topic"
 
 class Reply < Topic
diff --git a/activerecord/test/models/ship.rb b/activerecord/test/models/ship.rb
index 77a7b22315..0ee8da78db 100644
--- a/activerecord/test/models/ship.rb
+++ b/activerecord/test/models/ship.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Ship < ActiveRecord::Base
   self.record_timestamps = false
 
diff --git a/activerecord/test/models/ship_part.rb b/activerecord/test/models/ship_part.rb
index 1a633b8d77..67c089a7d0 100644
--- a/activerecord/test/models/ship_part.rb
+++ b/activerecord/test/models/ship_part.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ShipPart < ActiveRecord::Base
   belongs_to :ship
   has_many :trinkets, class_name: "Treasure", as: :looter
diff --git a/activerecord/test/models/shop.rb b/activerecord/test/models/shop.rb
index f9d23d13b0..819af853ad 100644
--- a/activerecord/test/models/shop.rb
+++ b/activerecord/test/models/shop.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Shop
   class Collection < ActiveRecord::Base
     has_many :products, dependent: :nullify
diff --git a/activerecord/test/models/shop_account.rb b/activerecord/test/models/shop_account.rb
index 1580e8b20c..cb00e202f0 100644
--- a/activerecord/test/models/shop_account.rb
+++ b/activerecord/test/models/shop_account.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class ShopAccount < ActiveRecord::Base
   belongs_to :customer
   belongs_to :customer_carrier
diff --git a/activerecord/test/models/speedometer.rb b/activerecord/test/models/speedometer.rb
index 497c3aba9a..b34e3c16fc 100644
--- a/activerecord/test/models/speedometer.rb
+++ b/activerecord/test/models/speedometer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Speedometer < ActiveRecord::Base
   self.primary_key = :speedometer_id
   belongs_to :dashboard
diff --git a/activerecord/test/models/sponsor.rb b/activerecord/test/models/sponsor.rb
index 3f142b25fe..cfcd1f762a 100644
--- a/activerecord/test/models/sponsor.rb
+++ b/activerecord/test/models/sponsor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Sponsor < ActiveRecord::Base
   belongs_to :sponsor_club, class_name: "Club", foreign_key: "club_id"
   belongs_to :sponsorable, polymorphic: true
diff --git a/activerecord/test/models/string_key_object.rb b/activerecord/test/models/string_key_object.rb
index f084ec1bdc..94c7fb7582 100644
--- a/activerecord/test/models/string_key_object.rb
+++ b/activerecord/test/models/string_key_object.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class StringKeyObject < ActiveRecord::Base
   self.primary_key = :id
 end
diff --git a/activerecord/test/models/student.rb b/activerecord/test/models/student.rb
index 28a0b6c99b..888a0ae481 100644
--- a/activerecord/test/models/student.rb
+++ b/activerecord/test/models/student.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Student < ActiveRecord::Base
   has_and_belongs_to_many :lessons
   belongs_to :college
diff --git a/activerecord/test/models/subscriber.rb b/activerecord/test/models/subscriber.rb
index a820329003..8ef679486d 100644
--- a/activerecord/test/models/subscriber.rb
+++ b/activerecord/test/models/subscriber.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Subscriber < ActiveRecord::Base
   self.primary_key = "nick"
   has_many :subscriptions
diff --git a/activerecord/test/models/subscription.rb b/activerecord/test/models/subscription.rb
index 1cedf6deae..e210836413 100644
--- a/activerecord/test/models/subscription.rb
+++ b/activerecord/test/models/subscription.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Subscription < ActiveRecord::Base
   belongs_to :subscriber, counter_cache: :books_count
   belongs_to :book
diff --git a/activerecord/test/models/tag.rb b/activerecord/test/models/tag.rb
index c907aea10f..6c59dc6183 100644
--- a/activerecord/test/models/tag.rb
+++ b/activerecord/test/models/tag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Tag < ActiveRecord::Base
   has_many :taggings
   has_many :taggables, through: :taggings
diff --git a/activerecord/test/models/tagging.rb b/activerecord/test/models/tagging.rb
index f739b4a197..0060b96f73 100644
--- a/activerecord/test/models/tagging.rb
+++ b/activerecord/test/models/tagging.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # test that attr_readonly isn't called on the :taggable polymorphic association
 module Taggable
 end
diff --git a/activerecord/test/models/task.rb b/activerecord/test/models/task.rb
index e36989dd56..1ab1048bdb 100644
--- a/activerecord/test/models/task.rb
+++ b/activerecord/test/models/task.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Task < ActiveRecord::Base
   def updated_at
     ending
diff --git a/activerecord/test/models/topic.rb b/activerecord/test/models/topic.rb
index d9381ac9cf..a74263428b 100644
--- a/activerecord/test/models/topic.rb
+++ b/activerecord/test/models/topic.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Topic < ActiveRecord::Base
   scope :base, -> { all }
   scope :written_before, lambda { |time|
diff --git a/activerecord/test/models/toy.rb b/activerecord/test/models/toy.rb
index ddc7048a56..97b877caea 100644
--- a/activerecord/test/models/toy.rb
+++ b/activerecord/test/models/toy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Toy < ActiveRecord::Base
   self.primary_key = :toy_id
   belongs_to :pet
diff --git a/activerecord/test/models/traffic_light.rb b/activerecord/test/models/traffic_light.rb
index a6b7edb882..595b1cb716 100644
--- a/activerecord/test/models/traffic_light.rb
+++ b/activerecord/test/models/traffic_light.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class TrafficLight < ActiveRecord::Base
   serialize :state, Array
   serialize :long_state, Array
diff --git a/activerecord/test/models/treasure.rb b/activerecord/test/models/treasure.rb
index fb2a5d44e2..3f2162a63d 100644
--- a/activerecord/test/models/treasure.rb
+++ b/activerecord/test/models/treasure.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Treasure < ActiveRecord::Base
   has_and_belongs_to_many :parrots
   belongs_to :looter, polymorphic: true
diff --git a/activerecord/test/models/treaty.rb b/activerecord/test/models/treaty.rb
index 373cd48f71..a6c227c84e 100644
--- a/activerecord/test/models/treaty.rb
+++ b/activerecord/test/models/treaty.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Treaty < ActiveRecord::Base
   self.primary_key = :treaty_id
 
diff --git a/activerecord/test/models/tree.rb b/activerecord/test/models/tree.rb
index dc29cccc9c..844c2693ec 100644
--- a/activerecord/test/models/tree.rb
+++ b/activerecord/test/models/tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Tree < ActiveRecord::Base
   has_many :nodes, dependent: :destroy
 end
diff --git a/activerecord/test/models/tuning_peg.rb b/activerecord/test/models/tuning_peg.rb
index 1252d6dc1d..4fee61c565 100644
--- a/activerecord/test/models/tuning_peg.rb
+++ b/activerecord/test/models/tuning_peg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class TuningPeg < ActiveRecord::Base
   belongs_to :guitar
   validates_numericality_of :pitch
diff --git a/activerecord/test/models/tyre.rb b/activerecord/test/models/tyre.rb
index e50a21ca68..03ba9d3364 100644
--- a/activerecord/test/models/tyre.rb
+++ b/activerecord/test/models/tyre.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Tyre < ActiveRecord::Base
   belongs_to :car
 
diff --git a/activerecord/test/models/user.rb b/activerecord/test/models/user.rb
index 5089a795f4..3ceacc5e7f 100644
--- a/activerecord/test/models/user.rb
+++ b/activerecord/test/models/user.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "models/job"
 
 class User < ActiveRecord::Base
diff --git a/activerecord/test/models/uuid_child.rb b/activerecord/test/models/uuid_child.rb
index a3d0962ad6..eaa380ba20 100644
--- a/activerecord/test/models/uuid_child.rb
+++ b/activerecord/test/models/uuid_child.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class UuidChild < ActiveRecord::Base
   belongs_to :uuid_parent
 end
diff --git a/activerecord/test/models/uuid_item.rb b/activerecord/test/models/uuid_item.rb
index 2353e40213..bb152c381a 100644
--- a/activerecord/test/models/uuid_item.rb
+++ b/activerecord/test/models/uuid_item.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class UuidItem < ActiveRecord::Base
 end
 
diff --git a/activerecord/test/models/uuid_parent.rb b/activerecord/test/models/uuid_parent.rb
index 5634f22d0c..f654a964e0 100644
--- a/activerecord/test/models/uuid_parent.rb
+++ b/activerecord/test/models/uuid_parent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class UuidParent < ActiveRecord::Base
   has_many :uuid_children
 end
diff --git a/activerecord/test/models/vegetables.rb b/activerecord/test/models/vegetables.rb
index a4590d06e0..c97b6b939d 100644
--- a/activerecord/test/models/vegetables.rb
+++ b/activerecord/test/models/vegetables.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Vegetable < ActiveRecord::Base
   validates_presence_of :name
 
diff --git a/activerecord/test/models/vehicle.rb b/activerecord/test/models/vehicle.rb
index 855bc4e325..61e18b2e40 100644
--- a/activerecord/test/models/vehicle.rb
+++ b/activerecord/test/models/vehicle.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Vehicle < ActiveRecord::Base
   self.abstract_class = true
   default_scope -> { where("tires_count IS NOT NULL") }
diff --git a/activerecord/test/models/vertex.rb b/activerecord/test/models/vertex.rb
index 3d19433b6f..b90f71cec6 100644
--- a/activerecord/test/models/vertex.rb
+++ b/activerecord/test/models/vertex.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # This class models a vertex in a directed graph.
 class Vertex < ActiveRecord::Base
   has_many :sink_edges, class_name: "Edge", foreign_key: "source_id"
diff --git a/activerecord/test/models/warehouse_thing.rb b/activerecord/test/models/warehouse_thing.rb
index f20bd1a245..684af49f2f 100644
--- a/activerecord/test/models/warehouse_thing.rb
+++ b/activerecord/test/models/warehouse_thing.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WarehouseThing < ActiveRecord::Base
   self.table_name = "warehouse-things"
 
diff --git a/activerecord/test/models/wheel.rb b/activerecord/test/models/wheel.rb
index cba2b3e518..f2fecf9545 100644
--- a/activerecord/test/models/wheel.rb
+++ b/activerecord/test/models/wheel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Wheel < ActiveRecord::Base
   belongs_to :wheelable, polymorphic: true, counter_cache: true
 end
diff --git a/activerecord/test/models/without_table.rb b/activerecord/test/models/without_table.rb
index 7c0fc286e1..77a471e682 100644
--- a/activerecord/test/models/without_table.rb
+++ b/activerecord/test/models/without_table.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class WithoutTable < ActiveRecord::Base
   default_scope -> { where(published: true) }
 end
diff --git a/activerecord/test/models/zine.rb b/activerecord/test/models/zine.rb
index 3f2b348b46..4c72cbb242 100644
--- a/activerecord/test/models/zine.rb
+++ b/activerecord/test/models/zine.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Zine < ActiveRecord::Base
   has_many :interests, inverse_of: :zine
 end
diff --git a/activerecord/test/schema/mysql2_specific_schema.rb b/activerecord/test/schema/mysql2_specific_schema.rb
index 90a314c83c..f55b030ebf 100644
--- a/activerecord/test/schema/mysql2_specific_schema.rb
+++ b/activerecord/test/schema/mysql2_specific_schema.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 ActiveRecord::Schema.define do
 
   if ActiveRecord::Base.connection.version >= "5.6.0"
diff --git a/activerecord/test/schema/oracle_specific_schema.rb b/activerecord/test/schema/oracle_specific_schema.rb
index 264d9b8910..9129981708 100644
--- a/activerecord/test/schema/oracle_specific_schema.rb
+++ b/activerecord/test/schema/oracle_specific_schema.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 ActiveRecord::Schema.define do
 
   execute "drop table test_oracle_defaults" rescue nil
diff --git a/activerecord/test/schema/postgresql_specific_schema.rb b/activerecord/test/schema/postgresql_specific_schema.rb
index e56e8fa36a..dbf0972b4b 100644
--- a/activerecord/test/schema/postgresql_specific_schema.rb
+++ b/activerecord/test/schema/postgresql_specific_schema.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 ActiveRecord::Schema.define do
 
   enable_extension!("uuid-ossp", ActiveRecord::Base.connection)
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index f534e9c00e..d4f029ff16 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 ActiveRecord::Schema.define do
   # ------------------------------------------------------------------- #
   #                                                                     #
diff --git a/activerecord/test/support/config.rb b/activerecord/test/support/config.rb
index aaff408b41..e385d7fff7 100644
--- a/activerecord/test/support/config.rb
+++ b/activerecord/test/support/config.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "yaml"
 require "erb"
 require "fileutils"
diff --git a/activerecord/test/support/connection.rb b/activerecord/test/support/connection.rb
index 1a609e13c3..06a037d3d0 100644
--- a/activerecord/test/support/connection.rb
+++ b/activerecord/test/support/connection.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "active_support/logger"
 require "models/college"
 require "models/course"
diff --git a/activerecord/test/support/connection_helper.rb b/activerecord/test/support/connection_helper.rb
index 4a19e5df44..5e37a4a991 100644
--- a/activerecord/test/support/connection_helper.rb
+++ b/activerecord/test/support/connection_helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module ConnectionHelper
   def run_without_connection
     original_connection = ActiveRecord::Base.remove_connection
diff --git a/activerecord/test/support/ddl_helper.rb b/activerecord/test/support/ddl_helper.rb
index 43cb235e01..3a07316637 100644
--- a/activerecord/test/support/ddl_helper.rb
+++ b/activerecord/test/support/ddl_helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module DdlHelper
   def with_example_table(connection, table_name, definition = nil)
     connection.execute("CREATE TABLE #{table_name}(#{definition})")
diff --git a/activerecord/test/support/schema_dumping_helper.rb b/activerecord/test/support/schema_dumping_helper.rb
index 666c1b6a14..1a3f67f3ed 100644
--- a/activerecord/test/support/schema_dumping_helper.rb
+++ b/activerecord/test/support/schema_dumping_helper.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module SchemaDumpingHelper
   def dump_table_schema(table, connection = ActiveRecord::Base.connection)
     old_ignore_tables = ActiveRecord::SchemaDumper.ignore_tables
author	Kir Shatrov <shatrov@me.com>	2017-06-22 22:59:18 -0400
committer	Kir Shatrov <shatrov@me.com>	2017-07-01 02:11:03 +0300
commit	cfade1ec7ee7b5b51f3c1578e3474f9c156f2971 (patch)
tree	5c12d112bf4d039587d712b0cae92a2d920fee23 /activerecord/test
parent	5fe2a4f929fff7fa725545c47ac0f9372d8c643d (diff)
download	rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.tar.gz rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.tar.bz2 rails-cfade1ec7ee7b5b51f3c1578e3474f9c156f2971.zip