4 files changed, 8 insertions, 0 deletions
diff --git a/railties/lib/rails/test_unit/line_filtering.rb b/railties/lib/rails/test_unit/line_filtering.rb
index 289afae331..e8b891d07b 100644
--- a/railties/lib/rails/test_unit/line_filtering.rb
+++ b/railties/lib/rails/test_unit/line_filtering.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "method_source"
 require "rails/test_unit/runner"
 
diff --git a/railties/lib/rails/test_unit/railtie.rb b/railties/lib/rails/test_unit/railtie.rb
index f1965f3b12..05f9a177d0 100644
--- a/railties/lib/rails/test_unit/railtie.rb
+++ b/railties/lib/rails/test_unit/railtie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "line_filtering"
 
 if defined?(Rake.application) && Rake.application.top_level_tasks.grep(/^(default$|test(:|$))/).any?
diff --git a/railties/lib/rails/test_unit/reporter.rb b/railties/lib/rails/test_unit/reporter.rb
index ab28034d27..7d3164f1eb 100644
--- a/railties/lib/rails/test_unit/reporter.rb
+++ b/railties/lib/rails/test_unit/reporter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_support/core_ext/class/attribute"
 require "minitest"
 
diff --git a/railties/lib/rails/test_unit/testing.rake b/railties/lib/rails/test_unit/testing.rake
index 97dd5cef10..18d699f806 100644
--- a/railties/lib/rails/test_unit/testing.rake
+++ b/railties/lib/rails/test_unit/testing.rake
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 gem "minitest"
 require "minitest"
 require_relative "runner"