Clear screenshots files in `tmp:clear` task

If system test fails, it creates screenshot under `tmp/screenshots`.
https://github.com/rails/rails/blob/34fe2a4fc778d18b7fe6bdf3629c1481bee789b9/actionpack/lib/action_dispatch/system_testing/test_helpers/screenshot_helper.rb#L45

But currently, screenshot files is not cleared by `tmp:clear` task.
This patch make clears screenshot files with `tmp:clear` task as well
as other tmp files.

1 files changed, 36 insertions, 0 deletions

diff --git a/railties/test/application/rake/tmp_test.rb b/railties/test/application/rake/tmp_test.rb
new file mode 100644
index 0000000000..bc9865b0de
--- /dev/null
+++ b/railties/test/application/rake/tmp_test.rb
@@ -0,0 +1,36 @@
+require "isolation/abstract_unit"
+
+module ApplicationTests
+  module RakeTests
+    class TmpTest < ActiveSupport::TestCase
+      include ActiveSupport::Testing::Isolation
+
+      def setup
+        build_app
+      end
+
+      def teardown
+        teardown_app
+      end
+
+      test "tmp:clear clear cache, socket and screenshot files" do
+        Dir.chdir(app_path) do
+          FileUtils.mkdir_p("tmp/cache")
+          FileUtils.touch("tmp/cache/cache_file")
+
+          FileUtils.mkdir_p("tmp/sockets")
+          FileUtils.touch("tmp/sockets/socket_file")
+
+          FileUtils.mkdir_p("tmp/screenshots")
+          FileUtils.touch("tmp/screenshots/fail.png")
+
+          `rails tmp:clear`
+
+          assert_not File.exist?("tmp/cache/cache_file")
+          assert_not File.exist?("tmp/sockets/socket_file")
+          assert_not File.exist?("tmp/screenshots/fail.png")
+        end
+      end
+    end
+  end
+end