1 files changed, 63 insertions, 0 deletions
diff --git a/railties/test/application/rake/dev_test.rb b/railties/test/application/rake/dev_test.rb
new file mode 100644
index 0000000000..a87f453075
--- /dev/null
+++ b/railties/test/application/rake/dev_test.rb
@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+require "isolation/abstract_unit"
+
+module ApplicationTests
+  module RakeTests
+    class RakeDevTest < ActiveSupport::TestCase
+      include ActiveSupport::Testing::Isolation
+
+      def setup
+        build_app
+        add_to_env_config("development", "config.active_support.deprecation = :stderr")
+      end
+
+      def teardown
+        teardown_app
+      end
+
+      test "dev:cache creates file and outputs message" do
+        Dir.chdir(app_path) do
+          stderr = capture(:stderr) do
+            output = run_rake_dev_cache
+            assert File.exist?("tmp/caching-dev.txt")
+            assert_match(/Development mode is now being cached/, output)
+          end
+          assert_match(/DEPRECATION WARNING: Using `bin\/rake dev:cache` is deprecated and will be removed in Rails 6.1/, stderr)
+        end
+      end
+
+      test "dev:cache deletes file and outputs message" do
+        Dir.chdir(app_path) do
+          stderr = capture(:stderr) do
+            run_rake_dev_cache # Create caching file.
+            output = run_rake_dev_cache # Delete caching file.
+            assert_not File.exist?("tmp/caching-dev.txt")
+            assert_match(/Development mode is no longer being cached/, output)
+          end
+          assert_match(/DEPRECATION WARNING: Using `bin\/rake dev:cache` is deprecated and will be removed in Rails 6.1/, stderr)
+        end
+      end
+
+      test "dev:cache touches tmp/restart.txt" do
+        Dir.chdir(app_path) do
+          stderr = capture(:stderr) do
+            run_rake_dev_cache
+            assert File.exist?("tmp/restart.txt")
+
+            prev_mtime = File.mtime("tmp/restart.txt")
+            run_rake_dev_cache
+            curr_mtime = File.mtime("tmp/restart.txt")
+            assert_not_equal prev_mtime, curr_mtime
+          end
+          assert_match(/DEPRECATION WARNING: Using `bin\/rake dev:cache` is deprecated and will be removed in Rails 6.1/, stderr)
+        end
+      end
+
+      private
+        def run_rake_dev_cache
+          `bin/rake dev:cache`
+        end
+    end
+  end
+end