Convert protected_environments to an array of strings

  These changes prevent ignoring environments name of which is a `Symbol`
  ```
  config.active_record.protected_environments = ['staging', :production]
  ```

1 files changed, 19 insertions, 2 deletions

diff --git a/activerecord/test/cases/tasks/database_tasks_test.rb b/activerecord/test/cases/tasks/database_tasks_test.rb
index 5a094ead42..fd381f229f 100644
--- a/activerecord/test/cases/tasks/database_tasks_test.rb
+++ b/activerecord/test/cases/tasks/database_tasks_test.rb
@@ -30,13 +30,30 @@ module ActiveRecord
     def test_raises_an_error_when_called_with_protected_environment
       ActiveRecord::Migrator.stubs(:current_version).returns(1)
 
-      protected_environments = ActiveRecord::Base.protected_environments.dup
+      protected_environments = ActiveRecord::Base.protected_environments
       current_env            = ActiveRecord::Migrator.current_environment
       assert_not_includes protected_environments, current_env
       # Assert no error
       ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
 
-      ActiveRecord::Base.protected_environments << current_env
+      ActiveRecord::Base.protected_environments = [current_env]
+      assert_raise(ActiveRecord::ProtectedEnvironmentError) do
+        ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
+      end
+    ensure
+      ActiveRecord::Base.protected_environments = protected_environments
+    end
+
+    def test_raises_an_error_when_called_with_protected_environment_which_name_is_a_symbol
+      ActiveRecord::Migrator.stubs(:current_version).returns(1)
+
+      protected_environments = ActiveRecord::Base.protected_environments
+      current_env            = ActiveRecord::Migrator.current_environment
+      assert_not_includes protected_environments, current_env
+      # Assert no error
+      ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
+
+      ActiveRecord::Base.protected_environments = [current_env.to_sym]
       assert_raise(ActiveRecord::ProtectedEnvironmentError) do
         ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
       end