Prepare Mastodon for Rails 6 (#15911)

* Fix misuse of foreign_type

* Fix use of removed "add_template_helper"

* Use response.media_type instead of response.content_type in tests

* Fix CSV export controller test on Rails 6

Rails 6 sets a "filename*" field in the Content-Disposition header to
explicitly encode the filename as UTF-8.

This changes checks the first part of the Content-Disposition header so
it matches in both Rails 5 and Rails 6.

* Fix emoji formatting with Rails 6

* Make emoji output more idiomatic and robust

* Switch from redis-rails gem to built-in Rails redis cache storage

1 files changed, 6 insertions, 6 deletions

diff --git a/spec/controllers/activitypub/outboxes_controller_spec.rb b/spec/controllers/activitypub/outboxes_controller_spec.rb
index 84e3a8956..d23f2c17c 100644
--- a/spec/controllers/activitypub/outboxes_controller_spec.rb
+++ b/spec/controllers/activitypub/outboxes_controller_spec.rb
@@ -46,7 +46,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns totalItems' do
@@ -85,7 +85,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns orderedItems with public or unlisted statuses' do
@@ -133,7 +133,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns orderedItems with public or unlisted statuses' do
@@ -159,7 +159,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns orderedItems with private statuses' do
@@ -185,7 +185,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns empty orderedItems' do
@@ -210,7 +210,7 @@ RSpec.describe ActivityPub::OutboxesController, type: :controller do
         end
 
         it 'returns application/activity+json' do
-          expect(response.content_type).to eq 'application/activity+json'
+          expect(response.media_type).to eq 'application/activity+json'
         end
 
         it 'returns empty orderedItems' do