This adds a test for the `Feed#get` method. While the data
transformations in `Feed#get` may seem redundant, they are important to
maintain the order from Redis. The tests I wrote will fail if someone
tries to refactor away this "redundancy" (as I tried to do in the first
iteration of this change).

In #2110, a new attachment type "unknown" was introduced for
attachments that were rejected due to a domain being blocked using
reject_media. However, the "type" field was never set to "unknown"
because a default value of "0" (image) is set for that column,
causing the `type.blank?` expression to always equal false.

This version uses type_changed? instead, causing the type to be set
to "unknown" unless a type has been explicitly set. This introduces
a small change in behaviour causing the type to be set to unknown
before paperclip calls `before_post_process`. Presumably this
behaviour is more appropriate than the current one because the
attachment type has not been determined by that point.

Included are new tests for `ProcessFeedService` and
`UpdateRemoteProfileService` which now check that remote media is
downloaded for non-blocked domains and is rejected for others.

* Add render_views in more places

* Delegate methods from account to user with allow nil true, so that admin accounts show view renders when missing a user

* Use actual account instances in authorize follow controller spec

* Add rough outline of coverage needed for public timeline

* Specs for visibility, replies, boosts

* Specs for silenced account

* Specs for local_only option

* Specs for blocks and mutes

* Add tentative spec around including other silenced account statuses

* Add with_public_visibility scope

* Add simple coverage for tag_timeline

* Tag timeline includes replies

* Replace tag.statuses with a tagged_with scope in tag timeline method

* Use with_public_visibility in tag timeline

* Extract common scope between public and tag timelines to method

* Extract local domain check to local_only scope

* Extract local_only check to starting scope method

* Move list of excluded from timeline account ids to account model

* Simplify excluded accounts list on account model

* Only join accounts when needed

* Rename method for account specific filtering

* Extract method for account exclusions

* Fix bug where silenced accounts were not including statuses from other silenced accounts

* DRY up filter application from account or no account

* timeline_scope can be private

* Add spec showing that account can find its excluded accounts ids

* Add spec which fails if local_only does not have a left outer join

* rubocop

* Add coverage for remote_follow#new

* Fix reference to authorize_follows/card partial

* Instead of parsing shared status contents verbatim, make roundtrip
to purported original URL. Confirm that the "original" URL is from the
same domain as the author it claims to be from.

* Fix obvious typo, add comment

* Use URI look-up first

* Add test, update Goldfinger dependency to make less useless HTTP requests per Webfinger lookup

* OEmbed support for PreviewCard

* Improve ProviderDiscovery code failure treatment

* Do not crawl links if there is a content warning, since those
don't display a link card anyway

* Reset db schema

* Fresh migrate

* Fix rubocop style issues
Fix #1681 - return existing access token when applicable instead of creating new

* Fix test

* Extract http client to helper

* Improve oembed controller

* Add coverage for domain block service with silence

* Get rid of warning about find_each and order

* Move domain_block to attr_reader

* Move optional clear_media into silence_accounts method

* Use blocked_domain method to reduce passed vars

* Extract blocked_domain_accounts method to find accounts on the domain

* Extract media_from_blocked_domain method to find relevant attachments

* Separate destruction of account images and account attachments

* Fixes #1985

- add migration AddMediaAttachmentMeta, which add meta field to media_attachments
- before saving attachment, set file meta if needed
- add meta in api

* add spec

* align the “size” format for image and video

* fix code climate

* fixes media_attachment_spec.rb

* Stricter whitelist rules

* Linting

* Added spec for blacklisting

* Test subdomain blacklist on domain whitelist

* No need to split

* Change spec name

This PR fixes I18n.locale for rake middlewares. Mastodon uses Devise that depends on Warden.
Warden::Manager can be found in rake middleware. It is outside of the controller.

In the case of authentication failed, warden calls throw(:warden). At the time Warden::Manager
delegates request to failure_app to generate response and flash[:alert] after catching it.
Unfortunately, I18n.locale is already reset then because I18n.with_locale is enabled only
inside the controller. If we used I18n.locale=, Devise::FailureApp could get the current locale.

* Change ActivityPub paging to match spec. Clean up ActivityPub outbox changes.

* Fix code style and test failures for OutboxController.

* Attempt to fix CI errors.

duplicates. Web UI regenerates UUID for that header every time the compose
form is changed or successfully submitted

Also, fix Farsi i18n overwriting the English one

* Fix #2119 - Whenever about to send a HTTP request, normalize the URI

* Add test for IDN request in FetchLinkCardService

* Perform IDN normalization on domains before they are stored in the DB

Fix flashes partial render error for controllers which don't inherit from application controller (#2400)

* Add failing spec for oauth/authorized_applications controller

* Use explicit reference to flashes partial from admin layout

Because some of the controllers which use the admin layout do not inherit from
application controller, this partial is not in their view path.

* Make private toots get PuSHed to subscription URLs that belong to domains where you have approved followers

* Authorized followers controller, stub for bulk action

* Soft block in the background

* Add simple test for new controller

* Rename Settings::FollowersController to Settings::FollowerDomainsController, paginate results,
rename "private" post setting to "followers-only", fix pagination style, improve post privacy
preferences style, improve warning style

* Extract compose form warnings into own container, show warning when posting to followers-only with unlocked account

* Add failing spec showing that human_locales does not match what i18n knows about

* Add missing `ar` key for arabic to human locales

* Remove duplicate `id` key from available locales

* Sort keys in human locales list

* Add spec for human_locale helper

The two methods `StreamEntriesHelper#stream_link_target` and
`StreamEntriesHelper#acct` are based on checking whether we are running
in an embedded view.

This adds some test helper code to make the testing easier. We extracted
some "magic strings" to constants to lower the coupling in the specs.

The code that generates CSS is based on a lot of boolean conditions.
The possible combinations of these grows exponentially as we add more
conditions.

Since most of the code is conditional on a single boolean, we tested the
following:

1. All `false`
2. All `true`
3. Each individual flag set to `true`

The methods tested are:

* `StreamEntriesHelper#style_classes`
* `StreamEntriesHelper#microformats_classes`
* `StreamEntriesHelper#microformats_h_class`

ActivityPub: Add basic, read-only support for Outboxes, Notes, and Create/Announce Activities (#2197)

* Clean up collapsible components

* Expose user Outboxes and AS2 representations of statuses

* Save work thus far.

* Fix bad merge.

* Save my work

* Clean up pagination.

* First test working.

* Add tests.

* Add Forbidden error template.

* Revert yarn.lock changes.

* Fix code style deviations and use localized instead of hardcoded English text.

* Shows confirmed status in list.

* Adds ability to confirm users in admin UI.

* Added new english translations.

* Addresses feedback from #2245.

* More feedback.

* add og:url to stream_item view

* add og:url and text to about/show

* add og:url to profile, followers and follows pages

* Add html lang attributes around statuses

* Remove urls from language detection

* Add spec coverage for settings/two_factor_auth area

* extract setup method for qr code

* Move otp required check to before action

* Merge method only used once

* Remove duplicate view

* Consolidate creation of @codes for backup

* Move settings/2fq#recovery_codes to settings/recovery_codes#create

* Rename settings/two_factor_auth#disable to #destroy

* Add coverage for the otp required path on 2fa#show

* Clean up the recovery codes list styles

* Move settings/two_factor_auth to settings/two_factor_authentication

* Reorganize the settings two factor auth area

Updated to use a flow like:

- settings/two_factor_authentication goes to a #show view which has a button
  either enable or disable 2fa on the account
- the disable button turns off the otp requirement for the user
- the enable button cycles the user secret and redirects to a confirmation page
- the confirmation page is a #new view which shows the QR code for user
- that page posts to #create which verifies the code, and creates the recovery
  codes
- that create action shares a view with a recovery codes controller which can be
  used separately to reset codes if needed

We used some random Arabic characters to test that the various RTL
conditions got triggered.

* Add user spec for settings, highlight global default mutation issue

* Fix mutation issue caused by settings/preferences spec

* Add missing fields group on preferences page

* Clean up settings/preferences controller

* Extract a UserSettingsDecorator

* Add render_views for admin/settings spec

* Add coverage for admin/settings#update

* Add coverage for admin/settings typecasting open_registrations setting

* Simplify how admin/settings finds the value for updating

* Rely on activerecord to not update a value that hasnt changed

* Add coverage for non-existent setting

* Use a constant for boolean settings