DRY up reblog vs original status check

Checking reblog vs original status was happening in multiple places
across the app. For views, this logic was encapsulated in a helper
method named `proper_status` but in the other layers of the app, the
logic was duplicated.

Because the logic is used at all layers of the app, we extracted it into
a `Status#proper` method on the model and changed all uses of the logic
to use this method. There is now a single source of truth for this
condition.

We added test coverage to untested methods that got refactored.

app/helpers/stream_entries_helper.rb

@@ -34,10 +34,6 @@ module StreamEntriesHelper
     user_signed_in? && @favourited.key?(status.id) ? 'favourited' : ''
   end
 
-  def proper_status(status)
-    status.reblog? ? status.reblog : status
-  end
-
   def rtl?(text)
     return false if text.empty?
 

app/lib/atom_serializer.rb

@@ -328,7 +328,7 @@ class AtomSerializer
 
   def serialize_status_attributes(entry, status)
     append_element(entry, 'summary', status.spoiler_text) unless status.spoiler_text.blank?
-    append_element(entry, 'content', Formatter.instance.format(status.reblog? ? status.reblog : status).to_str, type: 'html')
+    append_element(entry, 'content', Formatter.instance.format(status.proper).to_str, type: 'html')
 
     status.mentions.each do |mentioned|
       append_element(entry, 'link', nil, rel: :mentioned, 'ostatus:object-type': TagManager::TYPES[:person], href: TagManager.instance.uri_for(mentioned.account))

app/models/account.rb

@@ -125,11 +125,11 @@ class Account < ApplicationRecord
   end
 
   def favourited?(status)
-    (status.reblog? ? status.reblog : status).favourites.where(account: self).count.positive?
+    status.proper.favourites.where(account: self).count.positive?
   end
 
   def reblogged?(status)
-    (status.reblog? ? status.reblog : status).reblogs.where(account: self).count.positive?
+    status.proper.reblogs.where(account: self).count.positive?
   end
 
   def keypair

app/models/status.rb

@@ -62,8 +62,12 @@ class Status < ApplicationRecord
     reply? ? :comment : :note
   end
 
+  def proper
+    reblog? ? reblog : self
+  end
+
   def content
-    reblog? ? reblog.text : text
+    proper.text
   end
 
   def target

app/views/stream_entries/_status.html.haml

@@ -16,7 +16,7 @@
           %strong= display_name(status.account)
         = t('stream_entries.reblogged')
 
-  = render partial: centered ? 'stream_entries/detailed_status' : 'stream_entries/simple_status', locals: { status: proper_status(status) }
+  = render partial: centered ? 'stream_entries/detailed_status' : 'stream_entries/simple_status', locals: { status: status.proper }
 
 - if include_threads
   = render partial: 'stream_entries/status', collection: @descendants, as: :status, locals: { is_successor: true }