Fix N+1 at notification (#5752)

app/models/notification.rb

@@ -24,7 +24,7 @@ class Notification < ApplicationRecord
     favourite:      'Favourite',
   }.freeze
 
-  STATUS_INCLUDES = [:account, :stream_entry, :media_attachments, :tags, mentions: :account, reblog: [:stream_entry, :account, :media_attachments, :tags, mentions: :account]].freeze
+  STATUS_INCLUDES = [:account, :application, :stream_entry, :media_attachments, :tags, mentions: :account, reblog: [:stream_entry, :account, :application, :media_attachments, :tags, mentions: :account]].freeze
 
   belongs_to :account
   belongs_to :from_account, class_name: 'Account'
@@ -55,9 +55,11 @@ class Notification < ApplicationRecord
   def target_status
     case type
     when :reblog
-      activity&.reblog
+      status&.reblog
-    when :favourite, :mention
+    when :favourite
-      activity&.status
+      favourite&.status
+    when :mention
+      mention&.status
     end
   end
 

spec/models/notification_spec.rb

@@ -6,23 +6,18 @@ RSpec.describe Notification, type: :model do
   end
 
   describe '#target_status' do
-    before do
+    let(:notification) { Fabricate(:notification, activity_type: type, activity: activity) }
-      allow(notification).to receive(:type).and_return(type)
+    let(:status)       { Fabricate(:status) }
-      allow(notification).to receive(:activity).and_return(activity)
+    let(:reblog)       { Fabricate(:status, reblog: status) }
-    end
+    let(:favourite)    { Fabricate(:favourite, status: status) }
-
+    let(:mention)      { Fabricate(:mention, status: status) }
-    let(:notification) { Fabricate(:notification) }
-    let(:status)       { instance_double('Status') }
-    let(:favourite)    { instance_double('Favourite') }
-    let(:mention)      { instance_double('Mention') }
 
     context 'type is :reblog' do
       let(:type)     { :reblog }
-      let(:activity) { status }
+      let(:activity) { reblog }
 
-      it 'calls activity.reblog' do
+      it 'returns status' do
-        expect(activity).to receive(:reblog)
+        expect(notification.target_status).to eq status
-        notification.target_status
       end
     end
 
@@ -30,9 +25,8 @@ RSpec.describe Notification, type: :model do
       let(:type)     { :favourite }
       let(:activity) { favourite }
 
-      it 'calls activity.status' do
+      it 'returns status' do
-        expect(activity).to receive(:status)
+        expect(notification.target_status).to eq status
-        notification.target_status
       end
     end
 
@@ -40,9 +34,8 @@ RSpec.describe Notification, type: :model do
       let(:type)     { :mention }
       let(:activity) { mention }
 
-      it 'calls activity.status' do
+      it 'returns status' do
-        expect(activity).to receive(:status)
+        expect(notification.target_status).to eq status
-        notification.target_status
       end
     end
   end