Refactor and improve tests (#17386)

* Change account and user fabricators to simplify and improve tests

- `Fabricate(:account)` implicitly fabricates an associated `user` if
  no `domain` attribute is given (an account with `domain: nil` is
  considered a local account, but no user record was created), unless
  `user: nil` is passed
- `Fabricate(:account, user: Fabricate(:user))` should still be possible
  but is discouraged.

* Fix and refactor tests

- avoid passing unneeded attributes to `Fabricate(:user)` or
  `Fabricate(:account)`
- avoid embedding `Fabricate(:user)` into a `Fabricate(:account)` or the other
  way around
- prefer `Fabricate(:user, account_attributes: …)` to
  `Fabricate(:user, account: Fabricate(:account, …)`
- also, some tests were using remote accounts with local user records, which is
  not representative of production code.

spec/policies/account_moderation_note_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe AccountModerationNotePolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :create? do
     context 'staff' do
@@ -42,7 +42,7 @@ RSpec.describe AccountModerationNotePolicy do
     end
 
     context 'neither admin nor owner' do
-      let(:kevin) { Fabricate(:user).account }
+      let(:kevin) { Fabricate(:account) }
 
       it 'denies to destroy' do
         expect(subject).to_not permit(kevin, account_moderation_note)

spec/policies/account_policy_spec.rb

@@ -6,8 +6,8 @@ require 'pundit/rspec'
 RSpec.describe AccountPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
-  let(:alice)   { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
+  let(:alice)   { Fabricate(:account) }
 
   permissions :index? do
     context 'staff' do

spec/policies/backup_policy_spec.rb

@@ -5,7 +5,7 @@ require 'pundit/rspec'
 
 RSpec.describe BackupPolicy do
   let(:subject) { described_class }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :create? do
     context 'not user_signed_in?' do

spec/policies/custom_emoji_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe CustomEmojiPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index?, :enable?, :disable? do
     context 'staff' do

spec/policies/domain_block_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe DomainBlockPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index?, :show?, :create?, :destroy? do
     context 'admin' do

spec/policies/email_domain_block_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe EmailDomainBlockPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index?, :create?, :destroy? do
     context 'admin' do

spec/policies/instance_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe InstancePolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index?, :show?, :destroy? do
     context 'admin' do

spec/policies/invite_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe InvitePolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index? do
     context 'staff?' do

spec/policies/relay_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe RelayPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :update? do
     context 'admin?' do

spec/policies/report_note_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe ReportNotePolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :create? do
     context 'staff?' do

spec/policies/report_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe ReportPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :update?, :index?, :show? do
     context 'staff?' do

spec/policies/settings_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe SettingsPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :update?, :show? do
     context 'admin?' do

spec/policies/tag_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe TagPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :index?, :show?, :update? do
     context 'staff?' do

spec/policies/user_policy_spec.rb

@@ -6,7 +6,7 @@ require 'pundit/rspec'
 RSpec.describe UserPolicy do
   let(:subject) { described_class }
   let(:admin)   { Fabricate(:user, admin: true).account }
-  let(:john)    { Fabricate(:user).account }
+  let(:john)    { Fabricate(:account) }
 
   permissions :reset_password?, :change_email? do
     context 'staff?' do