Merge branch 'no-ivar-in-modules' into 'master'

Add cop to make sure we don't use ivar in a module

See merge request gitlab-org/gitlab-ce!12800

.rubocop.yml

@@ -1185,7 +1185,20 @@ RSpec/SubjectStub:
 RSpec/VerifiedDoubles:
   Enabled: false
 
-# GitlabSecurity ##############################################################
+# Gitlab ###################################################################
+
+Gitlab/ModuleWithInstanceVariables:
+  Enable: true
+  Exclude:
+    # We ignore Rails helpers right now because it's hard to workaround it
+    - app/helpers/**/*_helper.rb
+    # We ignore Rails mailers right now because it's hard to workaround it
+    - app/mailers/emails/**/*.rb
+    # We ignore spec helpers because it usually doesn't matter
+    - spec/support/**/*.rb
+    - features/steps/**/*.rb
+
+# GitlabSecurity ###########################################################
 
 GitlabSecurity/DeepMunge:
   Enabled: true

app/controllers/concerns/boards_responses.rb

@@ -24,11 +24,11 @@ def authorize_action_for!(resource, ability)
   end
 
   def respond_with_boards
-    respond_with(@boards)
+    respond_with(@boards) # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def respond_with_board
-    respond_with(@board)
+    respond_with(@board) # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def respond_with(resource)

app/controllers/concerns/creates_commit.rb

 module CreatesCommit
   extend ActiveSupport::Concern
+  include Gitlab::Utils::StrongMemoize
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def create_commit(service, success_path:, failure_path:, failure_view: nil, success_notice: nil)
     if can?(current_user, :push_code, @project)
       @project_to_commit_into = @project
@@ -45,6 +47,7 @@ def create_commit(service, success_path:, failure_path:, failure_view: nil, succ
       end
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def authorize_edit_tree!
     return if can_collaborate_with_project?
@@ -77,6 +80,7 @@ def final_success_path(success_path)
     end
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def new_merge_request_path
     project_new_merge_request_path(
       @project_to_commit_into,
@@ -88,20 +92,28 @@ def new_merge_request_path
       }
     )
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def existing_merge_request_path
-    project_merge_request_path(@project, @merge_request)
+    project_merge_request_path(@project, @merge_request) # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def merge_request_exists?
-    return @merge_request if defined?(@merge_request)
-
-    @merge_request = MergeRequestsFinder.new(current_user, project_id: @project.id).execute.opened
-      .find_by(source_project_id: @project_to_commit_into, source_branch: @branch_name, target_branch: @start_branch)
+    strong_memoize(:merge_request) do
+      MergeRequestsFinder.new(current_user, project_id: @project.id)
+        .execute
+        .opened
+        .find_by(
+          source_project_id: @project_to_commit_into,
+          source_branch: @branch_name,
+          target_branch: @start_branch)
+    end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def different_project?
-    @project_to_commit_into != @project
+    @project_to_commit_into != @project # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def create_merge_request?
@@ -109,6 +121,6 @@ def create_merge_request?
     # as the target branch in the same project,
     # we don't want to create a merge request.
     params[:create_merge_request].present? &&
-      (different_project? || @start_branch != @branch_name)
+      (different_project? || @start_branch != @branch_name) # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 end

app/controllers/concerns/group_tree.rb

 module GroupTree
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def render_group_tree(groups)
     @groups = if params[:filter].present?
                 Gitlab::GroupHierarchy.new(groups.search(params[:filter]))
@@ -20,5 +21,6 @@ def render_group_tree(groups)
         render json: serializer.represent(@groups)
       end
     end
+    # rubocop:enable Gitlab/ModuleWithInstanceVariables
   end
 end

app/controllers/concerns/issuable_actions.rb

@@ -17,7 +17,7 @@ def show
   end
 
   def update
-    @issuable = update_service.execute(issuable)
+    @issuable = update_service.execute(issuable) # rubocop:disable Gitlab/ModuleWithInstanceVariables
 
     respond_to do |format|
       format.html do
@@ -81,7 +81,7 @@ def bulk_update
   private
 
   def recaptcha_check_if_spammable(should_redirect = true, &block)
-    return yield unless @issuable.is_a? Spammable
+    return yield unless issuable.is_a? Spammable
 
     recaptcha_check_with_fallback(should_redirect, &block)
   end
@@ -89,7 +89,7 @@ def recaptcha_check_if_spammable(should_redirect = true, &block)
   def render_conflict_response
     respond_to do |format|
       format.html do
-        @conflict = true
+        @conflict = true # rubocop:disable Gitlab/ModuleWithInstanceVariables
         render :edit
       end
 
@@ -104,7 +104,7 @@ def render_conflict_response
   end
 
   def labels
-    @labels ||= LabelsFinder.new(current_user, project_id: @project.id).execute
+    @labels ||= LabelsFinder.new(current_user, project_id: @project.id).execute # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def authorize_destroy_issuable!
@@ -114,7 +114,7 @@ def authorize_destroy_issuable!
   end
 
   def authorize_admin_issuable!
-    unless can?(current_user, :"admin_#{resource_name}", @project)
+    unless can?(current_user, :"admin_#{resource_name}", @project) # rubocop:disable Gitlab/ModuleWithInstanceVariables
       return access_denied!
     end
   end
@@ -148,6 +148,7 @@ def resource_name
     @resource_name ||= controller_name.singularize
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def render_entity_json
     if @issuable.valid?
       render json: serializer.represent(@issuable)
@@ -155,6 +156,7 @@ def render_entity_json
       render json: { errors: @issuable.errors.full_messages }, status: :unprocessable_entity
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def serializer
     raise NotImplementedError
@@ -165,6 +167,6 @@ def update_service
   end
 
   def parent
-    @project || @group
+    @project || @group # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 end

app/controllers/concerns/issuable_collections.rb

@@ -2,6 +2,7 @@ module IssuableCollections
   extend ActiveSupport::Concern
   include SortingHelper
   include Gitlab::IssuableMetadata
+  include Gitlab::Utils::StrongMemoize
 
   included do
     helper_method :finder
@@ -9,6 +10,7 @@ module IssuableCollections
 
   private
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def set_issuables_index
     @issuables          = issuables_collection
     @issuables          = @issuables.page(params[:page])
@@ -33,6 +35,7 @@ def set_issuables_index
       @users.push(author) if author
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def issuables_collection
     finder.execute.preload(preload_for_collection)
@@ -41,7 +44,7 @@ def issuables_collection
   def redirect_out_of_range(total_pages)
     return false if total_pages.zero?
 
-    out_of_range = @issuables.current_page > total_pages
+    out_of_range = @issuables.current_page > total_pages # rubocop:disable Gitlab/ModuleWithInstanceVariables
 
     if out_of_range
       redirect_to(url_for(params.merge(page: total_pages, only_path: true)))
@@ -51,7 +54,7 @@ def redirect_out_of_range(total_pages)
   end
 
   def issuable_page_count
-    page_count_for_relation(@issuables, finder.row_count)
+    page_count_for_relation(@issuables, finder.row_count) # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def page_count_for_relation(relation, row_count)
@@ -66,6 +69,7 @@ def issuable_finder_for(finder_class)
     finder_class.new(current_user, filter_params)
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def filter_params
     set_sort_order_from_cookie
     set_default_state
@@ -90,6 +94,7 @@ def filter_params
 
     @filter_params.permit(IssuableFinder::VALID_PARAMS)
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def set_default_state
     params[:state] = 'opened' if params[:state].blank?
@@ -129,9 +134,9 @@ def update_cookie_value(value)
   end
 
   def finder
-    return @finder if defined?(@finder)
-
-    @finder = issuable_finder_for(@finder_type)
+    strong_memoize(:finder) do
+      issuable_finder_for(@finder_type) # rubocop:disable Gitlab/ModuleWithInstanceVariables
+    end
   end
 
   def collection_type

app/controllers/concerns/issues_action.rb

@@ -2,6 +2,7 @@ module IssuesAction
   extend ActiveSupport::Concern
   include IssuableCollections
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def issues
     @finder_type = IssuesFinder
     @label = finder.labels.first
@@ -17,4 +18,5 @@ def issues
       format.atom { render layout: 'xml.atom' }
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 end

app/controllers/concerns/merge_requests_action.rb

@@ -2,6 +2,7 @@ module MergeRequestsAction
   extend ActiveSupport::Concern
   include IssuableCollections
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def merge_requests
     @finder_type = MergeRequestsFinder
     @label = finder.labels.first
@@ -10,6 +11,7 @@ def merge_requests
 
     @issuable_meta_data = issuable_meta_data(@merge_requests, collection_type)
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   private
 

app/controllers/concerns/milestone_actions.rb

@@ -6,7 +6,7 @@ def merge_requests
       format.html { redirect_to milestone_redirect_path }
       format.json do
         render json: tabs_json("shared/milestones/_merge_requests_tab", {
-          merge_requests: @milestone.sorted_merge_requests,
+          merge_requests: @milestone.sorted_merge_requests, # rubocop:disable Gitlab/ModuleWithInstanceVariables
           show_project_name: true
         })
       end
@@ -18,7 +18,7 @@ def participants
       format.html { redirect_to milestone_redirect_path }
       format.json do
         render json: tabs_json("shared/milestones/_participants_tab", {
-          users: @milestone.participants
+          users: @milestone.participants # rubocop:disable Gitlab/ModuleWithInstanceVariables
         })
       end
     end
@@ -29,7 +29,7 @@ def labels
       format.html { redirect_to milestone_redirect_path }
       format.json do
         render json: tabs_json("shared/milestones/_labels_tab", {
-          labels: @milestone.labels
+          labels: @milestone.labels # rubocop:disable Gitlab/ModuleWithInstanceVariables
         })
       end
     end
@@ -43,6 +43,7 @@ def tabs_json(partial, data = {})
     }
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def milestone_redirect_path
     if @project
       project_milestone_path(@project, @milestone)
@@ -52,4 +53,5 @@ def milestone_redirect_path
       dashboard_milestone_path(@milestone.safe_title, title: @milestone.title)
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 end

app/controllers/concerns/notes_actions.rb

 module NotesActions
   include RendersNotes
+  include Gitlab::Utils::StrongMemoize
   extend ActiveSupport::Concern
 
   included do
@@ -30,6 +31,7 @@ def index
     render json: notes_json
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def create
     create_params = note_params.merge(
       merge_request_diff_head_sha: params[:merge_request_diff_head_sha],
@@ -47,7 +49,9 @@ def create
       format.html { redirect_back_or_default }
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def update
     @note = Notes::UpdateService.new(project, current_user, note_params).execute(note)
 
@@ -60,6 +64,7 @@ def update
       format.html { redirect_back_or_default }
     end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def destroy
     if note.editable?
@@ -138,7 +143,7 @@ def diff_discussion_html(discussion)
         end
     else
       template = "discussions/_diff_discussion"
-      @fresh_discussion = true
+      @fresh_discussion = true # rubocop:disable Gitlab/ModuleWithInstanceVariables
 
       locals = { discussions: [discussion], on_image: on_image }
     end
@@ -191,7 +196,7 @@ def set_polling_interval_header
   end
 
   def noteable
-    @noteable ||= notes_finder.target || @note&.noteable
+    @noteable ||= notes_finder.target || @note&.noteable # rubocop:disable Gitlab/ModuleWithInstanceVariables
   end
 
   def require_noteable!
@@ -211,20 +216,21 @@ def note_serializer
   end
 
   def note_project
-    return @note_project if defined?(@note_project)
-    return nil unless project
+    strong_memoize(:note_project) do
+      return nil unless project
 
-    note_project_id = params[:note_project_id]
+      note_project_id = params[:note_project_id]
 
-    @note_project =
-      if note_project_id.present?
-        Project.find(note_project_id)
-      else
-        project
-      end
+      the_project =
+        if note_project_id.present?
+          Project.find(note_project_id)
+        else
+          project
+        end
 
-    return access_denied! unless can?(current_user, :create_note, @note_project)
+      return access_denied! unless can?(current_user, :create_note, the_project)
 
-    @note_project
+      the_project
+    end
   end
 end

app/controllers/concerns/oauth_applications.rb

@@ -14,6 +14,6 @@ def prepare_scopes
   end
 
   def load_scopes
-    @scopes = Doorkeeper.configuration.scopes
+    @scopes ||= Doorkeeper.configuration.scopes
   end
 end

app/controllers/concerns/preview_markdown.rb

 module PreviewMarkdown
   extend ActiveSupport::Concern
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def preview_markdown
     result = PreviewMarkdownService.new(@project, current_user, params).execute
 
@@ -20,4 +21,5 @@ def preview_markdown
       }
     }
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 end

app/controllers/concerns/renders_commits.rb

 module RendersCommits
   def prepare_commits_for_rendering(commits)
-    Banzai::CommitRenderer.render(commits, @project, current_user)
+    Banzai::CommitRenderer.render(commits, @project, current_user) # rubocop:disable Gitlab/ModuleWithInstanceVariables
 
     commits
   end

app/controllers/concerns/renders_notes.rb

 module RendersNotes
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def prepare_notes_for_rendering(notes, noteable = nil)
     preload_noteable_for_regular_notes(notes)
     preload_max_access_for_authors(notes, @project)
@@ -7,6 +8,7 @@ def prepare_notes_for_rendering(notes, noteable = nil)
 
     notes
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   private
 

app/controllers/concerns/service_params.rb

@@ -66,7 +66,7 @@ module ServiceParams
   FILTER_BLANK_PARAMS = [:password].freeze
 
   def service_params
-    dynamic_params = @service.event_channel_names + @service.event_names
+    dynamic_params = @service.event_channel_names + @service.event_names # rubocop:disable Gitlab/ModuleWithInstanceVariables
     service_params = params.permit(:id, service: ALLOWED_PARAMS_CE + dynamic_params)
 
     if service_params[:service].is_a?(Hash)

app/controllers/concerns/snippets_actions.rb

@@ -4,6 +4,7 @@ module SnippetsActions
   def edit
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def raw
     disposition = params[:inline] == 'false' ? 'attachment' : 'inline'
 
@@ -14,6 +15,7 @@ def raw
       filename: @snippet.sanitized_file_name
     )
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   private
 

app/controllers/concerns/spammable_actions.rb

@@ -2,6 +2,7 @@ module SpammableActions
   extend ActiveSupport::Concern
 
   include Recaptcha::Verify
+  include Gitlab::Utils::StrongMemoize
 
   included do
     before_action :authorize_submit_spammable!, only: :mark_as_spam
@@ -18,9 +19,9 @@ def mark_as_spam
   private
 
   def ensure_spam_config_loaded!
-    return @spam_config_loaded if defined?(@spam_config_loaded)
-
-    @spam_config_loaded = Gitlab::Recaptcha.load_configurations!
+    strong_memoize(:spam_config_loaded) do
+      Gitlab::Recaptcha.load_configurations!
+    end
   end
 
   def recaptcha_check_with_fallback(should_redirect = true, &fallback)

app/controllers/concerns/toggle_subscription_action.rb

@@ -12,7 +12,7 @@ def toggle_subscription
   private
 
   def subscribable_project
-    @project || raise(NotImplementedError)
+    @project ||= raise(NotImplementedError)
   end
 
   def subscribable_resource

app/models/concerns/mentionable.rb

@@ -44,13 +44,11 @@ def local_reference
   end
 
   def all_references(current_user = nil, extractor: nil)
-    @extractors ||= {}
-
     # Use custom extractor if it's passed in the function parameters.
     if extractor
-      @extractors[current_user] = extractor
+      extractors[current_user] = extractor
     else
-      extractor = @extractors[current_user] ||= Gitlab::ReferenceExtractor.new(project, current_user)
+      extractor = extractors[current_user] ||= Gitlab::ReferenceExtractor.new(project, current_user)
 
       extractor.reset_memoized_values
     end
@@ -69,6 +67,10 @@ def all_references(current_user = nil, extractor: nil)
     extractor
   end
 
+  def extractors
+    @extractors ||= {}
+  end
+
   def mentioned_users(current_user = nil)
     all_references(current_user).users
   end

app/models/concerns/milestoneish.rb

@@ -103,9 +103,11 @@ def count_issues_by_state(user)
   end
 
   def memoize_per_user(user, method_name)
-    @memoized ||= {}
-    @memoized[method_name] ||= {}
-    @memoized[method_name][user&.id] ||= yield
+    memoized_users[method_name][user&.id] ||= yield
+  end
+
+  def memoized_users
+    @memoized_users ||= Hash.new { |h, k| h[k] = {} }
   end
 
   # override in a class that includes this module to get a faster query

app/models/concerns/noteable.rb

@@ -46,6 +46,7 @@ def grouped_diff_discussions(*args)
     notes.inc_relations_for_view.grouped_diff_discussions(*args)
   end
 
+  # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def resolvable_discussions
     @resolvable_discussions ||=
       if defined?(@discussions)
@@ -54,6 +55,7 @@ def resolvable_discussions
         discussion_notes.resolvable.discussions(self)
       end
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def discussions_resolvable?
     resolvable_discussions.any?(&:resolvable?)

app/models/concerns/participable.rb

@@ -56,15 +56,17 @@ def participant(attr)
   #
   # Returns an Array of User instances.
   def participants(current_user = nil)
-    @participants ||= Hash.new do |hash, user|
-      hash[user] = raw_participants(user)
-    end
-
-    @participants[current_user]
+    all_participants[current_user]
   end
 
   private
 
+  def all_participants
+    @all_participants ||= Hash.new do |hash, user|
+      hash[user] = raw_participants(user)
+    end
+  end
+
   def raw_participants(current_user = nil)
     current_user ||= author
     ext = Gitlab::ReferenceExtractor.new(project, current_user)

app/models/concerns/relative_positioning.rb

@@ -52,7 +52,7 @@ def move_between(before, after)
     # to its predecessor. This process will recursively move all the predecessors until we have a place
     if (after.relative_position - before.relative_position) < 2
       before.move_before
-      @positionable_neighbours = [before]
+      @positionable_neighbours = [before] # rubocop:disable Gitlab/ModuleWithInstanceVariables
     end
 
     self.relative_position = position_between(before.relative_position, after.relative_position)
@@ -65,7 +65,7 @@ def move_after(before = self)
     if before.shift_after?
       issue_to_move = self.class.in_projects(project_ids).find_by!(relative_position: pos_after)
       issue_to_move.move_after