Enable and autocorrect the CustomErrorClass cop

app/controllers/projects/blob_controller.rb

@@ -5,7 +5,7 @@ class Projects::BlobController < Projects::ApplicationController
   include ActionView::Helpers::SanitizeHelper
   # Raised when given an invalid file path
-  class InvalidPathError < StandardError; end
+  InvalidPathError = Class.new(StandardError)
   before_action :require_non_empty_project, except: [:new, :create]
   before_action :authorize_download_code!

app/models/project.rb

@@ -19,7 +19,7 @@ class Project < ActiveRecord::Base
   extend Gitlab::ConfigHelper
-  class BoardLimitExceeded < StandardError; end
+  BoardLimitExceeded = Class.new(StandardError)
   NUMBER_OF_PERMITTED_BOARDS = 1
   UNKNOWN_IMPORT_URL = 'http://unknown.git'.freeze

app/models/project_wiki.rb

@@ -7,7 +7,7 @@ class ProjectWiki
     'AsciiDoc' => :asciidoc
   }.freeze unless defined?(MARKUPS)
-  class CouldNotCreateWikiError < StandardError; end
+  CouldNotCreateWikiError = Class.new(StandardError)
   # Returns a string describing what went wrong after
   # an operation fails.

app/serializers/pipeline_serializer.rb

 class PipelineSerializer < BaseSerializer
-  class InvalidResourceError < StandardError; end
+  InvalidResourceError = Class.new(StandardError)
   entity PipelineEntity

app/services/commits/change_service.rb

 module Commits
   class ChangeService < ::BaseService
-    class ValidationError < StandardError; end
-    class ChangeError < StandardError; end
+    ValidationError = Class.new(StandardError)
+    ChangeError = Class.new(StandardError)
     def execute
       @start_project = params[:start_project] || @project

app/services/files/base_service.rb

 module Files
   class BaseService < ::BaseService
-    class ValidationError < StandardError; end
+    ValidationError = Class.new(StandardError)
     def execute
       @start_project = params[:start_project] || @project

app/services/files/multi_service.rb

 module Files
   class MultiService < Files::BaseService
-    class FileChangedError < StandardError; end
+    FileChangedError = Class.new(StandardError)
     ACTIONS = %w[create update delete move].freeze

app/services/files/update_service.rb

 module Files
   class UpdateService < Files::BaseService
-    class FileChangedError < StandardError; end
+    FileChangedError = Class.new(StandardError)
     def commit
       repository.update_file(current_user, @file_path, @file_content,

app/services/issues/move_service.rb

 module Issues
   class MoveService < Issues::BaseService
-    class MoveError < StandardError; end
+    MoveError = Class.new(StandardError)
     def execute(issue, new_project)
       @old_issue = issue

app/services/merge_requests/resolve_service.rb

 module MergeRequests
   class ResolveService < MergeRequests::BaseService
-    class MissingFiles < Gitlab::Conflict::ResolutionError
-    end
+    MissingFiles = Class.new(Gitlab::Conflict::ResolutionError)
     attr_accessor :conflicts, :rugged, :merge_index, :merge_request

app/services/projects/destroy_service.rb

@@ -2,7 +2,7 @@ module Projects
   class DestroyService < BaseService
     include Gitlab::ShellAdapter
-    class DestroyError < StandardError; end
+    DestroyError = Class.new(StandardError)
     DELETED_FLAG = '+deleted'.freeze

app/services/projects/import_service.rb

@@ -2,7 +2,7 @@ module Projects
   class ImportService < BaseService
     include Gitlab::ShellAdapter
-    class Error < StandardError; end
+    Error = Class.new(StandardError)
     def execute
       add_repository_to_project unless project.gitlab_project_import?

app/services/projects/transfer_service.rb

@@ -9,7 +9,7 @@
 module Projects
   class TransferService < BaseService
     include Gitlab::ShellAdapter
-    class TransferError < StandardError; end
+    TransferError = Class.new(StandardError)
     def execute(new_namespace)
       if allowed_transfer?(current_user, project, new_namespace)

lib/api/api_guard.rb

@@ -160,13 +160,10 @@ module API
     # Exceptions
     #
-    class MissingTokenError < StandardError; end
-
-    class TokenNotFoundError < StandardError; end
-
-    class ExpiredError < StandardError; end
-
-    class RevokedError < StandardError; end
+    MissingTokenError = Class.new(StandardError)
+    TokenNotFoundError = Class.new(StandardError)
+    ExpiredError = Class.new(StandardError)
+    RevokedError = Class.new(StandardError)
     class InsufficientScopeError < StandardError
       attr_reader :scopes

lib/bitbucket/error/unauthorized.rb

 module Bitbucket
   module Error
-    class Unauthorized < StandardError
-    end
+    Unauthorized = Class.new(StandardError)
   end
 end

lib/ci/gitlab_ci_yaml_processor.rb

 module Ci
   class GitlabCiYamlProcessor
-    class ValidationError < StandardError; end
+    ValidationError = Class.new(StandardError)
     include Gitlab::Ci::Config::Entry::LegacyValidationHelpers

lib/extracts_path.rb

@@ -2,7 +2,7 @@
 # file path string when combined in a request parameter
 module ExtractsPath
   # Raised when given an invalid file path
-  class InvalidPathError < StandardError; end
+  InvalidPathError = Class.new(StandardError)
   # Given a string containing both a Git tree-ish, such as a branch or tag, and
   # a filesystem path joined by forward slashes, attempts to separate the two.

lib/gitlab/access.rb

@@ -5,7 +5,7 @@
 #
 module Gitlab
   module Access
-    class AccessDeniedError < StandardError; end
+    AccessDeniedError = Class.new(StandardError)
     NO_ACCESS = 0
     GUEST     = 10

lib/gitlab/auth.rb

 module Gitlab
   module Auth
-    class MissingPersonalTokenError < StandardError; end
+    MissingPersonalTokenError = Class.new(StandardError)
     SCOPES = [:api, :read_user].freeze
     DEFAULT_SCOPES = [:api].freeze

lib/gitlab/ci/build/artifacts/metadata.rb

@@ -6,7 +6,7 @@ module Gitlab
     module Build
       module Artifacts
         class Metadata
-          class ParserError < StandardError; end
+          ParserError = Class.new(StandardError)
           VERSION_PATTERN = /^[\w\s]+(\d+\.\d+\.\d+)/
           INVALID_PATH_PATTERN = %r{(^\.?\.?/)|(/\.?\.?/)}