Upgrade to Rubocop 0.68.1

This adds Ruby 2.6 support.

Gemfile

@@ -349,9 +349,10 @@ group :development, :test do
   gem 'spring', '~> 2.0.0'
   gem 'spring-commands-rspec', '~> 1.0.4'
 
-  gem 'gitlab-styles', '~> 2.5', require: false
+  gem 'gitlab-styles', '~> 2.6', require: false
   # Pin these dependencies, otherwise a new rule could break the CI pipelines
-  gem 'rubocop', '~> 0.54.0'
+  gem 'rubocop', '~> 0.68.1'
+  gem 'rubocop-performance', '~> 1.1.0'
   gem 'rubocop-rspec', '~> 1.22.1'
 
   gem 'scss_lint', '~> 0.56.0', require: false

Gemfile.lock

@@ -297,9 +297,10 @@ GEM
     gitlab-markup (1.7.0)
     gitlab-sidekiq-fetcher (0.4.0)
       sidekiq (~> 5)
-    gitlab-styles (2.5.2)
-      rubocop (~> 0.54.0)
+    gitlab-styles (2.6.1)
+      rubocop (~> 0.68.1)
       rubocop-gitlab-security (~> 0.1.0)
+      rubocop-performance (~> 1.1.0)
       rubocop-rspec (~> 1.19)
     gitlab_omniauth-ldap (2.1.1)
       net-ldap (~> 0.16)
@@ -407,6 +408,7 @@ GEM
     jaeger-client (0.10.0)
       opentracing (~> 0.3)
       thrift
+    jaro_winkler (1.5.2)
     jira-ruby (1.4.1)
       activesupport
       multipart-post
@@ -585,7 +587,7 @@ GEM
       rubypants (~> 0.2)
     orm_adapter (0.5.0)
     os (1.0.0)
-    parallel (1.12.1)
+    parallel (1.17.0)
     parser (2.5.3.0)
       ast (~> 2.4.0)
     parslet (1.8.2)
@@ -615,7 +617,6 @@ GEM
     pg (1.1.4)
     po_to_json (1.0.1)
       json (>= 1.6.0)
-    powerpack (0.1.1)
     premailer (1.10.4)
       addressable
       css_parser (>= 1.4.10)
@@ -787,15 +788,17 @@ GEM
       pg
       rails
       sqlite3
-    rubocop (0.54.0)
+    rubocop (0.68.1)
+      jaro_winkler (~> 1.5.1)
       parallel (~> 1.10)
-      parser (>= 2.5)
-      powerpack (~> 0.1)
+      parser (>= 2.5, != 2.5.1.1)
       rainbow (>= 2.2.2, < 4.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (~> 1.0, >= 1.0.1)
+      unicode-display_width (>= 1.4.0, < 1.6)
     rubocop-gitlab-security (0.1.1)
       rubocop (>= 0.51)
+    rubocop-performance (1.1.0)
+      rubocop (>= 0.67.0)
     rubocop-rspec (1.22.2)
       rubocop (>= 0.52.1)
     ruby-enum (0.7.2)
@@ -803,7 +806,7 @@ GEM
     ruby-fogbugz (0.2.1)
       crack (~> 0.4)
     ruby-prof (0.17.0)
-    ruby-progressbar (1.9.0)
+    ruby-progressbar (1.10.0)
     ruby-saml (1.7.2)
       nokogiri (>= 1.5.10)
     ruby_parser (3.11.0)
@@ -929,7 +932,7 @@ GEM
     unf (0.1.4)
       unf_ext
     unf_ext (0.0.7.5)
-    unicode-display_width (1.3.2)
+    unicode-display_width (1.5.0)
     unicorn (5.4.1)
       kgio (~> 2.6)
       raindrops (~> 0.7)
@@ -1065,7 +1068,7 @@ DEPENDENCIES
   gitlab-labkit (~> 0.2.0)
   gitlab-markup (~> 1.7.0)
   gitlab-sidekiq-fetcher (~> 0.4.0)
-  gitlab-styles (~> 2.5)
+  gitlab-styles (~> 2.6)
   gitlab_omniauth-ldap (~> 2.1.1)
   gon (~> 6.2)
   google-api-client (~> 0.23)
@@ -1171,7 +1174,8 @@ DEPENDENCIES
   rspec-set (~> 0.1.3)
   rspec_junit_formatter
   rspec_profiling (~> 0.0.5)
-  rubocop (~> 0.54.0)
+  rubocop (~> 0.68.1)
+  rubocop-performance (~> 1.1.0)
   rubocop-rspec (~> 1.22.1)
   ruby-fogbugz (~> 0.2.1)
   ruby-prof (~> 0.17.0)

rubocop/cop/gitlab/finder_with_find_by.rb

@@ -2,7 +2,7 @@ module RuboCop
   module Cop
     module Gitlab
       class FinderWithFindBy < RuboCop::Cop::Cop
-        FIND_PATTERN = /\Afind(_by\!?)?\z/
+        FIND_PATTERN = /\Afind(_by\!?)?\z/.freeze
         ALLOWED_MODULES = ['FinderMethods'].freeze
 
         def message(used_method)
@@ -36,7 +36,7 @@ module RuboCop
         def find_on_execute?(node)
           chained_on_node = node.descendants.first
           node.method_name.to_s =~ FIND_PATTERN &&
-            chained_on_node&.method_name == :execute
+            chained_on_node.is_a?(RuboCop::AST::SendNode) && chained_on_node.method_name == :execute
         end
 
         def allowed_module?(node)