Support Rails 7 enum syntax for Rails/EnumUniqueness cop

[ytjmt]

Rails 7.0 introduced a new enum syntax ( rails/rails#41328 ):

enum :status, [:active, :archived]

Rails/EnumUniqueness cop does't support the new syntax yet. This PR adds the new syntax support.

---

Before submitting the PR make sure the following are checked:

• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences.
• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Ran bundle exec rake default. It executes all tests and runs RuboCop on its own code.
• Added an entry (file) to the changelog folder named {change_type}_{change_description}.md if the new code introduces user-observable changes. See changelog entry format for details.
• If this is a new cop, consider making a corresponding update to the Rails Style Guide.

[ytjmt]

refactor to suppress Metrics/AbcSize and Metrics/MethodLength offences.

Details

$ bundle exec rubocop lib/rubocop/cop/rails/enum_uniqueness.rb
Inspecting 1 file
C

Offenses:

lib/rubocop/cop/rails/enum_uniqueness.rb:50:9: C: Metrics/AbcSize: Assignment Branch Condition size for on_send is too high. [<9, 19, 4> 21.4/17]
        def on_send(node) ...
        ^^^^^^^^^^^^^^^^^
lib/rubocop/cop/rails/enum_uniqueness.rb:50:9: C: Metrics/MethodLength: Method has too many lines. [16/14]
        def on_send(node) ...
        ^^^^^^^^^^^^^^^^^

1 file inspected, 2 offenses detected


$ git diff lib/rubocop/cop/rails/enum_uniqueness.rb 
diff --git a/lib/rubocop/cop/rails/enum_uniqueness.rb b/lib/rubocop/cop/rails/enum_uniqueness.rb
index 2885315a..4b1e4230 100644
--- a/lib/rubocop/cop/rails/enum_uniqueness.rb
+++ b/lib/rubocop/cop/rails/enum_uniqueness.rb
@@ -56,9 +56,13 @@ module RuboCop
 
           enum_with_old_syntax?(node) do |pairs|
             pairs.each do |pair|
+              items = args.values
+
+              next unless duplicates?(items)
+
               enum_values(pair) do |key, args|
                 consecutive_duplicates(args.values).each do |item|
-                  add_offense(item, message: message(key, item))
+                  add_offense(item, message: format(MSG, value: item.source, enum: enum_name(key)))
                 end
               end
             end

[koic]

Thanks!