From ba2d06039eb07166672973f9fe994c6a39a933c7 Mon Sep 17 00:00:00 2001
From: Sunny Ripert <sunny@sunfox.org>
Date: Tue, 15 Mar 2022 09:18:09 +0100
Subject: [PATCH] Only consider migration classes for `MigrationClassName`

---
 ...ider_migration_classes_for_migration_class_name.md |  1 +
 lib/rubocop/cop/rails/migration_class_name.rb         |  3 +++
 spec/rubocop/cop/rails/migration_class_name_spec.rb   | 11 +++++++++++
 3 files changed, 15 insertions(+)
 create mode 100644 changelog/fix_only_consider_migration_classes_for_migration_class_name.md

diff --git a/changelog/fix_only_consider_migration_classes_for_migration_class_name.md b/changelog/fix_only_consider_migration_classes_for_migration_class_name.md
new file mode 100644
index 0000000000..4b7937396f
--- /dev/null
+++ b/changelog/fix_only_consider_migration_classes_for_migration_class_name.md
@@ -0,0 +1 @@
+* [#657](https://github.com/rubocop/rubocop-rails/pull/657): Only consider migration classes for `Rails/MigrationClassName`. ([@sunny][])
diff --git a/lib/rubocop/cop/rails/migration_class_name.rb b/lib/rubocop/cop/rails/migration_class_name.rb
index 09d9011743..b99dc70bf7 100644
--- a/lib/rubocop/cop/rails/migration_class_name.rb
+++ b/lib/rubocop/cop/rails/migration_class_name.rb
@@ -20,10 +20,13 @@ module Rails
       #
       class MigrationClassName < Base
         extend AutoCorrector
+        include MigrationsHelper
 
         MSG = 'Replace with `%<corrected_class_name>s` that matches the file name.'
 
         def on_class(node)
+          return if in_migration?(node)
+
           snake_class_name = to_snakecase(node.identifier.source)
 
           return if snake_class_name == basename_without_timestamp
diff --git a/spec/rubocop/cop/rails/migration_class_name_spec.rb b/spec/rubocop/cop/rails/migration_class_name_spec.rb
index feae99d044..907686eb0c 100644
--- a/spec/rubocop/cop/rails/migration_class_name_spec.rb
+++ b/spec/rubocop/cop/rails/migration_class_name_spec.rb
@@ -10,6 +10,17 @@ class CreateUsers < ActiveRecord::Migration[7.0]
         end
       RUBY
     end
+
+    context 'when defining another class' do
+      it 'does not register an offense' do
+        expect_no_offenses(<<~RUBY, filename)
+          class CreateUsers < ActiveRecord::Migration[7.0]
+            class Article < ActiveRecord::Base
+            end
+          end
+        RUBY
+      end
+    end
   end
 
   context 'when the class name does not match its file name' do