[Fix rubocop#9928] Fix a false auto-correct for Layout/EndAlignment

Fixes rubocop#9928.

This PR fixes an infinite loop error and a false auto-correction behavior for `Layout/EndAlignment`
when using operator methods and `EnforcedStyleAlignWith: variable`.
This infinite loop error is due to an offense being registered but not auto-corrected.

`EnforcedStyleAlignWith: variable` enforces alignment to variable,
it should be auto-corrected to be aligned to variable even when operator method is used.

changelog/fix_false_autocorrection_for_layout_end_alignment.md

@@ -0,0 +1 @@
+* [#9928](https://github.com/rubocop/rubocop/issues/9928): Fix an infinite loop error and a false auto-correction behavior for `Layout/EndAlignment` when using operator methods and `EnforcedStyleAlignWith: variable`. ([@koic][])

lib/rubocop/cop/layout/end_alignment.rb

@@ -167,7 +167,8 @@ def alignment_node(node)
         def alignment_node_for_variable_style(node)
           return node.parent if node.case_type? && node.argument?
 
-          assignment = node.ancestors.find(&:assignment_or_similar?)
+          assignment = assignment_or_operator_method(node)
+
           if assignment && !line_break_before_keyword?(assignment.source_range, node)
             assignment
           else
@@ -177,6 +178,12 @@ def alignment_node_for_variable_style(node)
             node
           end
         end
+
+        def assignment_or_operator_method(node)
+          node.ancestors.find do |ancestor|
+            ancestor.assignment_or_similar? || ancestor.send_type? && ancestor.operator_method?
+          end
+        end
       end
     end
   end

spec/rubocop/cop/layout/end_alignment_spec.rb

@@ -301,6 +301,44 @@ module Test
     include_examples 'aligned', 'puts 1; while',  'Test',     '        end'
     include_examples 'aligned', 'puts 1; until',  'Test',     '        end'
     include_examples 'aligned', 'puts 1; case',   'a when b', '        end'
+
+    it 'register an offense when using `+` operator method and `end` is not aligned' do
+      expect_offense(<<~RUBY)
+        variable + if condition
+                     foo
+                   else
+                     bar
+                   end
+                   ^^^ `end` at 5, 11 is not aligned with `variable + if` at 1, 0.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        variable + if condition
+                     foo
+                   else
+                     bar
+        end
+      RUBY
+    end
+
+    it 'register an offense when using `-` operator method and `end` is not aligned' do
+      expect_offense(<<~RUBY)
+        variable - if condition
+                     foo
+                   else
+                     bar
+                   end
+                   ^^^ `end` at 5, 11 is not aligned with `variable - if` at 1, 0.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        variable - if condition
+                     foo
+                   else
+                     bar
+        end
+      RUBY
+    end
   end
 
   context 'correct + opposite' do