[Fix rubocop#3445] Handle properly setter methods auto-correct in Sty…

…le/AndOr (rubocop#3454)

CHANGELOG.md

@@ -12,6 +12,7 @@
 
 ### Bug fixes
 
+* [#3445](https://github.com/bbatsov/rubocop/issues/3445): Fix bad autocorrect for `Style/AndOr` cop. ([@mikezter][])
 * [#3349](https://github.com/bbatsov/rubocop/issues/3349): Fix bad autocorrect for `Style/Lambda` cop. ([@metcalf][])
 * [#3351](https://github.com/bbatsov/rubocop/issues/3351): Fix bad auto-correct for `Performance/RedundantMatch` cop. ([@annaswims][])
 * [#3347](https://github.com/bbatsov/rubocop/issues/3347): Prevent infinite loop in `Style/TernaryParentheses` cop when used together with `Style/RedundantParentheses`. ([@drenmi][])
@@ -2335,3 +2336,4 @@
 [@annaswims]: https://github.com/annaswims
 [@soutaro]: https://github.com/soutaro
 [@nicklamuro]: https://github.com/nicklamuro
+[@mikezter]: https://github.com/mikezter

lib/rubocop/cop/style/and_or.rb

@@ -78,12 +78,19 @@ def autocorrect(node)
         def correct_send(node, corrector)
           receiver, method_name, *args = *node
           return correct_not(node, receiver, corrector) if method_name == :!
+          return correct_setter(node, corrector) if setter_method?(method_name)
           return unless correctable_send?(node)
 
           corrector.replace(whitespace_before_arg(node), '('.freeze)
           corrector.insert_after(args.last.source_range, ')'.freeze)
         end
 
+        def correct_setter(node, corrector)
+          receiver, _method_name, *args = *node
+          corrector.insert_before(receiver.source_range, '('.freeze)
+          corrector.insert_after(args.last.source_range, ')'.freeze)
+        end
+
         # ! is a special case:
         # 'x and !obj.method arg' can be auto-corrected if we
         # recurse down a level and add parens to 'obj.method arg'
@@ -106,6 +113,10 @@ def correct_other(node, corrector)
           corrector.insert_after(node.source_range, ')')
         end
 
+        def setter_method?(method_name)
+          method_name.to_s.end_with?('=')
+        end
+
         def correctable_send?(node)
           _receiver, method_name, *args = *node
           # don't clobber if we already have a starting paren

spec/rubocop/cop/style/and_or_spec.rb

@@ -253,6 +253,20 @@
       end
     end
 
+    context 'with obj.method = arg on left' do
+      it 'autocorrects "and" with && and adds parens' do
+        new_source = autocorrect_source(cop, 'obj.method = arg and x')
+        expect(new_source).to eq('(obj.method = arg) && x')
+      end
+    end
+
+    context 'with obj.method= arg on left' do
+      it 'autocorrects "and" with && and adds parens' do
+        new_source = autocorrect_source(cop, 'obj.method= arg and x')
+        expect(new_source).to eq('(obj.method= arg) && x')
+      end
+    end
+
     context 'with predicate method with arg without space on right' do
       it 'autocorrects "or" with || and adds parens' do
         new_source = autocorrect_source(cop, 'false or 3.is_a?Integer')