UnusedMatchResult: fix false positive with assign operators (#171)

Author: janedbal

src/Visitor/UnusedMatchVisitor.php

@@ -6,6 +6,7 @@
 use PhpParser\Node\Arg;
 use PhpParser\Node\Expr\ArrayItem;
 use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\AssignOp;
 use PhpParser\Node\Expr\BinaryOp\Coalesce;
 use PhpParser\Node\Expr\Match_;
 use PhpParser\Node\Expr\MethodCall;
@@ -76,6 +77,7 @@ private function isUsed(Node $parent): bool
     {
         return $parent instanceof Throw_
             || $parent instanceof Assign
+            || $parent instanceof AssignOp
             || $parent instanceof MethodCall
             || $parent instanceof Return_
             || $parent instanceof Arg

tests/Rule/data/ForbidUnusedMatchResultRule/code.php

@@ -33,6 +33,11 @@ public function testUsed(bool $bool): mixed
             },
         };
 
+        $b += match ($int) {
+            0 => 0,
+            default => 1,
+        };
+
         $this->use(match ($bool) {
             false => new LogicException(),
             true => new RuntimeException(),