Skip coalsce assign in RemoveUnusedPrivatePropertyRector (#4491)

Co-authored-by: Benedikt Franke <benedikt@franke.tech>

packages/NodeTypeResolver/PHPStan/Scope/NodeVisitor/AssignedToNodeVisitor.php

@@ -7,6 +7,7 @@
 use PhpParser\Node;
 use PhpParser\Node\Expr\Assign;
 use PhpParser\Node\Expr\AssignOp;
+use PhpParser\Node\Expr\AssignOp\Coalesce;
 use PhpParser\NodeVisitorAbstract;
 use Rector\NodeTypeResolver\Node\AttributeKey;
 use Rector\NodeTypeResolver\PHPStan\Scope\Contract\NodeVisitor\ScopeResolverNodeVisitorInterface;
@@ -22,6 +23,10 @@ public function enterNode(Node $node): ?Node
             return null;
         }
 
+        if ($node instanceof Coalesce) {
+            $node->var->setAttribute(AttributeKey::IS_ASSIGNED_TO, true);
+        }
+
         $node->var->setAttribute(AttributeKey::IS_BEING_ASSIGNED, true);
         $node->expr->setAttribute(AttributeKey::IS_ASSIGNED_TO, true);
 

rules-tests/DeadCode/Rector/Property/RemoveUnusedPrivatePropertyRector/Fixture/null-coalescing-assignment.php.inc

@@ -0,0 +1,11 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Property\RemoveUnusedPrivatePropertyRector\Fixture;
+
+class Foo {
+    private int $bar;
+
+    public function bar(): int {
+        return $this->bar ??= 3;
+    }
+}

rules/DeadCode/NodeAnalyzer/PropertyWriteonlyAnalyzer.php

@@ -43,6 +43,10 @@ public function arePropertyFetchesExclusivelyBeingAssignedTo(array $propertyFetc
                 return false;
             }
 
+            if ((bool) $propertyFetch->getAttribute(AttributeKey::IS_ASSIGNED_TO, false)) {
+                return false;
+            }
+
             if ((bool) $propertyFetch->getAttribute(AttributeKey::IS_BEING_ASSIGNED, false)) {
                 continue;
             }