Support WeakReferences in NodeConnectingVisitor

nikic · Jan 1, 2025 · 4cac2f2 · 4cac2f2
1 parent 7d3039c
commit 4cac2f2
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Showing 2 changed files with 42 additions and 3 deletions.
diff --git a/lib/PhpParser/NodeVisitor/NodeConnectingVisitor.php b/lib/PhpParser/NodeVisitor/NodeConnectingVisitor.php
@@ -25,19 +25,34 @@ final class NodeConnectingVisitor extends NodeVisitorAbstract {
      */
     private $previous;
 
+    private bool $weakReferences;
+
+    public function __construct(bool $weakReferences = false) {
+        $this->weakReferences = $weakReferences;
+    }
+
     public function beforeTraverse(array $nodes) {
         $this->stack    = [];
         $this->previous = null;
     }
 
     public function enterNode(Node $node) {
         if (!empty($this->stack)) {
-            $node->setAttribute('parent', $this->stack[count($this->stack) - 1]);
+            $parent = $this->stack[count($this->stack) - 1];
+            if ($this->weakReferences) {
+                $parent = \WeakReference::create($parent);
+            }
+            $node->setAttribute('parent', $parent);
         }
 
         if ($this->previous !== null && $this->previous->getAttribute('parent') === $node->getAttribute('parent')) {
-            $node->setAttribute('previous', $this->previous);
-            $this->previous->setAttribute('next', $node);
+            if ($this->weakReferences) {
+                $node->setAttribute('previous', \WeakReference::create($this->previous));
+                $this->previous->setAttribute('next', \WeakReference::create($node));
+            } else {
+                $node->setAttribute('previous', $this->previous);
+                $this->previous->setAttribute('next', $node);
+            }
         }
 
         $this->stack[] = $node;

diff --git a/test/PhpParser/NodeVisitor/NodeConnectingVisitorTest.php b/test/PhpParser/NodeVisitor/NodeConnectingVisitorTest.php
@@ -30,4 +30,28 @@ public function testConnectsNodeToItsParentNodeAndItsSiblingNodes(): void {
 
         $this->assertSame(Else_::class, get_class($node->getAttribute('next')));
     }
+
+    public function testWeakReferences(): void {
+        $ast = (new ParserFactory())->createForNewestSupportedVersion()->parse(
+            '<?php if (true) {} else {}'
+        );
+
+        $traverser = new NodeTraverser();
+
+        $traverser->addVisitor(new NodeConnectingVisitor(true));
+
+        $ast = $traverser->traverse($ast);
+
+        $node = (new NodeFinder())->findFirstInstanceof($ast, Else_::class);
+
+        $this->assertInstanceOf(\WeakReference::class, $node->getAttribute('parent'));
+        $this->assertSame(If_::class, get_class($node->getAttribute('parent')->get()));
+        $this->assertInstanceOf(\WeakReference::class, $node->getAttribute('previous'));
+        $this->assertSame(ConstFetch::class, get_class($node->getAttribute('previous')->get()));
+
+        $node = (new NodeFinder())->findFirstInstanceof($ast, ConstFetch::class);
+
+        $this->assertInstanceOf(\WeakReference::class, $node->getAttribute('next'));
+        $this->assertSame(Else_::class, get_class($node->getAttribute('next')->get()));
+    }
 }