discord · paulshen · Jun 6, 2019 · Jun 6, 2019 · Jun 6, 2019 · Jun 6, 2019
diff --git a/packages/react-dom/src/client/ReactDOMComponentTree.js b/packages/react-dom/src/client/ReactDOMComponentTree.js
@@ -8,11 +8,11 @@
 import {HostComponent, HostText} from 'shared/ReactWorkTags';
 import invariant from 'shared/invariant';
 
-const randomKey = Math.random()
-  .toString(36)
-  .slice(2);
-const internalInstanceKey = '__reactInternalInstance$' + randomKey;
-const internalEventHandlersKey = '__reactEventHandlers$' + randomKey;
+// const randomKey = Math.random()
+//   .toString(36)
+//   .slice(2);
+const internalInstanceKey = '__reactInternalInstance$';
+const internalEventHandlersKey = '__reactEventHandlers$';
 
 export function precacheFiberNode(hostInst, node) {
   node[internalInstanceKey] = hostInst;

diff --git a/packages/react-reconciler/src/ReactFiberCommitWork.js b/packages/react-reconciler/src/ReactFiberCommitWork.js
@@ -724,11 +724,20 @@ function commitUnmount(current: Fiber): void {
       if (typeof instance.componentWillUnmount === 'function') {
         safelyCallComponentWillUnmount(current, instance);
       }
-      return;
+      break;
     }
     case HostComponent: {
       safelyDetachRef(current);
-      return;
+      // HACK: detach fiber references from DOM
+      current.stateNode.__reactEventHandlers$ = null;
+      current.stateNode.__reactInternalInstance$ = null;
+      break;
+    }
+    case HostText: {
+      // HACK: detach fiber references from DOM
+      current.stateNode.__reactEventHandlers$ = null;
+      current.stateNode.__reactInternalInstance$ = null;
+      break;
     }
     case HostPortal: {
       // TODO: this is recursive.
@@ -739,9 +748,15 @@ function commitUnmount(current: Fiber): void {
       } else if (supportsPersistence) {
         emptyPortalContainer(current);
       }
-      return;
+      break;
     }
   }
+
+  // Remove reference for GC
+  current.stateNode = null;
+  if (current.alternate != null) {
+    current.alternate.stateNode = null;
+  }
 }
 
 function commitNestedUnmounts(root: Fiber): void {
@@ -1038,19 +1053,15 @@ function unmountHostComponents(current): void {
     }
 
     if (node.tag === HostComponent || node.tag === HostText) {
+      // Save stateNode reference so commitUnmount can clear it.
+      const stateNode: Instance | TextInstance = node.stateNode;
       commitNestedUnmounts(node);
       // After all the children have unmounted, it is now safe to remove the
       // node from the tree.
       if (currentParentIsContainer) {
-        removeChildFromContainer(
-          ((currentParent: any): Container),
-          (node.stateNode: Instance | TextInstance),
-        );
+        removeChildFromContainer(((currentParent: any): Container), stateNode);
       } else {
-        removeChild(
-          ((currentParent: any): Instance),
-          (node.stateNode: Instance | TextInstance),
-        );
+        removeChild(((currentParent: any): Instance), stateNode);
       }
       // Don't visit children because we already visited them.
     } else if (

diff --git a/packages/react-reconciler/src/ReactFiberScheduler.js b/packages/react-reconciler/src/ReactFiberScheduler.js
@@ -562,7 +562,10 @@ function commitPassiveEffects(root: FiberRoot, firstEffect: Fiber): void {
         captureCommitPhaseError(effect, error);
       }
     }
-    effect = effect.nextEffect;
+    const nextNextEffect = effect.nextEffect;
+    // Remove nextEffect pointer to assist GC
+    effect.nextEffect = null;
+    effect = nextNextEffect;
   } while (effect !== null);
   if (__DEV__) {
     resetCurrentFiber();
@@ -811,6 +814,16 @@ function commitRoot(root: FiberRoot, finishedWork: Fiber): void {
       return schedulePassiveEffects(callback);
     });
     passiveEffectCallback = callback;
+  } else {
+    // We are done with the effect chain at this point so let's clear the
+    // nextEffect pointers to assist with GC. If we have passive effects, we'll
+    // clear this in commitPassiveEffects.
+    nextEffect = firstEffect;
+    while (nextEffect !== null) {
+      const nextNextEffect = nextEffect.nextEffect;
+      nextEffect.nextEffect = null;
+      nextEffect = nextNextEffect;
+    }
   }
 
   isCommitting = false;