Fix missing context to componentDidMount() when double-invoking lifecycles (#19935)

Author: Brian Vaughn

packages/react-reconciler/src/ReactFiberCommitWork.new.js

@@ -2044,7 +2044,7 @@ function invokeLayoutEffectMountInDEV(fiber: Fiber): void {
       }
       case ClassComponent: {
         const instance = fiber.stateNode;
-        invokeGuardedCallback(null, instance.componentDidMount, null);
+        invokeGuardedCallback(null, instance.componentDidMount, instance);
         if (hasCaughtError()) {
           const mountError = clearCaughtError();
           captureCommitPhaseError(fiber, fiber.return, mountError);
@@ -2103,18 +2103,7 @@ function invokeLayoutEffectUnmountInDEV(fiber: Fiber): void {
       case ClassComponent: {
         const instance = fiber.stateNode;
         if (typeof instance.componentWillUnmount === 'function') {
-          invokeGuardedCallback(
-            null,
-            safelyCallComponentWillUnmount,
-            null,
-            fiber,
-            instance,
-            fiber.return,
-          );
-          if (hasCaughtError()) {
-            const unmountError = clearCaughtError();
-            captureCommitPhaseError(fiber, fiber.return, unmountError);
-          }
+          safelyCallComponentWillUnmount(fiber, instance, fiber.return);
         }
         break;
       }

packages/react-reconciler/src/__tests__/ReactDoubleInvokeEvents-test.internal.js

@@ -240,6 +240,45 @@ describe('ReactDoubleInvokeEvents', () => {
     expect(Scheduler).toHaveYielded([]);
   });
 
+  it('passes the right context to class component lifecycles', () => {
+    class App extends React.PureComponent {
+      test() {}
+
+      componentDidMount() {
+        this.test();
+        Scheduler.unstable_yieldValue('componentDidMount');
+      }
+
+      componentDidUpdate() {
+        this.test();
+        Scheduler.unstable_yieldValue('componentDidUpdate');
+      }
+
+      componentWillUnmount() {
+        this.test();
+        Scheduler.unstable_yieldValue('componentWillUnmount');
+      }
+
+      render() {
+        return null;
+      }
+    }
+
+    ReactNoop.act(() => {
+      ReactNoop.render(<App />);
+    });
+
+    if (__DEV__ && __VARIANT__) {
+      expect(Scheduler).toHaveYielded([
+        'componentDidMount',
+        'componentWillUnmount',
+        'componentDidMount',
+      ]);
+    } else {
+      expect(Scheduler).toHaveYielded(['componentDidMount']);
+    }
+  });
+
   it('double invoking works for class components', () => {
     class App extends React.PureComponent {
       componentDidMount() {