From c21ed5a3ca43d588cf925fb1ce5cfed28770715a Mon Sep 17 00:00:00 2001
From: Andrew Clark <acdlite@fb.com>
Date: Wed, 28 Mar 2018 18:02:01 -0700
Subject: [PATCH] Fix bug when fatal error is thrown as a result of
 `batch.commit`

Fixes #12474
---
 .../src/__tests__/ReactDOMRoot-test.internal.js        | 10 ++++++++++
 packages/react-reconciler/src/ReactFiberScheduler.js   |  9 ++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/packages/react-dom/src/__tests__/ReactDOMRoot-test.internal.js b/packages/react-dom/src/__tests__/ReactDOMRoot-test.internal.js
index 83633532dca4a..cd00c561b6320 100644
--- a/packages/react-dom/src/__tests__/ReactDOMRoot-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactDOMRoot-test.internal.js
@@ -320,4 +320,14 @@ describe('ReactDOMRoot', () => {
     flush();
     expect(container.textContent).toEqual('1');
   });
+
+  it('handles fatal errors triggered by batch.commit()', () => {
+    const root = ReactDOM.createRoot(container);
+    const batch = root.createBatch();
+    const InvalidType = undefined;
+    expect(() => batch.render(<InvalidType />)).toWarnDev([
+      'React.createElement: type is invalid',
+    ]);
+    expect(() => batch.commit()).toThrow('Element type is invalid');
+  });
 });
diff --git a/packages/react-reconciler/src/ReactFiberScheduler.js b/packages/react-reconciler/src/ReactFiberScheduler.js
index ec4c554182eab..716f963b9df0b 100644
--- a/packages/react-reconciler/src/ReactFiberScheduler.js
+++ b/packages/react-reconciler/src/ReactFiberScheduler.js
@@ -884,7 +884,12 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
         const sourceFiber: Fiber = nextUnitOfWork;
         let returnFiber = sourceFiber.return;
         if (returnFiber === null) {
-          // This is a fatal error.
+          // This is the root. The root could capture its own errors. However,
+          // we don't know if it errors before or after we pushed the host
+          // context. This information is needed to avoid a stack mismatch.
+          // Because we're not sure, treat this as a fatal error. We could track
+          // which phase it fails in, but doesn't seem worth it. At least
+          // for now.
           didFatal = true;
           onUncaughtError(thrownValue);
           break;
@@ -1444,6 +1449,8 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
     // Perform work on root as if the given expiration time is the current time.
     // This has the effect of synchronously flushing all work up to and
     // including the given time.
+    nextFlushedRoot = root;
+    nextFlushedExpirationTime = expirationTime;
     performWorkOnRoot(root, expirationTime, false);
     finishRendering();
   }