createContainer called with pre-0.31 argument list — onCaughtError is null, crashing the process on any caught error

[joemckie]

Summary

createContainer is called with the pre-0.31 (React 18-era) argument list, but the package depends on react-reconciler@^0.31.0. Two of the three error callbacks land in the wrong slots and onCaughtError ends up null.

The practical effect: any error caught by an <ErrorBoundary> crashes the process with a misleading TypeError: onCaughtError is not a function, instead of being reported. onRecoverableError is also never wired.

Current call

src/reconciler/render.ts (dist/reconciler/render.js:82):

const container = TuiReconciler.createContainer(root, 0, null, false, null, "", onRecoverableError, null);

That's 8 arguments. The 0.31 signature takes 10:

exports.createContainer = function (
  containerInfo, tag, hydrationCallbacks, isStrictMode,
  concurrentUpdatesByDefaultOverride, identifierPrefix,
  onUncaughtError, onCaughtError, onRecoverableError, transitionCallbacks
) { … }

So currently:

slot	gets	should get
onUncaughtError	onRecoverableError	uncaught handler
onCaughtError	null	caught handler
onRecoverableError	undefined	recoverable handler

The uncaught path works by luck — storm's handler happens to land in the right slot. The caught path is null, so logCaughtError's root.onCaughtError(...) throws.

src/reconciler/render-to-string.ts (dist/reconciler/render-to-string.js:71) has the same 8-arg call, which means renderToString silently fails to collect errors from error boundaries and recoverable errors.

Reproduction

npm install @orchetron/storm@0.2.0 react@19

// repro.tsx — any error inside an ErrorBoundary will do
import { render, Box, Text, ErrorBoundary } from "@orchetron/storm";
import React from "react";

function Boom(): React.ReactNode {
  throw new Error("boom");
}

render(
  <ErrorBoundary fallback={(err) => <Text>caught: {err.message}</Text>}>
    <Box><Boom /></Box>
  </ErrorBoundary>,
);

The fallback paints caught: boom, and then:

Uncaught exception: TypeError: onCaughtError is not a function
    at logCaughtError (…/react-reconciler/cjs/react-reconciler.development.js:5524:9)
    at runWithFiberInDEV (…/react-reconciler/cjs/react-reconciler.development.js:522:16)
    at inst.componentDidCatch.update.callback (…/react-reconciler/cjs/react-reconciler.development.js:5571:11)
    at callCallback (…/react-reconciler/cjs/react-reconciler.development.js:2516:16)
    …
…/@orchetron/storm/dist/core/screen.js:77
            throw err;
            ^

Screen.onUncaughtException rethrows, so the process dies. Because this fires from the error boundary's own commit, it replaces whatever the real error was — the boundary renders its fallback for a frame and then the process exits, so the underlying error is effectively invisible. That's how it presented for me: a genuine bug in my tree (#21) was completely masked by this.

Suggested fix

const onCaughtError = (err) => {
    if (options.onError) options.onError(err);
};
const container = TuiReconciler.createContainer(
    root, 0, null, false, null, "",
    onRecoverableError,  // onUncaughtError
    onCaughtError,       // onCaughtError
    onRecoverableError,  // onRecoverableError
    null,
);

Judgement call worth your input: I deliberately did not route onCaughtError to the default stderr writer. An <ErrorBoundary> that caught an error is already showing its fallback, so writing a raw stack to stderr scribbles over the alt screen. Forwarding only to a user-supplied options.onError seemed right, but you may prefer always logging, or adding a separate option.

For render-to-string.ts the fix is simpler — the same collector in all three slots:

const collect = (error) => { errors.push(error); };
const container = TuiReconciler.createContainer(root, 0, null, false, null, "", collect, collect, collect, null);

Possibly related: peer range

package.json declares:

"peerDependencies": { "react": "^18.0.0 || ^19.0.0" },
"dependencies": { "react-reconciler": "^0.31.0" }

but react-reconciler@0.31.0 itself declares "peerDependencies": { "react": "^19.0.0" }. The ^18.0.0 half of that range can't work regardless of this fix — worth narrowing to ^19.0.0 so React 18 users fail at install rather than at runtime. I haven't actually tried it on React 18, so I may be missing something.

Environment

• @orchetron/storm 0.2.0 (latest on npm)
• react 19.2.8, react-reconciler 0.31.0
• Node 24.15.0, Linux