[test] Remove the custom `toThrow` override for legacy V8 error messages (#37384)
The custom `toThrow` override in `scripts/jest/matchers/toThrow.js` wrapped the built-in matcher to rewrite the pre-Node-17 V8 error message format ("Cannot read property 'x' of undefined") into the modern one ("Cannot read properties of undefined (reading 'x')"), so the test suite could run on Node 12 to 16. On the Node versions this repo runs on (20 per `.nvmrc`, 24 in CI), V8 only ever produces the modern format, so the override is a passthrough. Mostly removing this because the custom matcher deep-imports `expect/build/toThrowMatchers`, which no longer resolves on Jest 30 because each Jest package is now bundled into a single file, so this removal unblocks the Jest 30 upgrade stacked on top. Co-authored-by: Claude Code (kimi-k3[1m]) <noreply@anthropic.com>
Sebastian "Sebbie" Silbermann committed
Aug 26, 2026 at 19:24 UTC
269bd40a953a5339ad47c643f9b9dbce88ab878d
5 files changed
+9
-61
packages/react-dom/src/__tests__/ReactServerRendering-test.js
+8
-8
@@ -147,7 +147,7 @@ describe('ReactDOMServer', () => {
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it('should throw with silly args', () => {
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expect(
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ReactDOMServer.renderToString.bind(ReactDOMServer, {x: 123}),
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- ).toThrowError(
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+ ).toThrow(
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'Objects are not valid as a React child (found: object with keys {x})',
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);
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});
@@ -155,7 +155,7 @@ describe('ReactDOMServer', () => {
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it('should throw prop mapping error for an <iframe /> with invalid props', () => {
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expect(() => {
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ReactDOMServer.renderToString(<iframe style="border:none;" />);
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- }).toThrowError(
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+ }).toThrow(
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'The `style` prop expects a mapping from style properties to values, not ' +
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"a string. For example, style={{marginRight: spacing + 'em'}} when using JSX.",
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);
@@ -290,7 +290,7 @@ describe('ReactDOMServer', () => {
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it('should throw with silly args', () => {
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expect(
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ReactDOMServer.renderToStaticMarkup.bind(ReactDOMServer, {x: 123}),
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- ).toThrowError(
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+ ).toThrow(
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'Objects are not valid as a React child (found: object with keys {x})',
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);
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});
@@ -715,7 +715,7 @@ describe('ReactDOMServer', () => {
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<span key={2} />
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</Wrapper>,
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);
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- }).toThrowError(/Cannot assign to read only property.*/);
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+ }).toThrow(/Cannot assign to read only property.*/);
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} else {
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expect(
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ReactDOMServer.renderToStaticMarkup(
@@ -966,7 +966,7 @@ describe('ReactDOMServer', () => {
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expect(() => {
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ReactDOMServer.renderToString(<Foo />);
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- }).toThrow("Cannot read property 'world' of undefined");
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+ }).toThrow("Cannot read properties of undefined (reading 'world')");
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});
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it('should warn when class contextType is undefined', () => {
@@ -981,7 +981,7 @@ describe('ReactDOMServer', () => {
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expect(() => {
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ReactDOMServer.renderToString(<Foo />);
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- }).toThrow("Cannot read property 'world' of undefined");
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+ }).toThrow("Cannot read properties of undefined (reading 'world')");
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assertConsoleErrorDev([
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'Foo defines an invalid contextType. ' +
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'contextType should point to the Context object returned by React.createContext(). ' +
@@ -1007,7 +1007,7 @@ describe('ReactDOMServer', () => {
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expect(() => {
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ReactDOMServer.renderToString(<Foo />);
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- }).toThrow("Cannot read property 'hello' of undefined");
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+ }).toThrow("Cannot read properties of undefined (reading 'hello')");
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assertConsoleErrorDev([
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'Foo defines an invalid contextType. ' +
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'contextType should point to the Context object returned by React.createContext(). ' +
@@ -1026,7 +1026,7 @@ describe('ReactDOMServer', () => {
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expect(() => {
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ReactDOMServer.renderToString(<Foo />);
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- }).toThrow("Cannot read property 'world' of undefined");
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+ }).toThrow("Cannot read properties of undefined (reading 'world')");
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assertConsoleErrorDev([
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'Foo defines an invalid contextType. ' +
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'contextType should point to the Context object returned by React.createContext(). ' +
packages/react-reconciler/src/__tests__/ReactHooksWithNoopRenderer-test.js
+1
-1
@@ -234,7 +234,7 @@ describe('ReactHooksWithNoopRenderer', () => {
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it('throws when called outside the render phase', async () => {
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expect(() => useState(0)).toThrow(
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- "Cannot read property 'useState' of null",
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+ "Cannot read properties of null (reading 'useState')",
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);
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assertConsoleErrorDev([
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'Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for' +
scripts/jest/matchers/toThrow.js
deleted
-50
@@ -1,50 +0,0 @@
1
-'use strict';
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-
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-// V8 uses a different message format when reading properties of null or undefined.
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-// Older versions use e.g. "Cannot read property 'world' of undefined"
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-// Newer versions use e.g. "Cannot read properties of undefined (reading 'world')"
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-// This file overrides the built-in toThrow() matches to handle both cases,
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-// enabling the React project to support Node 12-16 without forking tests.
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-
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-const toThrowMatchers = require('expect/build/toThrowMatchers').default;
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-const builtInToThrow = toThrowMatchers.toThrow;
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-
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-// Detect the newer stack format:
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-let newErrorFormat = false;
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-try {
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- null.test();
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-} catch (error) {
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- if (error.message.includes('Cannot read properties of null')) {
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- newErrorFormat = true;
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- }
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-}
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-
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-// Detect the message pattern we need to rename:
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-const regex = /Cannot read property '([^']+)' of (.+)/;
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-
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-// Massage strings (written in the older format) to match the newer format
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-// if tests are currently running on Node 16+
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-function normalizeErrorMessage(message) {
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- if (newErrorFormat) {
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- const match = message.match(regex);
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- if (match) {
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- return `Cannot read properties of ${match[2]} (reading '${match[1]}')`;
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- }
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- }
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-
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- return message;
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-}
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-
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-function toThrow(value, expectedValue) {
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- if (typeof expectedValue === 'string') {
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- expectedValue = normalizeErrorMessage(expectedValue);
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- } else if (expectedValue instanceof Error) {
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- expectedValue.message = normalizeErrorMessage(expectedValue.message);
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- }
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-
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- return builtInToThrow.call(this, value, expectedValue);
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-}
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-
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-module.exports = {
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- toThrow,
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-};
scripts/jest/setupTests.js
-1
@@ -47,7 +47,6 @@ if (process.env.REACT_CLASS_EQUIVALENCE_TEST) {
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expect.extend({
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...require('./matchers/reactTestMatchers'),
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- ...require('./matchers/toThrow'),
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});
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// We have a Babel transform that inserts guards against infinite loops.
scripts/jest/spec-equivalence-reporter/setupTests.js
-1
@@ -60,5 +60,4 @@ afterEach(assertConsoleLogsCleared);
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expect.extend({
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...require('../matchers/reactTestMatchers'),
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- ...require('../matchers/toThrow'),
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});