chore: ESLint 9 (#1728)

.codecov.yml

@@ -3,6 +3,9 @@ coverage:
   round: down
   range: 70...100
   status:
+    patch:
+      default:
+        target: 80% # Required patch coverage target
     project:
       default:
         threshold: 0.5%  # Allowable coverage drop in percentage points

.eslintignore

@@ -1,6 +0,0 @@
-flow-typed/
-build/
-experiments-rtl/
-website/
-
-jest-setup.ts

.eslintrc

@@ -1,15 +0,0 @@
-{
-  "extends": "@callstack",
-  "rules": {
-    "no-console": 1,
-    // Ignore certain webpack alias because it can't be resolved
-    "import/no-unresolved": [2, { "ignore": ["^@theme", "^@docusaurus", "^@generated"] }],
-    "react/no-multi-comp": 0,
-    "react-native/no-color-literals": "off",
-    "react-native/no-inline-styles": "off",
-    "react-native/no-raw-text": 0,
-    "react-native-a11y/has-valid-accessibility-descriptors": "off",
-    "react-native-a11y/has-valid-accessibility-ignores-invert-colors": 0,
-    "react-native-a11y/has-valid-accessibility-value": "off"
-  }
-}

eslint.config.mjs

@@ -0,0 +1,35 @@
+import tseslint from 'typescript-eslint';
+import callstackConfig from '@callstack/eslint-config/react-native.flat.js';
+
+export default [
+  {
+    ignores: [
+      'flow-typed/',
+      'build/',
+      'experiments-rtl/',
+      'website/',
+      'eslint.config.mjs',
+      'jest-setup.ts',
+    ],
+  },
+  ...callstackConfig,
+  ...tseslint.configs.strict,
+  {
+    rules: {
+      'no-console': 'error',
+    },
+  },
+  {
+    files: ['**/*.test.{ts,tsx}', 'src/test-utils/**'],
+    rules: {
+      'react/no-multi-comp': 'off',
+      'react-native/no-color-literals': 'off',
+      'react-native/no-inline-styles': 'off',
+      'react-native/no-raw-text': 'off',
+      'react-native-a11y/has-valid-accessibility-descriptors': 'off',
+      'react-native-a11y/has-valid-accessibility-ignores-invert-colors': 'off',
+      'react-native-a11y/has-valid-accessibility-value': 'off',
+      '@typescript-eslint/no-explicit-any': 'off',
+    },
+  },
+];

package.json

@@ -73,7 +73,7 @@
     "@babel/preset-typescript": "^7.26.0",
     "@callstack/eslint-config": "^15.0.0",
     "@react-native/babel-preset": "0.77.0-rc.0",
-    "@release-it/conventional-changelog": "^9.0.2",
+    "@release-it/conventional-changelog": "^10.0.0",
     "@relmify/jest-serializer-strip-ansi": "^1.0.2",
     "@types/jest": "^29.5.14",
     "@types/react": "^18.3.12",
@@ -81,8 +81,7 @@
     "babel-jest": "^29.7.0",
     "babel-plugin-module-resolver": "^5.0.2",
     "del-cli": "^6.0.0",
-    "eslint": "^8.57.1",
-    "eslint-plugin-prettier": "^4.2.1",
+    "eslint": "^9.17.0",
     "flow-bin": "~0.170.0",
     "jest": "^29.7.0",
     "prettier": "^2.8.8",
@@ -90,8 +89,8 @@
     "react-native": "0.77.0-rc.0",
     "react-test-renderer": "18.3.1",
     "release-it": "^18.0.0",
-    "strip-ansi": "^6.0.1",
-    "typescript": "^5.6.3"
+    "typescript": "^5.6.3",
+    "typescript-eslint": "^8.19.1"
   },
   "publishConfig": {
     "registry": "https://registry.npmjs.org"

src/__tests__/__snapshots__/render-debug.test.tsx.snap

@@ -288,6 +288,7 @@ exports[`debug with only props from TextInput components 1`] = `
 exports[`debug: another custom message 1`] = `
 "another custom message
 
+
 <View>
   <Text>
     Is the banana fresh?
@@ -370,6 +371,7 @@ exports[`debug: another custom message 1`] = `
 exports[`debug: with message 1`] = `
 "my custom message
 
+
 <View>
   <Text>
     Is the banana fresh?

src/__tests__/auto-cleanup-skip.test.tsx

@@ -4,6 +4,7 @@ import { View } from 'react-native';
 let render: (element: React.ReactElement) => void;
 beforeAll(() => {
   process.env.RNTL_SKIP_AUTO_CLEANUP = 'true';
+  // eslint-disable-next-line @typescript-eslint/no-require-imports
   const rntl = require('..');
   render = rntl.render;
 });

src/__tests__/cleanup.test.tsx

@@ -1,4 +1,3 @@
-/* eslint-disable react/no-multi-comp */
 import * as React from 'react';
 import { View } from 'react-native';
 import { cleanup, render } from '../pure';

src/__tests__/questionsBoard.test.tsx

@@ -4,7 +4,7 @@ import { render, screen, userEvent } from '..';
 
 type QuestionsBoardProps = {
   questions: string[];
-  onSubmit: (obj: {}) => void;
+  onSubmit: (obj: object) => void;
 };
 
 jest.useFakeTimers();

src/__tests__/render-debug.test.tsx

@@ -1,6 +1,5 @@
 import * as React from 'react';
 import { Pressable, Text, TextInput, View } from 'react-native';
-import stripAnsi from 'strip-ansi';
 import { configure, fireEvent, render, screen } from '..';
 import { logger } from '../helpers/logger';
 
@@ -98,9 +97,9 @@ test('debug', () => {
   screen.debug({ message: 'another custom message' });
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
-  expect(stripAnsi(mockCalls[1][0] + mockCalls[1][1])).toMatchSnapshot('with message');
-  expect(stripAnsi(mockCalls[2][0] + mockCalls[2][1])).toMatchSnapshot('another custom message');
+  expect(mockCalls[0][0]).toMatchSnapshot();
+  expect(`${mockCalls[1][0]}\n${mockCalls[1][1]}`).toMatchSnapshot('with message');
+  expect(`${mockCalls[2][0]}\n${mockCalls[2][1]}`).toMatchSnapshot('another custom message');
 
   const mockWarnCalls = jest.mocked(logger.warn).mock.calls;
   expect(mockWarnCalls[0]).toMatchInlineSnapshot(`
@@ -117,9 +116,7 @@ test('debug changing component', () => {
   screen.debug();
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot(
-    'bananaFresh button message should now be "fresh"',
-  );
+  expect(mockCalls[0][0]).toMatchSnapshot('bananaFresh button message should now be "fresh"');
 });
 
 test('debug with only children prop', () => {
@@ -127,7 +124,7 @@ test('debug with only children prop', () => {
   screen.debug({ mapProps: () => ({}) });
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
+  expect(mockCalls[0][0]).toMatchSnapshot();
 });
 
 test('debug with only prop whose value is bananaChef', () => {
@@ -145,7 +142,7 @@ test('debug with only prop whose value is bananaChef', () => {
   });
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
+  expect(mockCalls[0][0]).toMatchSnapshot();
 });
 
 test('debug with only props from TextInput components', () => {
@@ -155,7 +152,7 @@ test('debug with only props from TextInput components', () => {
   });
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
+  expect(mockCalls[0][0]).toMatchSnapshot();
 });
 
 test('debug should use debugOptions from config when no option is specified', () => {
@@ -169,7 +166,7 @@ test('debug should use debugOptions from config when no option is specified', ()
   screen.debug();
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
+  expect(mockCalls[0][0]).toMatchSnapshot();
 });
 
 test('filtering out props through mapProps option should not modify component', () => {
@@ -190,5 +187,5 @@ test('debug should use given options over config debugOptions', () => {
   screen.debug({ mapProps: (props) => props });
 
   const mockCalls = jest.mocked(logger.info).mock.calls;
-  expect(stripAnsi(mockCalls[0][0])).toMatchSnapshot();
+  expect(mockCalls[0][0]).toMatchSnapshot();
 });

src/__tests__/render.test.tsx

@@ -1,4 +1,3 @@
-/* eslint-disable no-console */
 import * as React from 'react';
 import { Pressable, Text, TextInput, View } from 'react-native';
 import { fireEvent, render, RenderAPI, screen } from '..';

src/__tests__/wait-for.test.tsx

@@ -19,7 +19,7 @@ class Banana extends React.Component<any> {
   }
 }
 
-class BananaContainer extends React.Component<{}, any> {
+class BananaContainer extends React.Component<object, any> {
   state = { fresh: false };
 
   onChangeFresh = async () => {
@@ -196,7 +196,7 @@ test.each([false, true])(
 
 const blockThread = (timeToBlockThread: number, legacyFakeTimers: boolean) => {
   jest.useRealTimers();
-  let end = Date.now() + timeToBlockThread;
+  const end = Date.now() + timeToBlockThread;
 
   while (Date.now() < end) {
     // do nothing

src/act.ts

@@ -8,6 +8,7 @@ type ReactAct = 0 extends 1 & typeof React.act ? typeof reactTestRendererAct : t
 
 // See https://github.com/reactwg/react-18/discussions/102 for more context on global.IS_REACT_ACT_ENVIRONMENT
 declare global {
+  // eslint-disable-next-line no-var
   var IS_REACT_ACT_ENVIRONMENT: boolean | undefined;
 }
 
@@ -45,13 +46,11 @@ function withGlobalActEnvironment(actImplementation: ReactAct) {
               // eslint-disable-next-line promise/always-return
               (returnValue) => {
                 setIsReactActEnvironment(previousActEnvironment);
-                // @ts-expect-error
-                resolve(returnValue);
+                resolve(returnValue as never);
               },
               (error) => {
                 setIsReactActEnvironment(previousActEnvironment);
-                // @ts-expect-error
-                reject(error);
+                reject(error as never);
               },
             );
           },
@@ -69,7 +68,7 @@ function withGlobalActEnvironment(actImplementation: ReactAct) {
   };
 }
 
-// @ts-expect-error
+// @ts-expect-error: typings get too complex
 const act = withGlobalActEnvironment(reactAct) as ReactAct;
 
 export default act;

src/helpers/errors.ts

@@ -1,6 +1,7 @@
 import prettyFormat from 'pretty-format';
 
 export class ErrorWithStack extends Error {
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
   constructor(message: string | undefined, callsite: Function) {
     super(message);
     if (Error.captureStackTrace) {
@@ -32,6 +33,7 @@ export const prepareErrorMessage = (
   return errorMessage;
 };
 
+// eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
 export const createQueryByError = (error: unknown, callsite: Function): null => {
   if (error instanceof Error) {
     if (error.message.includes('No instances found')) {
@@ -41,9 +43,7 @@ export const createQueryByError = (error: unknown, callsite: Function): null =>
   }
 
   throw new ErrorWithStack(
-    // generic refining of `unknown` is very hard, you cannot do `'toString' in error` or anything like that
-    // Converting as any with extra safe optional chaining will do the job just as well
-    `Query: caught unknown error type: ${typeof error}, value: ${(error as any)?.toString?.()}`,
+    `Query: caught unknown error type: ${typeof error}, value: ${error}`,
     callsite,
   );
 };

src/helpers/logger.ts

@@ -4,28 +4,28 @@ import chalk from 'chalk';
 import redent from 'redent';
 
 export const logger = {
-  debug(message: any, ...args: any[]) {
+  debug(message: unknown, ...args: unknown[]) {
     const output = formatMessage('●', message, ...args);
     nodeConsole.debug(chalk.dim(output));
   },
 
-  info(message: any, ...args: any[]) {
+  info(message: unknown, ...args: unknown[]) {
     const output = formatMessage('●', message, ...args);
     nodeConsole.info(output);
   },
 
-  warn(message: any, ...args: any[]) {
+  warn(message: unknown, ...args: unknown[]) {
     const output = formatMessage('▲', message, ...args);
     nodeConsole.warn(chalk.yellow(output));
   },
 
-  error(message: any, ...args: any[]) {
+  error(message: unknown, ...args: unknown[]) {
     const output = formatMessage('■', message, ...args);
     nodeConsole.error(chalk.red(output));
   },
 };
 
-function formatMessage(symbol: string, message: any, ...args: any[]) {
+function formatMessage(symbol: string, message: unknown, ...args: unknown[]) {
   const formatted = nodeUtil.format(message, ...args);
   const indented = redent(formatted, 4);
   return `  ${symbol} ${indented.trimStart()}\n`;

src/helpers/object.ts

@@ -1,4 +1,4 @@
-export function pick<T extends {}>(object: T, keys: (keyof T)[]): Partial<T> {
+export function pick<T extends object>(object: T, keys: (keyof T)[]): Partial<T> {
   const result: Partial<T> = {};
   keys.forEach((key) => {
     if (object[key] !== undefined) {

src/helpers/timers.ts

@@ -64,7 +64,7 @@ function getFakeTimersConfigFromType(type: FakeTimersTypes) {
 const jestFakeTimersAreEnabled = (): boolean => Boolean(getJestFakeTimersType());
 
 // we only run our tests in node, and setImmediate is supported in node.
-function setImmediatePolyfill(fn: Function) {
+function setImmediatePolyfill(fn: () => void) {
   return globalObj.setTimeout(fn, 0);
 }
 

src/index.ts

@@ -10,7 +10,6 @@ if (!process?.env?.RNTL_SKIP_AUTO_CLEANUP) {
   // if you don't like this then either import the `pure` module
   // or set the RNTL_SKIP_AUTO_CLEANUP env variable to 'true'.
   if (typeof afterEach === 'function') {
-    // eslint-disable-next-line no-undef
     afterEach(async () => {
       await flushMicroTasks();
       cleanup();

src/matchers/__tests__/to-contain-element.test.tsx

@@ -123,7 +123,7 @@ test('toContainElement() handles non-element element', () => {
   const view = screen.getByTestId('view');
 
   expect(() =>
-    // @ts-expect-error
+    // @ts-expect-error: intentionally passing wrong element shape
     expect(view).not.toContainElement({ name: 'non-element' }),
   ).toThrowErrorMatchingInlineSnapshot(`
     "expect(received).not.toContainElement()

src/matchers/__tests__/utils.test.tsx

@@ -4,7 +4,7 @@ import { render, screen } from '../..';
 import { checkHostElement, formatElement } from '../utils';
 
 function fakeMatcher() {
-  // Do nothing.
+  return { pass: true, message: () => 'fake' };
 }
 
 test('formatElement', () => {
@@ -15,7 +15,7 @@ test('checkHostElement allows host element', () => {
   render(<View testID="view" />);
 
   expect(() => {
-    // @ts-expect-error
+    // @ts-expect-error: intentionally passing wrong element shape
     checkHostElement(screen.getByTestId('view'), fakeMatcher, {});
   }).not.toThrow();
 });
@@ -24,14 +24,14 @@ test('checkHostElement allows rejects composite element', () => {
   render(<View testID="view" />);
 
   expect(() => {
-    // @ts-expect-error
+    // @ts-expect-error: intentionally passing wrong element shape
     checkHostElement(screen.UNSAFE_root, fakeMatcher, {});
   }).toThrow(/value must be a host element./);
 });
 
 test('checkHostElement allows rejects null element', () => {
   expect(() => {
-    // @ts-expect-error
+    // @ts-expect-error: intentionally passing wrong element shape
     checkHostElement(null, fakeMatcher, {});
   }).toThrowErrorMatchingInlineSnapshot(`
     "expect(received).fakeMatcher()

src/matchers/types.ts

@@ -279,14 +279,16 @@ export interface JestNativeMatchers<R> {
 
 // Implicit Jest global `expect`.
 declare global {
+  // eslint-disable-next-line @typescript-eslint/no-namespace
   namespace jest {
-    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    // eslint-disable-next-line @typescript-eslint/no-empty-object-type, @typescript-eslint/no-unused-vars
     interface Matchers<R, T = {}> extends JestNativeMatchers<R> {}
   }
 }
 
 // Explicit `@jest/globals` `expect` matchers.
-// @ts-ignore
+// @ts-expect-error: Invalid module name in augmentation, module '@jest/expect' cannot be found
 declare module '@jest/expect' {
+  // eslint-disable-next-line @typescript-eslint/no-empty-object-type
   interface Matchers<R extends void | Promise<void>> extends JestNativeMatchers<R> {}
 }

src/native-state.ts

@@ -11,7 +11,7 @@ export type NativeState = {
   contentOffsetForElement: WeakMap<ReactTestInstance, Point>;
 };
 
-export let nativeState: NativeState = {
+export const nativeState: NativeState = {
   valueForElement: new WeakMap(),
   contentOffsetForElement: new WeakMap(),
 };

src/queries/unsafe-props.ts

@@ -3,10 +3,10 @@ import prettyFormat from 'pretty-format';
 import { ErrorWithStack, prepareErrorMessage } from '../helpers/errors';
 import { createQueryByError } from '../helpers/errors';
 
-const UNSAFE_getByProps = (
-  instance: ReactTestInstance,
-): ((props: { [propName: string]: any }) => ReactTestInstance) =>
-  function getByPropsFn(props: { [propName: string]: any }) {
+type Props = Record<string, unknown>;
+
+const UNSAFE_getByProps = (instance: ReactTestInstance): ((props: Props) => ReactTestInstance) =>
+  function getByPropsFn(props: Props) {
     try {
       return instance.findByProps(props);
     } catch (error) {
@@ -16,8 +16,8 @@ const UNSAFE_getByProps = (
 
 const UNSAFE_getAllByProps = (
   instance: ReactTestInstance,
-): ((props: { [propName: string]: any }) => Array<ReactTestInstance>) =>
-  function getAllByPropsFn(props: { [propName: string]: any }) {
+): ((props: Props) => Array<ReactTestInstance>) =>
+  function getAllByPropsFn(props: Props) {
     const results = instance.findAllByProps(props);
     if (results.length === 0) {
       throw new ErrorWithStack(
@@ -30,8 +30,8 @@ const UNSAFE_getAllByProps = (
 
 const UNSAFE_queryByProps = (
   instance: ReactTestInstance,
-): ((props: { [propName: string]: any }) => ReactTestInstance | null) =>
-  function queryByPropsFn(props: { [propName: string]: any }) {
+): ((props: Props) => ReactTestInstance | null) =>
+  function queryByPropsFn(props: Props) {
     try {
       return UNSAFE_getByProps(instance)(props);
     } catch (error) {
@@ -40,10 +40,8 @@ const UNSAFE_queryByProps = (
   };
 
 const UNSAFE_queryAllByProps =
-  (
-    instance: ReactTestInstance,
-  ): ((props: { [propName: string]: any }) => Array<ReactTestInstance>) =>
-  (props: { [propName: string]: any }) => {
+  (instance: ReactTestInstance): ((props: Props) => Array<ReactTestInstance>) =>
+  (props: Props) => {
     try {
       return UNSAFE_getAllByProps(instance)(props);
     } catch {
@@ -53,10 +51,10 @@ const UNSAFE_queryAllByProps =
 
 // Unsafe aliases
 export type UnsafeByPropsQueries = {
-  UNSAFE_getByProps: (props: { [key: string]: any }) => ReactTestInstance;
-  UNSAFE_getAllByProps: (props: { [key: string]: any }) => Array<ReactTestInstance>;
-  UNSAFE_queryByProps: (props: { [key: string]: any }) => ReactTestInstance | null;
-  UNSAFE_queryAllByProps: (props: { [key: string]: any }) => Array<ReactTestInstance>;
+  UNSAFE_getByProps: (props: Props) => ReactTestInstance;
+  UNSAFE_getAllByProps: (props: Props) => Array<ReactTestInstance>;
+  UNSAFE_queryByProps: (props: Props) => ReactTestInstance | null;
+  UNSAFE_queryAllByProps: (props: Props) => Array<ReactTestInstance>;
 };
 
 // TODO: migrate to makeQueries pattern

src/queries/unsafe-type.ts

@@ -3,10 +3,13 @@ import * as React from 'react';
 import { ErrorWithStack, prepareErrorMessage } from '../helpers/errors';
 import { createQueryByError } from '../helpers/errors';
 
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export type UnsafeComponentType = React.ComponentType<any>;
+
 const UNSAFE_getByType = (
   instance: ReactTestInstance,
-): ((type: React.ComponentType<any>) => ReactTestInstance) =>
-  function getByTypeFn(type: React.ComponentType<any>) {
+): ((type: UnsafeComponentType) => ReactTestInstance) =>
+  function getByTypeFn(type: UnsafeComponentType) {
     try {
       return instance.findByType(type);
     } catch (error) {
@@ -16,8 +19,8 @@ const UNSAFE_getByType = (
 
 const UNSAFE_getAllByType = (
   instance: ReactTestInstance,
-): ((type: React.ComponentType<any>) => Array<ReactTestInstance>) =>
-  function getAllByTypeFn(type: React.ComponentType<any>) {
+): ((type: UnsafeComponentType) => Array<ReactTestInstance>) =>
+  function getAllByTypeFn(type: UnsafeComponentType) {
     const results = instance.findAllByType(type);
     if (results.length === 0) {
       throw new ErrorWithStack('No instances found', getAllByTypeFn);
@@ -27,8 +30,8 @@ const UNSAFE_getAllByType = (
 
 const UNSAFE_queryByType = (
   instance: ReactTestInstance,
-): ((type: React.ComponentType<any>) => ReactTestInstance | null) =>
-  function queryByTypeFn(type: React.ComponentType<any>) {
+): ((type: UnsafeComponentType) => ReactTestInstance | null) =>
+  function queryByTypeFn(type: UnsafeComponentType) {
     try {
       return UNSAFE_getByType(instance)(type);
     } catch (error) {
@@ -37,8 +40,8 @@ const UNSAFE_queryByType = (
   };
 
 const UNSAFE_queryAllByType =
-  (instance: ReactTestInstance): ((type: React.ComponentType<any>) => Array<ReactTestInstance>) =>
-  (type: React.ComponentType<any>) => {
+  (instance: ReactTestInstance): ((type: UnsafeComponentType) => Array<ReactTestInstance>) =>
+  (type: UnsafeComponentType) => {
     try {
       return UNSAFE_getAllByType(instance)(type);
     } catch {

src/render-act.ts

@@ -10,10 +10,10 @@ export function renderWithAct(
 
   // This will be called synchronously.
   void act(() => {
-    // @ts-expect-error TestRenderer.create is not typed correctly
+    // @ts-expect-error `TestRenderer.create` is not typed correctly
     renderer = TestRenderer.create(component, options);
   });
 
-  // @ts-ignore act is synchronous, so renderer is already initialized here
+  // @ts-expect-error: `act` is synchronous, so `renderer` is already initialized here
   return renderer;
 }

src/render-hook.tsx

@@ -10,6 +10,7 @@ export type RenderHookResult<Result, Props> = {
 
 export type RenderHookOptions<Props> = {
   initialProps?: Props;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   wrapper?: ComponentType<any>;
 };
 

src/render.tsx

@@ -19,8 +19,9 @@ import { getQueriesForElement } from './within';
 export interface RenderOptions {
   /**
    * Pass a React Component as the wrapper option to have it rendered around the inner element. This is most useful for creating
-   *  reusable custom render functions for common data providers.
+   * reusable custom render functions for common data providers.
    */
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   wrapper?: React.ComponentType<any>;
 
   /**
@@ -73,23 +74,21 @@ function renderWithStringValidation<T>(
   component: React.ReactElement<T>,
   options: Omit<RenderOptions, 'unstable_validateStringsRenderedWithinText'> = {},
 ) {
-  let renderer: ReactTestRenderer;
   const { wrapper: Wrapper, ...testRendererOptions } = options ?? {};
 
-  const handleRender: React.ProfilerOnRenderCallback = (_, phase) => {
-    if (renderer && phase === 'update') {
-      validateStringsRenderedWithinText(renderer.toJSON());
-    }
-  };
-
   const wrap = (element: React.ReactElement) => (
     <Profiler id="renderProfiler" onRender={handleRender}>
       {Wrapper ? <Wrapper>{element}</Wrapper> : element}
     </Profiler>
   );
 
-  renderer = renderWithAct(wrap(component), testRendererOptions);
+  const handleRender: React.ProfilerOnRenderCallback = (_, phase) => {
+    if (renderer && phase === 'update') {
+      validateStringsRenderedWithinText(renderer.toJSON());
+    }
+  };
 
+  const renderer: ReactTestRenderer = renderWithAct(wrap(component), testRendererOptions);
   validateStringsRenderedWithinText(renderer.toJSON());
 
   return buildRenderResult(renderer, wrap);

src/user-event/event-builder/base.ts

@@ -1,7 +1,7 @@
 import { BaseSyntheticEvent } from 'react';
 
 /** Builds base syntentic event stub, with prop values as inspected in RN runtime. */
-export function baseSyntheticEvent(): Partial<BaseSyntheticEvent<{}, unknown, unknown>> {
+export function baseSyntheticEvent(): Partial<BaseSyntheticEvent<object, unknown, unknown>> {
   return {
     currentTarget: {},
     target: {},

src/user-event/setup/setup.ts

@@ -169,7 +169,7 @@ function createInstance(config: UserEventConfig): UserEventInstance {
  * @see https://github.com/testing-library/user-event/blob/7a305dee9ab833d6f338d567fc2e862b4838b76a/src/setup/setup.ts#L121
  */
 function wrapAndBindImpl<
-  Args extends any[],
+  Args extends never[],
   Impl extends (this: UserEventInstance, ...args: Args) => Promise<unknown>,
 >(instance: UserEventInstance, impl: Impl) {
   function method(...args: Args) {

src/user-event/utils/__tests__/wait.test.ts

@@ -28,26 +28,24 @@ describe('wait()', () => {
     expect(advanceTimers).toHaveBeenCalledWith(100);
   });
 
-  it('wait with null delay does not wait with real timers', async () => {
+  it('wait with undefined delay does not wait with real timers', async () => {
     jest.spyOn(globalThis, 'setTimeout');
     const advanceTimers = jest.fn();
 
-    // @ts-expect-error
-    await wait({ delay: null, advanceTimers });
+    await wait({ advanceTimers });
 
     expect(globalThis.setTimeout).not.toHaveBeenCalled();
     expect(advanceTimers).not.toHaveBeenCalled();
   });
 
   it.each(['modern', 'legacy'])(
-    'wait with null delay does not wait with %s fake timers',
+    'wait with undefined delay does not wait with %s fake timers',
     async (type) => {
       jest.useFakeTimers({ legacyFakeTimers: type === 'legacy' });
       jest.spyOn(globalThis, 'setTimeout');
       const advanceTimers = jest.fn();
 
-      // @ts-expect-error
-      await wait({ delay: null, advanceTimers });
+      await wait({ advanceTimers });
 
       expect(globalThis.setTimeout).not.toHaveBeenCalled();
       expect(advanceTimers).not.toHaveBeenCalled();

src/user-event/utils/wait.ts

@@ -1,8 +1,11 @@
-import { UserEventConfig } from '../setup';
+type WaitConfig = {
+  delay?: number;
+  advanceTimers: (delay: number) => Promise<void> | void;
+};
 
-export function wait(config: UserEventConfig, durationInMs?: number) {
+export function wait(config: WaitConfig, durationInMs?: number) {
   const delay = durationInMs ?? config.delay;
-  if (typeof delay !== 'number') {
+  if (typeof delay !== 'number' || delay == null) {
     return;
   }
 

src/wait-for.ts

@@ -43,7 +43,6 @@ function waitForInternal<T>(
       // infinite loop. However, eslint isn't smart enough to know that we're
       // setting finished inside `onDone` which will be called when we're done
       // waiting or when we've timed out.
-      // eslint-disable-next-line no-unmodified-loop-condition
       let fakeTimeRemaining = timeout;
       while (!finished) {
         if (!jestFakeTimersAreEnabled()) {
@@ -82,7 +81,6 @@ function waitForInternal<T>(
         // to resolve before continuing. We don't need to take advantage
         // of parallelization so we're fine.
         // https://stackoverflow.com/a/59243586/971592
-        // eslint-disable-next-line no-await-in-loop
         await flushMicroTasks();
       }
     } else {
@@ -127,10 +125,9 @@ function waitForInternal<T>(
       try {
         const result = expectation();
 
-        // @ts-ignore result can be a promise
-        // eslint-disable-next-line promise/prefer-await-to-then
+        // @ts-expect-error result can be a promise
         if (typeof result?.then === 'function') {
-          const promiseResult: Promise<T> = result as any;
+          const promiseResult: Promise<T> = result as unknown as Promise<T>;
           promiseStatus = 'pending';
           // eslint-disable-next-line promise/catch-or-return, promise/prefer-await-to-then
           promiseResult.then(