React Native testing library "`render` method has not been called" occurs sporadically

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We just recently did a React Native upgrade to 0.72.4 on our project and therefore updated the versions of the testing libraries as well. These are the versions they're at right now:

Relevant dependencies:

    "jest-environment-jsdom": "29.7.0",
    "jest-expo": "49.0.0",

Relevant dev dependencies:

    "@testing-library/jest-native": "5.4.3",
    "@testing-library/react-hooks": "8.0.1",
    "@testing-library/react-native": "12.3.0",
    "jest": "29.7.0",
    "ts-jest": "29.1.1",

Our jest.config.js looks like this:

module.exports = {
  testEnvironment: 'node',
  setupFiles: [
    './jest.setup.js',
    './node_modules/react-native-gesture-handler/jestSetup.js',
    './node_modules/react-native/jest/setup.js',
    './node_modules/react-native/Libraries/Utilities/__mocks__/BackHandler.js',
  ],
  transform: {
    '^.+\\.tsx?$': [
      'ts-jest',
      {
        tsconfig: 'tsconfig.jest.json',
        babelConfig: true,
        diagnostics: {
          exclude: ['**'],
        },
      },
    ],
  },
  preset: 'jest-expo',
  setupFilesAfterEnv: ['@testing-library/jest-native/extend-expect'],
  moduleFileExtensions: ['js', 'json', 'node', 'ts', 'tsx'],
  moduleNameMapper: {
    '\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$':
      '<rootDir>/assetsTransformer.js',
    '\\.(css|less)$': '/assetsTransformer.js',
    '\\.svg': '<rootDir>/__mocks__/svgMocks.js',
    'uuid': require.resolve('uuid'),
  },
  transformIgnorePatterns: [
    'node_modules/(?!(jest-)?@react-native|react-native|@react-native-community|@react-navigation|expo(nent)?|@expo(nent)?/.*)',
  ],
  roots: ['<rootDir>/__mocks__', '<rootDir>/src'],
  collectCoverageFrom: [
    '!src/core/**/**.js',
    '!src/api',
    '!src/constants',
    '!src/navigation',
    '!node_modules/',
    '!src/index.js',
    'src/**/*.{js,jsx,ts,tsx}',
    '!src/**/stories.{js,jsx,ts,tsx}',
    '!src/**/styles.{js,jsx,ts,tsx}',
    '!src/**/types.{js,jsx,ts,tsx}',
  ],
  coverageThreshold: {
    global: {
      branches: 30,
      functions: 30,
      lines: 30,
      statements: 30,
    },
  },
};

We do have a custom render wrapper function that looks like this:

import React, { ReactElement } from 'react';

import { render, act } from '@testing-library/react-native';
import configureStore from 'redux-mock-store';

import AppProviders from 'core/providers';
import { RootState } from 'core/store';

type Props = {
  initialState?: Partial<RootState>;
  hideGlobalConfirm?: boolean;
  mockStore?: boolean;
};

const middlewares: any = [];
const mockStore = configureStore(middlewares);

const customRender = (ui: ReactElement, options?: Omit<any, 'queries'> & Props) =>
  render(ui, {
    wrapper: ({ children }) => {
      if (options?.mockStore) {
        const store = mockStore(options?.initialState);
        return (
          <AppProviders store={store} hideGlobalConfirm={options?.hideGlobalConfirm}>
            {children}
          </AppProviders>
        );
      }
      return (
        <AppProviders initialState={options?.initialState as any} hideGlobalConfirm={options?.hideGlobalConfirm}>
          {children}
        </AppProviders>
      );
    },
    ...options,
  });

export async function wait(ms = 1000) {
  await act(async () => {
    return new Promise((resolve) => {
      setTimeout(resolve, ms);
    });
  });
}

export * from '@testing-library/react-native';

export { customRender };

The problem is that the tests fail at random with the error 'render' method has not been called. And it's a different test each time. An example of a test that fails is:

describe('renders correctly', () => {
    it('should be able to render - default', async () => {
      const wrapper = customRender(renderComponent());
      const myComponent = await wrapper.findByTestId('myComponent');
      expect(myComponent).toBeDefined();
      expect(wrapper.toJSON()).toMatchSnapshot();
    });
  });

Any idea what might be happening here? The tests were working fine before we did the upgrade.

0

There are 0 answers