jest-mock-axios

library4.9.0jsnpmunverified

Lightweight, synchronous Axios mock for unit testing with Jest, version 4.9.0. It provides a simple API to mock Axios requests and responses, enabling synchronous test execution without waiting for real HTTP calls. Unlike other mocking libraries, it works synchronously, making tests easier to read and write. It requires a manual Jest mock setup and primarily supports Jest. Note: v4.6.0 was inadvertently a pure ES module causing issues; v4.6.1 and later fix this. The library ships TypeScript types.

testing

npm install jest-mock-axios

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · JEST-MOCK-AXIOS

jest-mock-axios

testingjavascriptv4.9.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import mockAxios from 'jest-mock-axios';

✗ const mockAxios = require('jest-mock-axios');

The default export is the mock object. CommonJS require works but is not recommended in ES module projects. The library is ESM-first since v4.6.1.

mockAxios

✓ import mockAxios from 'jest-mock-axios';

✗ import { mockAxios } from 'jest-mock-axios';

The mock is a default export, not a named export. Named import will result in undefined.

Type imports (TypeScript)

✓ import mockAxios from 'jest-mock-axios';

No separate type import needed; types are included in the default export. Use `import type { MockAxios } from 'jest-mock-axios'` if you need the type explicitly.

Sets up a manual Jest mock for axios and shows a basic test that resolves a request synchronously with mockAxios.mockResponse.

// __mocks__/axios.js import mockAxios from 'jest-mock-axios'; export default mockAxios; // myComponent.test.js import mockAxios from 'jest-mock-axios'; import myComponent from './myComponent'; // Mock axios before imports in test jest.mock('axios'); afterEach(() => { mockAxios.reset(); }); it('should resolve with data', () => { const onResponse = jest.fn(); const onError = jest.fn(); myComponent.fetchData().then(onResponse).catch(onError); // Simulate a successful response mockAxios.mockResponse({ data: { users: [] } }); expect(onResponse).toHaveBeenCalledWith({ data: { users: [] } }); expect(onError).not.toHaveBeenCalled(); });

Debug

Known issues

breakingIn v4.6.0 the module was inadvertently a pure ES module, causing CommonJS projects to break. Importing or requiring fails with ERR_REQUIRE_ESM.

fix

Use v4.5.0 or upgrade to v4.6.1+.

affects: 4.6.0

deprecatedThe methods `lastReqGet` and `lastPromiseGet` are deprecated in favor of newer API (though still available). Their return structure may change.

fix

Migrate to using `mockAxios.getReqByMatchUrl` or `mockAxios.lastPromiseGet` with caution; prefer using request handler callback.

affects: >=4.0.0

gotchaThe mock must be set up as a manual Jest mock in `__mocks__/axios.js`. Simply importing `jest-mock-axios` without this setup will not intercept axios calls.

fix

Create `__mocks__/axios.js` as shown in the README and call `jest.mock('axios')` in your test file before importing the module under test.

affects: all

gotchaUsing `mockAxios.mockResponse` or `mockError` after the promise settles will have no effect. The mock works synchronously, so you must call mock methods before the next tick.

fix

Ensure you call `mockAxios.mockResponse` or `mockError` immediately after triggering the axios call, within the same synchronous test block.

affects: all

gotchaThe mock does not support mocking axios `CancelToken` or interceptors out of the box. Attempting to use these features will lead to unexpected behavior.

fix

Use a more comprehensive mock or manually mock interceptors if needed. Consider libraries like `axios-mock-adapter` for more advanced scenarios.

affects: all

Errors

Common errors & fixes

Cannot find module 'axios' from '__mocks__/axios.js'

The mock file is not placed correctly or jest.mock('axios') is not called, so Jest cannot resolve the manual mock.

fix

Ensure you have a `__mocks__` folder at the project root (or inside `src` if using react-scripts) and that you call `jest.mock('axios')` in your test file.

TypeError: mockAxios.mockResponse is not a function

The mock was not set up correctly; the import likely returned the real axios or undefined.

fix

Verify you created `__mocks__/axios.js` with `export default mockAxios` and that you import `mockAxios` from `jest-mock-axios` inside that file.

Jest encountered an unexpected token - SyntaxError: Cannot use import statement outside a module

The `jest-mock-axios` package uses ESM, but your project is configured to use CommonJS (e.g., older Jest config or no transformIgnorePatterns adjustment).

fix

Add `transformIgnorePatterns: ['node_modules/(?!(jest-mock-axios)/)']` to Jest config, or use a version that ships both CJS and ESM (v4.6.1+).

Cannot read property 'then' of undefined

The axios method (e.g., `post`) returned undefined because the mock wasn't ready when the call was made.

fix

Make sure you called `jest.mock('axios')` before importing your module under test, and that the mock file exports the mock axios instance.

Upgrade

Version history

4.9.0latest on npm

Audit

Dependencies

axiosrequiredMocks the axios library; users must have axios installed

Agent activity

11 hits · last 30 days

node

Resources

githubhttps://github.com/knee-cola/jest-mock-axios ↗

packagejest-mock-axios ↗

homepagehttps://github.com/knee-cola/jest-mock-axios#readme ↗