CODEWITHSUNDEEP
reactjsjestjs
dragonfly
dragonfly

Reputation: 17783

Two modules with the same name - mocking issue

In jest config setup.js, I mock two modules:

jest.mock('somePath1/Translator');
jest.mock('somePath2/Translator');

When running tests I get this:

jest-haste-map: duplicate manual mock found:
  Module name: Translator
  Duplicate Mock path: C:\XXX\dev\YYY\src\components\ZZZ\services\__mocks__\Translator.js
This warning is caused by two manual mock files with the same file name.
Jest will use the mock file found in:
C:\XXX\dev\YYY\src\components\ZZZ\services\__mocks__\Translator.js
 Please delete one of the following two files:
 C:\XXX\dev\YYY\src\common\services\__mocks__\Translator.js
C:\XXX\dev\YYY\src\components\ZZZ\services\__mocks__\Translator.js

However, both are needed, some tests use service from once locations, other from the second.

How can I fix it?

Upvotes: 5

Views: 1783

Answers (2)

Alberto S.
Alberto S.

Reputation: 2115

I was having the same issue since I have multiple modules with the same name, but on different paths under /src/.

jest-haste-map: duplicate manual mock found: fetch.service
  The following files share their name; please delete one of them:
    * <rootDir>/src/modules/order/__mocks__/fetch.service.ts
    * <rootDir>/src/modules/restaurant/__mocks__/fetch.service.ts

After some research, I updated the jest.config.ts so it includes:

modulePathIgnorePatterns: ["<rootDir>/.*/__mocks__"]

this change made the warning to dissapear :9

Upvotes: 5

Alec1017
Alec1017

Reputation: 119

you could try using a beforeEach() and calling jest.resetModules() from inside it. Then just mock your dependency on a test by test basis:

describe("some test", () => {
    beforeEach(() => {
       jest.resetModules();
    });

    test("Some test", () => {
        jest.mock("somePath1/Translator");
        // run tests here
    });

    test("Some other test", () => {
        jest.mock("somePath2/Translator");
        // run tests here
    });
});

This will clear your mocks before each test so you shouldn't have any collisions with file names.

Upvotes: -1

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