Jest + Typescript + Absolute paths (baseUrl) gives error: Cannot find module

I was struggling with the same problem and actually it turns out that a simple change seems to do the trick.

I just updated the moduleDirectories field in jest.config.js.

Before

moduleDirectories: ['node_modules']

After

moduleDirectories: ['node_modules', 'src']

Hope it helps.

As many here pointed out moduleNameMapper in jest.config.js needs to define paths specified in tsconfig.json. For example, if you have paths in tsconfig.json defined as follows

// tsconfig.json{ ... "baseUrl": "src", "paths": {    "@alias/*": [ 'path/to/alias/*' ] } ...}

then your jest.config.js needs to provide those paths in moduleNameMapper in the following format:

// jest.config.jsmodule.exports = {    'roots': [        '<rootDir>/src'    ],    'transform': {        '^.+\\.tsx?$': 'ts-jest'    },    'moduleNameMapper': {         '@alias/(.*)': '<rootDir>/src/path/to/alias/$1'    }};

Having that we can improve our jest.config.js to convert paths defined in tsconfig.json automatically. Here is a Gist code snippet for that:

// jest.config.jsfunction makeModuleNameMapper(srcPath, tsconfigPath) {    // Get paths from tsconfig    const {paths} = require(tsconfigPath).compilerOptions;    const aliases = {};    // Iterate over paths and convert them into moduleNameMapper format    Object.keys(paths).forEach((item) => {        const key = item.replace('/*', '/(.*)');        const path = paths[item][0].replace('/*', '/$1');        aliases[key] = srcPath + '/' + path;    });    return aliases;}const TS_CONFIG_PATH = './tsconfig.json';const SRC_PATH = '<rootDir>/src';module.exports = {    'roots': [        SRC_PATH    ],    'transform': {        '^.+\\.tsx?$': 'ts-jest'    },    'moduleNameMapper': makeModuleNameMapper(SRC_PATH, TS_CONFIG_PATH)};

Here is how I got moduleNameMapper working.

With the below config in my tsconfig:

    "paths": {      "@App/*": [        "src/*"      ],      "@Shared/*": [        "src/Shared/*"      ]    },

Here's the moduleNameMapper:

"moduleNameMapper": {  "@App/(.*)": "<rootDir>/src/$1",  "@Shared/(.*)": "<rootDir>/src/Shared/$1"}