Errors in moduleNameMapper configuration seemingly ignored

[p-decoraid]

Do you want to request a feature or report a bug?

Bug

What is the current behavior?

I was following https://facebook.github.io/jest/docs/tutorial-webpack.html and I had the following in my package.json:

  "jest": {
    "moduleNameMapper": {
       "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$": "/mocks/filemock.js",
            "\\.(css|less)$": "identity-obj-proxy"
    }
  },

However, I have not installed identity-obj-proxy (due to having to upgrade node from 5 to 6 for it to work).

In this configuration, running tests produces:

butler% npm test

> @ test /home/me/apps/frontend
> jest

 FAIL  library/paymentform.test.js
  ● Test suite failed to run

    /home/me/apps/frontend/library/paymentform.css:1
    ({"Object.":function(module,exports,require,__dirname,__filename,global,jest){.form-reactbuttons {
                                                                                             ^
    SyntaxError: Unexpected token .
      
      at transformAndBuildScript (node_modules/jest-runtime/build/transform.js:284:10)
      at Object. (library/paymentform.js:2:46)
      at Object. (library/paymentform.test.js:3:46)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        2.045s
Ran all test suites.
npm ERR! Test failed.  See above for more details.

I'm not 100% certain whether the "include CSS text verbatim in a JS module" is the behavior when there is no moduleNameMapper configuration at all, or it's something else, but when I installed identity-obj-proxy this error went away and the tests started running.

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal repository on GitHub that we can npm install and npm test.

I should be able to create this if necessary.

What is the expected behavior?

I expected to be told that identity-obj-proxy is missing in some fashion.

I also expected the tests to not be attempted to run at all, given that the configuration was bogus.

Run Jest again with --debug and provide the full configuration it prints. Please mention your node and npm version and operating system.

butler% ./node_modules/.bin/jest --debug
jest version = 16.0.1
test framework = jasmine2
config = {
  "moduleNameMapper": [
    [
      "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$",
      "/home/me/apps/frontend/mocks/filemock.js"
    ],
    [
      "\\.(css|less)$",
      "identity-obj-proxy"
    ]
  ],
  "rootDir": "/home/me/apps/frontend",
  "name": "-home-me-apps-frontend",
  "setupFiles": [],
  "testRunner": "/home/me/apps/frontend/node_modules/jest-jasmine2/build/index.js",
  "scriptPreprocessor": "/home/me/apps/frontend/node_modules/babel-jest/build/index.js",
  "usesBabelJest": true,
  "automock": false,
  "bail": false,
  "browser": false,
  "cacheDirectory": "/tmp/jest",
  "clearMocks": false,
  "coveragePathIgnorePatterns": [
    "/node_modules/"
  ],
  "coverageReporters": [
    "json",
    "text",
    "lcov",
    "clover"
  ],
  "globals": {},
  "haste": {
    "providesModuleNodeModules": []
  },
  "mocksPattern": "__mocks__",
  "moduleDirectories": [
    "node_modules"
  ],
  "moduleFileExtensions": [
    "js",
    "json",
    "jsx",
    "node"
  ],
  "modulePathIgnorePatterns": [],
  "noStackTrace": false,
  "notify": false,
  "preset": null,
  "preprocessorIgnorePatterns": [
    "/node_modules/"
  ],
  "resetModules": false,
  "testEnvironment": "jest-environment-jsdom",
  "testPathDirs": [
    "/home/me/apps/frontend"
  ],
  "testPathIgnorePatterns": [
    "/node_modules/"
  ],
  "testRegex": "(/__tests__/.*|\\.(test|spec))\\.jsx?$",
  "testURL": "about:blank",
  "timers": "real",
  "useStderr": false,
  "verbose": null,
  "watch": false,
  "cache": true,
  "watchman": true,
  "testcheckOptions": {
    "times": 100,
    "maxSize": 200
  }
}

butler% node -v
v6.7.0
butler% uname -a
Linux butler 4.7.0-1-amd64 #1 SMP Debian 4.7.5-1 (2016-09-26) x86_64 GNU/Linux

[ghost]

bump - same issue here - configuration almost identical to the above

[stefanfisk]

Same here, this just cost me two hours of debugging ,ó_Ò,

[thymikee]

@cpojer we should probably validate if the module passed to moduleNameMapper actually exists

[ollwenjones]

👍 Just got hung up on this (or something very similar) for a while, because I had a misspelling (styleMocks vs styleMock). It would be nice if there was some meaningful error when a moduleNameMapper pattern's file didn't resolve, rather than that pattern getting skipped.

[lindgr3n]

@thymikee Giving this a shoot.
Im guessing that in jest-resolve/src/index.js in _resolveStubModuleName() that if
this.getModule(moduleName) || Resolver.findNodeModule(moduleName, { basedir: dirname, browser: this._options.browser, extensions, moduleDirectory, paths, });
Is giving null you should provide a console.error message?

[thymikee]

@lindgr3n awesome!
Yea, I think this is a good place for this. You can throw ValidationError from jest-validate package for nicer formatting of the message. We can discuss the details after you send a PR (ideally with a test) 🙂

[lindgr3n]

Great, working on the PR.

[samsch]

I hit this issue today. Any progress on the patch?

[lindgr3n]

Have the PR here #3567 with the fix. Waiting for it to be merged.

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