Jest-preset-angular: When running with "npm test" get error: Cannot find module 'core-js/es6/reflect' from 'setupJest.js'

[tijlreynhout]

When running with npm test i get the following error

FAIL src/tests/DoSomething.test.ts
● Test suite failed to run

Cannot find module 'core-js/es6/reflect' from 'setupJest.js'

  at Resolver.resolveModule (node_modules/jest-resolve/build/index.js:203:17)
  at Object.<anonymous> (node_modules/jest-preset-angular/setupJest.js:3:1)

Test Suites: 1 failed, 1 total
Tests: 0 total
Snapshots: 0 total
Time: 1.956s
Ran all test suites.
npm ERR! Test failed. See above for more details.

[wtho]

Can you check if you have core-js in your package.json in dependencies? A newly generated Angular project should have it. After npm install there obviously should be a node_modules/core-js as well. Check if it contains es6/reflect.

Also your versions of

• core-js
• Angular
• jest-preset-angular
• jest
  might be helpful to solve this.

[tijlreynhout]

this is my package.json

{
  "name": "testApp",
  "version": "0.0.1",
  "author": "Ionic Framework",
  "homepage": "http://ionicframework.com/",
  "private": true,
  "scripts": {
    "start": "ionic-app-scripts serve",
    "clean": "ionic-app-scripts clean",
    "build": "ionic-app-scripts build",
    "lint": "ionic-app-scripts lint",
    "test": "jest",
    "test:watch": "jest --watch",
    "test:ci": "jest --runInBand"
  },
  "dependencies": {
    "@angular/animations": "5.2.11",
    "@angular/common": "5.2.11",
    "@angular/compiler": "5.2.11",
    "@angular/compiler-cli": "5.2.11",
    "@angular/core": "5.2.11",
    "@angular/forms": "5.2.11",
    "@angular/http": "5.2.11",
    "@angular/platform-browser": "5.2.11",
    "@angular/platform-browser-dynamic": "5.2.11",
    "@ionic-native/core": "~4.18.0",
    "@ionic-native/file": "^4.18.0",
    "@ionic-native/splash-screen": "~4.18.0",
    "@ionic-native/status-bar": "~4.18.0",
    "@ionic/storage": "2.2.0",
    "@types/jest": "^24.0.0",
    "cordova-android": "7.0.0",
    "cordova-plugin-device": "^2.0.2",
    "cordova-plugin-file": "^6.0.1",
    "cordova-plugin-ionic-keyboard": "^2.1.3",
    "cordova-plugin-ionic-webview": "^3.1.1",
    "cordova-plugin-splashscreen": "^5.0.2",
    "cordova-plugin-statusbar": "^2.4.2",
    "cordova-plugin-whitelist": "^1.3.3",
    "ionic-angular": "3.9.2",
    "ionicons": "3.0.0",
    "jest": "^24.1.0",
    "jest-preset-angular": "^6.0.2",
    "rxjs": "5.5.11",
    "sw-toolbox": "3.6.0",
    "zone.js": "0.8.29"
  },
  "devDependencies": {
    "@ionic/app-scripts": "3.2.1",
    "@ionic/lab": "1.0.20",
    "typescript": "~2.6.2"
  },
  "jest": {
    "preset": "jest-preset-angular",
    "setupFilesAfterEnv": ["<rootDir>/src/setupJest.ts"]
  },
  "description": "An Ionic project",
  "cordova": {
    "plugins": {
      "cordova-plugin-file": {},
      "cordova-plugin-whitelist": {},
      "cordova-plugin-statusbar": {},
      "cordova-plugin-device": {},
      "cordova-plugin-splashscreen": {},
      "cordova-plugin-ionic-webview": {
        "ANDROID_SUPPORT_ANNOTATIONS_VERSION": "27.+"
      },
      "cordova-plugin-ionic-keyboard": {}
    },
    "platforms": [
      "android"
    ]
  }
}

but didn't find core-js in my node modules. It is an ionic project. But don't think that should matte?

[wtho]

A newly created ionic project should include core-js as dependency, as can be seen in a new project created using the ionic cli and ionic start myapp blank.

Just go ahead and add it to your project using npm install --save-dev core-js.

Please close this issue if this solved your problem.

Cheers!

[tijlreynhout]

it solved the first issue but now i get this:

Cannot find module './jestGlobalMocks' from 'setupJest.ts'

  1 | import 'jest-preset-angular';
> 2 | import './jestGlobalMocks';
    | ^

  at Resolver.resolveModule (node_modules/jest-resolve/build/index.js:203:17)
  at Object.<anonymous> (src/setupJest.ts:2:1)

Test Suites: 1 failed, 1 total
Tests: 0 total
Snapshots: 0 total
Time: 2.426s
Ran all test suites.
npm ERR! Test failed. See above for more details.

[wtho]

Please read the instruction in our README.md, especially about Usage and Troubleshooting before opening an issue here. Your second issue is documented there.

[theAndrewCline]

I am having the same issue regarding core-js

I attempted to install core-js manually and it did not solve my issue.

I am working with Ionic as well (version 3.9.3).

Angular version: 5.2.11
core-js version: 3.9.3
Jest version: 24.5.0
jest-preset-angular version: 7.0.1

[wtho]

What do you mean by 'the same issue'?
Do you not have core-js installed either? How do you have the version 3.9.3?

If setupJest or jestGlobalMocks is missing, make sure you setup the preset as described in our README.md.

[lonix1]

@theAndrewCline I have the same problem too though I'm not using ionic. I'm using nx. The package is definitely installed (version "^3.0.0").

How did you solve this?

[wtho]

core-js@3 had a major API change. There are no imports available through core-js/es6 anymore.

Please see https://github.com/zloirock/core-js/blob/master/docs/2019-03-19-core-js-3-babel-and-a-look-into-the-future.md for more information.

A fix is to lock core-js down to v2 or to adjust the imports.

We have not upgraded jest-preset-angular yet, feel free to open a PR if you want to help out.

[wtho]

Ok, I see, it is actually an issue on our end. I created a new issue regarding it.

See #244 for further discussion.

[lonix1]

@wtho Thanks for looking into this, it took forever to find my way to this issue, so confusing...

[theAndrewCline]

What do you mean by 'the same issue'?
Do you not have core-js installed either? How do you have the version 3.9.3?

If setupJest or jestGlobalMocks is missing, make sure you setup the preset as described in our README.md.

I made a typo, I have 3.0.0

[theAndrewCline]

I installed version 2 of core-js and tests are running normally now.