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Jest has problems with the IIFE module of dist/capacitor.js

See original GitHub issue

Description of the problem: Testing a compontent or service that uses a Plugin with Jest fails with following message:

 ● Test suite failed to run

    TypeError: Cannot read property 'App' of undefined

      22 | import { StorageSelectors } from "../store/storage.selectors";
      23 | 
    > 24 | const { App, Device, Browser } = Plugins;
         |         ^
      25 | 
      26 | @Injectable({
      27 |     providedIn: "root"

Affected platform

Android
iOS
electron
web
testing with jest

OS of the development machine

Windows
macOS
linux

Other information: I am using a NX workspace. Versions:

@nrwl/schematics: 7.8.6
jest: 24.8.0
jest-preset-angular: 7.1.1

As mentioned in issue https://github.com/ionic-team/stencil/issues/1234 the problem seems to be that the capacitor.js module (the IIFE module in the dist folder) doesn’t export anything. (module.exports never gets written)

Capacitor version: 1.0.0-beta.25

node version: 6.8.0

npm version: 10.15.1

CocoaPods version: N/A

Steps to reproduce:

Run npx create-nx-workspace capacitor-reproduce
- SCSS
- some npm scope
- an empty workspace
Run cd capacitor-reproduce\
Run npm install --save @capacitor/core @capacitor/cli
Run npx cap init
- App
- com.example.app
- npm
Run ng g application example
- Angular
- default folder (just press enter)
- Jest
- Protractor
- app
Edit the file apps/example/src/app/app.component.ts a. Add import { Plugins } from '@capacitor/core' and const { Device } = Plugins;
Run ng test
- The before mentioned error happens here

Link to sample project: https://github.com/WoMayr/reproduce-jest-capacitor

Issue Analytics

State:
Created 4 years ago
Comments:14 (11 by maintainers)

Top GitHub Comments

1reaction

WoMayrcommented, May 22, 2019

If I understood the rollup config correctly, @capacitor/core only gets compiled for IIFE which is not a CommonJS format and not usable in NodeJS applications (like Jest). An alternative would be to bundle capacitor as an UMD module which works with Jest (I tested this with the current master) and should theoretically also work in a browser. (http://rollupjs.org/guide/en/#output-format)

0reactions

jcesarmobilecommented, Jun 17, 2019

It was fixed after the final release, so should be good on next release.

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