Error on import module to test in Jest

[X] Bug
[ ] Build issue
[ ] Feature request

Version info

Angular: 7
Angular CLI: 7.3.1
countup.js-angular2:  7.1.1
Jest: 24.5.0

Description

Hi, I’m having an issue to run tests with Jest in a component that I’m using the lib. The error log from Jest is described below. Can you help me? Thanks.

src/app/components/limit-bar/limit-bar.component.spec.ts ● Test suite failed to run

Jest encountered an unexpected token

This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

Here's what you can do:
 • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
 • If you need a custom transformation specify a "transform" option in your config.
 • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper"

config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/en/configuration.html

Details:

C:\Development\neon-pj\node_modules\countup.js\dist\countUp.min.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){var __assign=this&&this.__assign||function(){return(__assign=Object.assign||function(t){for(var i,a=1,s=arguments.length;a<s;a++)for(var n in i=arguments[a])Object.prototype.hasOwnProperty.call(i,n)&&(t[n]=i[n]);return t}).apply(this,arguments)},CountUp=function(){function t(t,i,a){var s=this;this.target=t,this.endVal=i,this.options=a,this.version="2.0.4",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:""},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.count=function(t){s.startTime||(s.startTime=t);var i=t-s.startTime;s.remaining=s.duration-i,s.useEasing?s.countDown?s.frameVal=s.startVal-s.easingFn(i,0,s.startVal-s.endVal,s.duration):s.frameVal=s.easingFn(i,s.startVal,s.e

SyntaxError: Unexpected token export

  at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:451:17)
  at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:493:19)
  at Object.<anonymous>.__assign (node_modules/countup.js-angular2/bundles/countup.js-angular2.umd.js:2:111)
  at Object.<anonymous> (node_modules/countup.js-angular2/bundles/countup.js-angular2.umd.js:5:2)

[inorganik]

Ok, I got it working. Also I pushed up my changes in the test app included in this repo, so it has a passing test with Jest, as well as a new section in the README.

For Jest, make sure you have the following in your jest.config.js:

transform: {
  '^.+\\.(js|ts|tsx)$': 'ts-jest'
},
transformIgnorePatterns: ['node_modules/(?!countup.js)']

Also! In your root tsconfig.json, add

    "allowJs": true,

under compilerOptions

[inorganik]

I was able to reproduce, I’ll see what I can figure out