Unit test fails when a library is imported locally

[Overdrivr]

Version

2.9.3

Reproduction link

https://gitlab.com/cronobo/vue-e2e-test

Steps to reproduce

1. Scaffold app
2. Install a library (I tried with vue-octicon and vue-ionicons)
3. Import locally this lib into HelloWorld component
4. npm run dev works fine, icon is rendered
5. Yet, npm run unit crashes with a weird SyntaxError

What is expected?

No SyntaxError, since html was not even modified

What is actually happening?

> jest --config test/unit/jest.conf.js --coverage

● Deprecation Warning:

  Option "mapCoverage" has been removed, as it's no longer necessary.

  Please update your configuration.

  Configuration Documentation:
  https://facebook.github.io/jest/docs/configuration.html

 FAIL  test\unit\specs\HelloWorld.spec.js
  ● Test suite failed to run

    C:\Users\remib\Gitlab\vue-e2e-test\node_modules\vue-ionicons\dist\md-alert.vue:1
    ({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){<template>
                                                                                             ^

    SyntaxError: Unexpected token <

       6 |       <li>
       7 |         <a
    >  8 |           href="https://vuejs.org"
       9 |           target="_blank"
      10 |         >
      11 |           Core Docs

      at ScriptTransformer._transformAndBuildScript (node_modules/jest-runtime/build/script_transformer.js:316:17)
      at src/components/HelloWorld.vue:8:68
      at Object.<anonymous> (src/components/HelloWorld.vue:106:3)

Running coverage on untested files...Failed to collect coverage from C:\Users\remib\Gitlab\vue-e2e-test\src\components\HelloWorld.vue
ERROR: Cannot read property 'fileCoverage' of undefined
STACK: TypeError: Cannot read property 'fileCoverage' of undefined
    at Instrumenter.instrumentSync (C:\Users\remib\Gitlab\vue-e2e-test\node_modules\istanbul-lib-instrument\dist\instrumenter.js:148:40)
    at exports.default (C:\Users\remib\Gitlab\vue-e2e-test\node_modules\jest\node_modules\jest-cli\build\generate_empty_coverage.js:18:18)
    at Object.worker (C:\Users\remib\Gitlab\vue-e2e-test\node_modules\jest\node_modules\jest-cli\build\reporters\coverage_worker.js:48:84)
    at execMethod (C:\Users\remib\Gitlab\vue-e2e-test\node_modules\jest-worker\build\child.js:92:29)
    at process.on (C:\Users\remib\Gitlab\vue-e2e-test\node_modules\jest-worker\build\child.js:42:7)
    at emitTwo (events.js:126:13)
    at process.emit (events.js:214:7)
    at emit (internal/child_process.js:772:12)
    at _combinedTickCallback (internal/process/next_tick.js:141:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)
----------|----------|----------|----------|----------|-------------------|
File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
----------|----------|----------|----------|----------|-------------------|
All files |  Unknown |  Unknown |  Unknown |  Unknown |                   |
----------|----------|----------|----------|----------|-------------------|
Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        3.719s
Ran all test suites.

[UrsMetz]

Maybe this is caused by vuejs/vue-jest#45?

[Overdrivr]

I will try with mocha to check if this comes from jest or not. Keep you posted

[LinusBorg]

This is an issue with the webpack template, not vue-cli