VueCLI forces Jest's testMatch option

Version

3.0.0-beta.6

Reproduction link

https://github.com/Ldoppea/vue-cli-jest-testmatch

Steps to reproduce

Init project with following options :

Vue CLI v3.0.0-beta.6
? Please pick a preset: Manually select features
? Check the features needed for your project: Unit
? Pick a unit testing solution: Jest
? Where do you prefer placing config for Babel, PostCSS, ESLint, etc.? In package.json
? Save this as a preset for future projects? (Y/n) n

Move /tests/unit/HelloWorld.spec.js in /src/components/

Add testMatch in package.json Jest category :

    "testMatch": [
      "test/**/*.spec.js", 
      "src/**/*.spec.js"
    ]

Run npm run test

What is expected?

HelloWorld.spec.js should be tested

What is actually happening?

No test is found by Jest. Get the following error :

No tests found
In D:\Work\test\vue\testJest
  6 files checked.
  testMatch: D:\Work\test\vue\testJest\(tests\unit\**\*.spec.(ts|tsx|js)|**\__tests__\*.(ts|tsx|js)) - 0 matches
  testPathIgnorePatterns: \\node_modules\\ - 6 matches
Pattern:  - 0 matches
 ERROR  jest exited with code 1.

testMatch still has the value forced by vueCLI

---

I was able to run my tests from src folder and without using testMatch on vueCLI@3.0.0-beta.4. This commit changed the test detection behavior : https://github.com/vuejs/vue-cli/commit/2c61d236d77dfcb22b4560afe4c957ddf45b4337#diff-17aae08cfc13cba07661681220ddd985 (I do not use typescript)

[dhensche]

It appears that the plugin always sets the testMatch to [`--testMatch`, `<rootDir>/(tests/unit/**/*.spec.(ts|tsx|js)|**/__tests__/*.(ts|tsx|js))`] if none is specified via a command line argument, instead of respecting anything set in package.json. If we would like to respect those configurations, it appears to be an easy enough tweak I would gladly contribute

[dhensche]

With my current PR (#1069) that is what I ended up doing. I moved the testMatch pattern over to the generator so that it goes into the package.json or jest.config.js (depending on how the user wants their config files laid out)