Vue-cli: VueCLI forces Jest's testMatch option

[Ldoppea]

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 [email protected]. 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

[laander]

Just want to add that besides package.json, we should also respect options set in jest.config.js 👌

[robcresswell]

What makes this slightly worse is that the forced option isn't even a superset of Jests own default. For example, when testing with other Vue applications I've always just suppled a test.js file in the same directory as the component it's testing (less directory hopping, encourages testing at same time as component design, file name is self explanatory, etc.)

For example, I tend to use something like:

src/components/my-component
├── index.js
├── my-component.vue
└── test.js

With Vue CLI, this doesn't work at all, which I'd consider a regression. Is there any technical reason to force override Jests own default?

[posva]

I think it's easier to just remove that code from the cli runtime and move it to the config generated by the cli

[robcresswell]

That sounds like a sensible solution to me 😇

[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)

[laander]

Much better solution @dhensche ! 🤘
An added benefit is that other tooling (e.g. the Jest extension for VSCode) works out of the box.

[Ldoppea]

Thank you @dhensche 👍