No way to watch .ts tests

[BryanCrotaz]

"scripts": {
    "build": "tsc src/index.ts",
    "dev": "tsc src/index.ts --watch",
    "test": "qunit --require ts-node/register --watch 'test/**/*-test.ts'"
  }

Easy to run typescript tests, and pretty well documented. However --watch only reruns tests when .js files change. It ignores .tsfiles.

Suggestion: watch should trigger on both ts and js files.

[Krinkle]

Thanks, I would expect that to work as-is indeed.

The code for this is in src/cli/run.js as called from bin/qunit. We currently evaluate the glob pattern during the runs (initial and re-run from watch), which means that new files matching the pattern are naturally picked up. The watcher subscribes to the working directory as a whole. The watcher does not limit itself to the glob pattern, as we want to react to changed source files as well. It ignores changes within node_modules and to non-JS files.

One way to handle this could be to remember the files list from the last run, and if the watcher tells us about a changed file in that list, always start a re-run. The downside would be that this doesn't cover .ts source files, only test files.

Another way could be to inspect require.extensions keys and take those file extensions into consideration. This would be .js and .json by default, and ts-node will have added .ts to this.

Patch welcome. I might also give it a go myself during the next release in ~12 days.