Typescript: Typescript Watch - Cleaning Target Files on Source Deletion

[alohaninja]

Can we add a compiler option to also glob-delete a target file when the source file is removed? We run into this constantly and have to gulp clean frequently - it makes the usage of tsc -watch pointless as we have to constantly purge the output directory.

[mhegazy]

For tsc --watch we have a list of output files from the previous iteration, we just need to diff that with the current list, and delete the old outputs.

[timm-gs]

Is there a recommended way to work around this today? We have prepended rimraf lib/ to our build scripts, which removes the folder containing the compiled JS files.

But this is caused problems with sym-linked modules. The importing project's watch then gets broken with TS2307: Cannot find module, as it only seem to register the disappearance of the lib folder, but not the new one put in its place.

[admosity]

Can someone provide some pointers where I can help implement this? @mhegazy?

[mhegazy]

Things have gotten a bit more complicated with the addition of the Builder the and the WatchProgram (see https://github.com/Microsoft/TypeScript/pull/20234), there is not really a place to keep this information, since it is always partial, and we are not rebuilding the information after every change as we used to do. I suppose we could investigate restarting the builder if a file was removed. but we will need a way to detect that in the first place..

[bes]

Hi!

This is constantly biting us during development. A file is removed - but nightwatch / some other library still picks it up and runs tests based on code that should not be there.

Last activity on this was more than 8 months ago, but I hope there is still a possibility for this to be added?

Thanks!

[nullxone]

If you're using jest, you can use ts-jest

[TarVK]

My 'solution' is obviously not the full thing that is trying to be implemented right now, it's just some very basic behavior I need myself, But I think it might help some people that need something like this right now. So if it's alright, I will just leave a link here for now: https://www.npmjs.com/package/ts-cleaner

[beverts312]

This functionality would also be helpful on a simple --clean, this is effecting us in CI and when switching between branches locally

[insidewhy]

ts-cleaner didn't work for me, so I wrote ts-purify. It works exactly the same way as ts-cleaner but uses fb-watchman (its only dependency) instead of chokidar. This makes it very small and very efficient at watching, but on the other hand, you'll need to install watchman to use it.

[geremy22]

Hello!!
I solved this issue with watch, diff-file-tree and rimraf:
tsconfig.json

{
  "compileOnSave": false,
  "compilerOptions": {
    "rootDir": "./src",
    "outDir": "./.tmp",
    "preserveSymlinks": true,
    "sourceMap": true,
    "declaration": true,
    "module": "umd",
    "moduleResolution": "node",
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "target": "es6",
    "typeRoots": [
      "node_modules/@types"
    ],
    "lib": [
      "es6"
    ]
  },
  "include": [
    "./src/**/*.*"
  ]
}

package.json

{
  "name": "diff-tree",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "build": "tsc && npm run build:copy",
    "build:copy": "node -e \"(d = require('diff-file-tree')).diff('./.tmp', './dist').then((ch)=>d.applyRight('./.tmp', './dist', ch)).finally(()=>process.exit(0));\" && rimraf ./.tmp",
    "watch": "watch \"npm run build\" ./src --interval 1 --wait 0.1"
  },
  "author": "",
  "license": "ISC",
  "devDpendencies": {
    "diff-file-tree": "^2.3.2",
    "rimraf": "^3.0.0",
    "typescript": "^3.6.4",
    "watch": "^1.0.2"
  }
}

[whitecolor]

For cleaning up of not actual compilation results I use this https://github.com/whitecolor/ts-clean-built