deploy doesn't clean up lib/ folder

[crapougnax]

firebase deploy --only functions (at least) doesn't clean up its built lib/ folder before building.

This is most of the time not a problem but it might become one if an incorrect named file was created then deleted after the build/deploy process ended with an error.

The built version remains in the lib/ folder and same errors are still happening.

[REQUIRED] Environment info

firebase-tools: 8.4.1

Platform: macOS

[REQUIRED] Test case

Imagine that I use a Cloud function as an API with Express. For modularity and readability, I have the following structure:

src/
   api.ts
   files/
      index.ts // this is my named exports
      create.ts
      read.ts
      update.ts
      delete.ts

And my cloud function looks like this:

import * as functions from 'firebase-functions'
import * as files from './files'
...
const app = express()
...
app.get('/file/:path', files.read)
...

Now, imagine that, in a rush, I create a files.ts in my src/folder. At the next deploy, I get the following Express error due to files.tsbeing imported instead of files/index.ts: Error: Route.get() requires a callback function but got a [object Undefined]

[REQUIRED] Expected behavior

If I remove my files.tseverything should return to normal and I should build and deploy successfully.

[REQUIRED] Actual behavior

Despite the deletion of files.ts, the lib/folder keeps track of the built files.js. And the deploy fails over and over.

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[samtstern]

@crapougnax thanks for the feedback. The Firebase CLI does not create or manage the lib folder. That's the job of tsc. I think you're invoking tsc in your functions.predeploy hook but the solution is to modify that hook to clean up the folder for you if that's the behavior you want.

You could do something as simple as rm -rf lib && tsc or use a cross-platform module like rimraf:
https://www.npmjs.com/package/rimraf