v2: Move dist dir out of .parcel-cache

[magcius]

💬 RFC

I have to clear .parcel-cache quite often to get around stale cache issues, but this wipes .parcel-cache\dist. As noted in #3407, I have set up special data inside .parcel-cache\dist so that I can test from a dev server, but this makes wiping the parcel cache quite annoying.

Currently, it is hardcoded that the dist dir is inside the cache dir: https://github.com/parcel-bundler/parcel/blob/v2/packages/reporters/dev-server/src/ServerReporter.js#L25

But this makes it hard to wipe the assets from the build without affecting the dist folder.

Alternatively, the cache folder could set things up so that it is .parcel-cache/dist and .parcel-cache/assets, and then I can simply wipe one folder.

[devongovett]

We'd like to get to the point where you never need to manually delete the cache. Any patterns of when you need to delete it?

[magcius]

I had to delete the cache pretty regularly after changing configuration. To give one example: when first trying to use Parcel 2, I got this error message:

$ D:\Development\NITRO_BMD\node_modules\.bin\parcel src\index.html
Server running at http://localhost:1234
× D:\Development\NITRO_BMD\src\main.ts: D:\Development\NITRO_BMD\src\main.ts: 'const' enums are not supported.

So I ^C parcel, and then added in a .parcelrc:

{
    "extends": "@parcel/config-default",
    "transforms": {
        "*.ts": [ "@parcel/transformer-typescript-tsc", "@parcel/transformer-js" ]
    }
}

Upon re-running Parcel, I encounter this error:

$ D:\Development\NITRO_BMD\node_modules\.bin\parcel src\index.html
Server running at http://localhost:1234
× Dependency did not resolve to an asset
    at MutableBundleGraph.createBundleGroup (D:\Development\NITRO_BMD\node_modules\@parcel\core\lib\public\MutableBundleGraph.js:69:13)
    at enter (D:\Development\NITRO_BMD\node_modules\@parcel\bundler-default\lib\DefaultBundler.js:58:41)
    at enter (D:\Development\NITRO_BMD\node_modules\@parcel\core\lib\Graph.js:475:16)
    at walk (D:\Development\NITRO_BMD\node_modules\@parcel\core\lib\Graph.js:310:26)
    at walk (D:\Development\NITRO_BMD\node_modules\@parcel\core\lib\Graph.js:331:22)
    at walk (D:\Development\NITRO_BMD\node_modules\@parcel\core\lib\Graph.js:331:22)

Wiping the .parcel-cache fixes it. I am happy to give more detailed repro instructions if necessary.

I have had to wipe the cache multiple times in the process of exploring fixes for #3690 as well.

[mischnic]

Upon re-running Parcel, I encounter this error:

(Sounds similar to this (where the cache becomes corrupt when parcel crashed because of an error or Ctrl-c): #3655)

[magcius]

The repro I posted is 100% consistent, if you are having a hard time reproducing the other issue.

[alidcast]

@devongovett Testing out Parcel 2, so I'll add - I have to delete the cache any time I make a change to a linked package.

[DeMoorJasper]

@Alidlo there's an issue to track this #4332 we're working on fixing this.

[devongovett]

The dist dir was moved out of the cache in #4519.