Migrating to v2

[BrandonALittle]

The documentation for migration from v1 to v2 does not explain how to migrate. There are major differences in config between the two, especially when using the API in a script, but I can't find any explanation about how the configuration for v2 is different from v1.

Could you please update your docs with information that would help someone to migrate?

[mischnic]

You mean https://v2.parceljs.org/getting-started/migration/?

configuration for v2 is different from v1

What exactly do you mean by configuration?

[BrandonALittle]

I'm seeing a lot of issues with tilde ~ module resolution, but I noticed a comment in the docs referencing an issue with that 'paths' property in tsconfig. Is the tilde altogether prohibited with v2 when using the @parcel/transformer-typescript-tsc?

[BrandonALittle]

I managed to get the bundler to run without error, but it doesn't seem to be bundling my node modules. In v1 there was a config option to enable this, but in v2 I don't see a way to do the same. I tried activating the bundle analyzer as described here: https://v2.parceljs.org/features/production/ but that's not working as expected either. I'm still working on it...

[mischnic]

The tilde might point to a different folder now: https://v2.parceljs.org/features/module-resolution/#tilde-paths

but it doesn't seem to be bundling my node modules

Are you intentionally bundling for Node? If not, do you have engines: {node: ...} in your package.json or main: "index.js"?
Otherwise: there's includeNodeModules in the target options: https://v2.parceljs.org/configuration/package-json/#includenodemodules

I tried activating the bundle analyzer as described here: v2.parceljs.org/features/production but that's not working as expected either

What have you tried but didn't work?

[BrandonALittle]

Yes, I'm intentionally building for Node. I did have the engines: {node: ...}, and tried removing that without success. I do not have a targets entry anywhere, so I'm just wondering why that is necessary with v2 but not v1.

As far as the bundle analyzer, I added the environment variable as instructed at the Production page, but there's no output. I suspect it's just failing before getting to that point.

[mischnic]

Yes, I'm intentionally building for Node

Then having the engines is fine.

I do not have a targets entry anywhere, so I'm just wondering why that is necessary with v2 but not v1.

You can also pass targets via the API: https://v2.parceljs.org/plugin-system/api/#InitialParcelOptions.
With V1, bundleNodeModules was a global option, now it was renamed and moved to the target specific options. Something like

targets: {
  "default": {
     "includeNodeModules": true
  }
}

should work.

As far as the bundle analyzer, I added the environment variable as instructed at the Production page, but there's no output. I suspect it's just failing before getting to that point.

That is printed on the buildSuccess, so if you get a build error before that, there will be no report.

[BrandonALittle]

Sorry for the delay. Using the example snippet with the addition of the distDir, I managed to get the bundle to build. But two issues remain:

1. I expected the v2 bundle to be smaller than the v1 bundle, but that is not the case. Perhaps tree-shaking is not enabled?
2. I am not getting any output from the bundle-analyzer, and no parce-bundle-reports folder is being generated.

[BrandonALittle]

I am currently passing scopeHoist: false in the options, so it looks like that disables tree-shaking. Changing this option to true results in a JS Heap out of memory error.

[BrandonALittle]

Resolved by changing version of Node from v10 to v14