Clearer error message when node: null condition prevents subpath import

[IanVS]

I hit a snag when trying to bundle msw@next using tsup (which sets platform: node, apparently). It took me a while to figure out what was happening, because the error message was confusing:

✘ [ERROR] Could not resolve "msw/browser"

    lib/msw-config.ts:2:46:
      2 │ import { setupWorker, type SetupWorker } from 'msw/browser';
        ╵                                               ~~~~~~~~~~~~~

  The path "./browser" is not exported by package "msw":

    node_modules/msw/package.json:9:13:
      9 │   "exports": {
        ╵              ^

  The file "./lib/browser/index.js" is exported at path "./browser":

    node_modules/msw/package.json:21:17:
      21 │       "default": "./lib/browser/index.js"
         ╵                  ~~~~~~~~~~~~~~~~~~~~~~~~

  Import from "msw/browser" to get the file "node_modules/msw/lib/browser/index.js":

    lib/msw-config.ts:2:46:
      2 │ import { setupWorker, type SetupWorker } from 'msw/browser';
        │                                               ~~~~~~~~~~~~~
        ╵                                               "msw/browser"

  You can mark the path "msw/browser" as external to exclude it from the bundle, which will remove
  this error.

1 error

I realized eventually that this was happening because msw sets a condition of "node": null to prevent the import in node environments.

So I understand why this is happening now, but it took a while to figure it out. I think some more information in the error message would be really useful. Maybe just something simple like, The path "./browser" is not exported by package "msw", due to the "node": null condition.

[evanw]

Thanks for the report and the test case. I haven't seen packages use null in the wild before like this.