parcel: Basic .parcelrc crashes Parcel

Using scopehoisting requires that “@parcel/transformer-js” transforms the assets (and set some metadata). The only thing we can do here is give a better error message. You should use a ˚.parcelrc` like this one:

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

I too got the error The expression evaluated to a falsy value and tried to add this as my .parcelrc, but it doesn’t work:

{ [Error: Invalid Parcel Config]
  diagnostics:
   [ { message: 'Invalid Parcel Config',
       origin: '@parcel/core',
       filePath: '.parcelrc',
       language: 'json',
       codeFrame: [Object] } ],
  name: 'Error' }

For me, it seems like updating from beta-3.1 to the latest nightly (2.0.0-nightly.688) fixed the issue.

I have this issue in the latest nightlies of Parcel 2. Not in the alpha/beta.

> parcel build public/index.html

🚨 Build failed.
@parcel/packager-js: The expression evaluated to a falsy value:

  (0, _assert().default)(typeof assetId === 'string')

AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:

  (0, _assert().default)(typeof assetId === 'string')

    at ScopeHoistingPackager.resolveSymbol (/Users/me/me/myproject/portal/node_modules/@parcel/packager-js/lib/ScopeHoistingPackager.js:685:27)
    at ScopeHoistingPackager.buildReplacements (/Users/me/me/myproject/portal/node_modules/@parcel/packager-js/lib/ScopeHoistingPackager.js:594:27)
    at ScopeHoistingPackager.buildAsset (/Users/me/me/myproject//portal/node_modules/@parcel/packager-js/lib/ScopeHoistingPackager.js:414:39)
    at ScopeHoistingPackager.visitAsset (/Users/me/me/myproject/portal/node_modules/@parcel/packager-js/lib/ScopeHoistingPackager.js:369:17)
    at /Users/me/me/myproject/node_modules/@parcel/packager-js/lib/ScopeHoistingPackager.js:204:40
    at enter (/Users/me/me/myproject/portal/node_modules/@parcel/core/lib/Graph.js:543:16)
    at enter (/Users/me/me/myproject/portal/node_modules/@parcel/core/lib/Graph.js:543:16)
    at enter (/Users/me/me/myproject/portal/node_modules/@parcel/core/lib/Graph.js:543:16)
    at walk (/Users/me/me/myproject/portal/node_modules/@parcel/core/lib/Graph.js:403:26)
    at walk (/Users/me/me/myproject/portal/node_modules/@parcel/core/lib/Graph.js:425:22)

Adding --no-scope-hoisting to the build command fixes but is not ideal.

My .parcelrc looks like this:

{
  "extends": "@parcel/config-default",
  "transformers": {
    "*.{ts,tsx}": ["@parcel/transformer-typescript-tsc"],
    "*.{jpg,png,svg}": ["@parcel/transformer-raw"]
  }
}

using

    "@parcel/transformer-raw": "^2.0.0-beta.2",
    "@parcel/transformer-typescript-tsc": "^2.0.0-beta.2",
    "parcel": "^2.0.0-nightly.676",

@hegner123 in your case, it’s because you’re using @babel/preset-env instead of @parcel/babel-preset-env (https://v2.parceljs.org/languages/babel/#extending-the-default-babel-config), which is bad for bundle size anyway.

The underlying problem is that using require instead of ESM imports for css files is broken (and in this case, Babel transpiles import "./App.css" into require). Does that explain/help fix the error for anyone else as well?

I seem to be having the same behaviour as well using latest nightlies as well as beta-3.1.

@parcel/packager-js: The expression evaluated to a falsy value:

  (0, _assert().default)(typeof assetId === 'string')

AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:

  (0, _assert().default)(typeof assetId === 'string')

With or without a .parcelrc I still get the same error. Adding --no-scope-hoist also appears to be the only workaround I can currently find.

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

(I’m leaving this ticket open because of The only thing we can do here is give a better error message.)