parcel build works, but parcel watch and parcel serve fail.

[drewolson]

🐛 bug report

I'm using parcel to build a site with an HTML entry point. It requires a javascript file generated by the PureScript compiler. This whole setup worked fine with parcel 1 and correctly builds with parcel 2:

$ npx parcel build public/index.html 
✨ Built in 3.75s

dist/index.html                  878 B    337ms
dist/favicon.6b361303.ico        318 B      9ms
dist/index.479febd2.js       662.61 KB    3.01s

However, if I try to serve or watch, I get the following error:

$ npx parcel watch public/index.html
⠙ Building index.html...
thread '<unnamed>' panicked at 'index out of bounds: the len is 0 but the index is 0', /Users/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/swc_ecma_transforms_react-0.46.1/src/refresh/mod.rs:594:54
🚨 Build failed.

@parcel/transformer-js: index out of bounds: the len is 0 but the index is 0

  Error: index out of bounds: the len is 0 but the index is 0
  at Object.transform (/<project-path>/node_modules/@parcel/transformer-js/lib/JSTransformer.js:365:31)
  at async Transformation.runTransformer (/<project-path>/node_modules/@parcel/core/lib/Transformation.js:617:5)
  at async Transformation.runPipeline (/<project-path>/node_modules/@parcel/core/lib/Transformation.js:366:36)
  at async Transformation.runPipelines (/<project-path>/node_modules/@parcel/core/lib/Transformation.js:244:40)
  at async Transformation.run (/<project-path>/node_modules/@parcel/core/lib/Transformation.js:170:19)
  at async Child.handleRequest (/<project-path>/node_modules/@parcel/workers/lib/child.js:217:9)

🎛 Configuration (.babelrc, package.json, cli command)

package.json:

{
  "scripts": {
    "test": "spago -c skip test && purs-tidy check 'src/**/*.purs' 'test/**/*.purs'",
    "format": "purs-tidy format-in-place 'src/**/*.purs' 'test/**/*.purs'",
    "prod": "rm -rf dist && spago build && parcel build --no-source-maps public/index.html"
  },
  "devDependencies": {
    "parcel": "^2.0",
    "purescript": "^0.14",
    "purs-tidy": "^0.5.4",
    "react": "^17.0",
    "react-dom": "^17.0",
    "spago": "^0.20"
  }
}

🤔 Expected Behavior

parcel watch and parcel serve work, just as parcel build does.

😯 Current Behavior

parcel watch and parcel serve fail, but parcel build works.

💁 Possible Solution

Unsure.

🔦 Context

💻 Code Sample

🌍 Your Environment

$ node --version
v16.11.0
$ npm --version
8.0.0

[devongovett]

Seems like possibly a bug in SWC's react refresh transform. Do you have a code sample that can reproduce this?

[drewolson]

This is the simplest reproduction I could come up with https://github.com/drewolson/parcel-purescript

[mischnic]

This is indeed caused by the React Refresh transform. Minimal reproduction:

createElement();

swc-project/swc#2492