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Parcel with source maps enabled cannot import LiveScript

See original GitHub issue

🐛 bug report

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

{
  "name": "livescript-parcel",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "parcel build index.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "livescript": "^1.6.0",
    "parcel-bundler": "^1.10.3"
  }
}

🤔 Expected Behavior

import livescript from 'livescript' should work

😯 Current Behavior

 > parcel build index.js

⚠️  Could not load existing sourcemap of "node_modules/livescript/lib/index.js".
🚨  livescript-parcel/node_modules/livescript/lib/index.js:69:43: Expecting Unicode escape sequence \uXXXX (69:43)
  67 |         if ((ref$ = options.map) === 'linked' || ref$ === 'debug') {
  68 |           mapPath = path.basename(outputFilename) + ".map";
> 69 |           result.code += "\n + mapPath + "\n";
     |                                           ^
  70 |         } else {
  71 |           result.code += "\n//# sourceMappingURL=data:application/json;base64," + bufferFrom(result.map.toString()).toString('base64') + "\n";
  72 |         }

It appears that parcel is incorrectly interpreting the file as a source map.

        if ((ref$ = options.map) === 'linked' || ref$ === 'debug') {
          mapPath = path.basename(outputFilename) + ".map";
          result.code += "\n//# sourceMappingURL=" + mapPath + "\n";
        } else {
          result.code += "\n//# sourceMappingURL=data:application/json;base64," + bufferFrom(result.map.toString()).toString('base64') + "\n";
        }

💻 Code Sample

https://github.com/raine/livescript-parcel

Issue Analytics

State:
Created 5 years ago
Reactions:5
Comments:23 (8 by maintainers)

Top GitHub Comments

10reactions

arthurswcommented, Mar 21, 2020

Two fixes :

either remove \n from strings in the package sources (node_modules/paper/dist/paper-full.js in my case)
or disable source-maps: parcel index.html --no-source-maps

Is there a better solution?

9reactions

Maker-Markcommented, Jun 23, 2021

This is still an issue with 1.x.

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