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Parcel 2: Expected constructor errors when building or watching

See original GitHub issue

Expected constructor errors when building or watching

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

package.json

    "babel-eslint": "10.0.1",
    "babel-preset-airbnb": "3.2.0",
    "babel-loader": "8.0.5",
    "babel-plugin-lodash": "3.3.4",
    "parcel": "2.0.0-alpha.1.1",

// ...
  "browser": "target/assets/main.js",
  "scripts": {
    "dev": "parcel watch app/assets/js/main.js",
    "build": "parcel build app/assets/js/main.js",
  }

babel.config.js

module.exports = function(api) {
  // Cache results until NODE_ENV changes
  api.cache.using(() => process.env.NODE_ENV);

  return {
    "presets": ["@babel/preset-env"],
    "plugins": ["@babel/plugin-syntax-dynamic-import", "lodash"]
  };
};

🤔 Expected Behavior

Build happens successfully

😯 Current Behavior

➜  play-app-template git:(feature/parcel) ✗ npm run build

> APP_NAME@1.0.0-SNAPSHOT build /home/adamwilliams/Documents/Projects/play-app-template
> parcel build app/assets/js/main.js

/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:197
        throw new Error(`Expected constructor ${value.$$type} to be registered with serializer to deserialize`);
        ^

Error: Expected constructor 2.0.0-alpha.1.1:NodeFS to be registered with serializer to deserialize
    at value (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:197:15)
    at memoizedFn (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:83:13)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:112:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:138:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:197
        throw new Error(`Expected constructor ${value.$$type} to be registered with serializer to deserialize`);
        ^

Error: Expected constructor 2.0.0-alpha.1.1:NodeFS to be registered with serializer to deserialize
    at value (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:197:15)
    at memoizedFn (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:83:13)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:112:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:138:9)
    at processKey (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:108:20)
    at walk (/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:146:9)
/home/adamwilliams/Documents/Projects/play-app-template/node_modules/@parcel/core/node_modules/@parcel/utils/lib/serializer.js:197
        throw new Error(`Expected constructor ${value.$$type} to be registered with serializer to deserialize`);

🔦 Context

Can’t use Parcel.

🌍 Your Environment

Software	Version(s)
Parcel	2.0.0-alpha.1.1
Node	v10.15.2
npm/Yarn	6.10.3
Operating System	Ubuntu 19.04

Issue Analytics

State:
Created 4 years ago
Reactions:4
Comments:10 (4 by maintainers)

Top GitHub Comments

1reaction

shanehandleycommented, Dec 12, 2019

I’ve updated to latest parcel2 and am trying to build but have a lot of babel issues to work through…I’ll try to come back to this over the next few days.

1reaction

shanehandleycommented, Sep 1, 2019

Interesting - I have been using npm and the result seems to be different when using yarn - It looks like the reporter was also using npm - I will play around with this a little today.

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