exception afer upgrading to v2

[boneskull]

I have a custom generator here.

For whatever reason, v2.0.0 of this package is causing the failure below. v1.1.1 does not exhibit this behavior.

It should be noted that the src/ dir is not where my generators live! They are transpiled by babel and put into generators/. Removing src from my files property of package.json has no effect; I still get this error.

My generator is linked to my global Node install. This is Node v8.5, yeoman v2.0.0, macOS.

/Users/boneskull/Documents/projects/generator-bonestorm/src/app/index.js:14
  constructor (args, opts) {
                           ^
TypeError: Class constructor Generator cannot be invoked without 'new'
    at new Bonestorm (/Users/boneskull/Documents/projects/generator-bonestorm/src/app/index.js:14:28)
    at Environment.instantiate (/usr/local/lib/node_modules/yo/node_modules/yeoman-environment/lib/environment.js:403:12)
    at Environment.create (/usr/local/lib/node_modules/yo/node_modules/yeoman-environment/lib/environment.js:381:17)
    at Environment.run (/usr/local/lib/node_modules/yo/node_modules/yeoman-environment/lib/environment.js:438:28)
    at env.lookup (/usr/local/lib/node_modules/yo/lib/cli.js:156:11)
    at Environment.resolver.lookup (/usr/local/lib/node_modules/yo/node_modules/yeoman-environment/lib/resolver.js:50:12)
    at init (/usr/local/lib/node_modules/yo/lib/cli.js:117:7)
    at pre (/usr/local/lib/node_modules/yo/lib/cli.js:76:3)
    at Object.<anonymous> (/usr/local/lib/node_modules/yo/lib/cli.js:205:3)
    at Module._compile (module.js:573:30)
    at Object.Module._extensions..js (module.js:584:10)
    at Module.load (module.js:507:32)
    at tryModuleLoad (module.js:470:12)
    at Function.Module._load (module.js:462:3)
    at Function.Module.runMain (module.js:609:10)
    at startup (bootstrap_node.js:158:16)

[SBoudrias]

Hey, I took a quick look and can't find anything obvious (especially that error is a bit weird).

I wonder if this could have something to do with the babel compilation result?

[boneskull]

Don’t think so... downgrading to pre-2.0.0 works fine. Can I provide more info?

[boneskull]

Oh rather that babel is choking on THIS package? hmm....

[HsuTing]

I have same problem when I upgrade to v2.x and use babel.

[HsuTing]

I know why it will throw TypeError. Owing to babel, babel will transform class to function like:

function App(args, options) {
  _classCallCheck(this, App);
  ...
}

This does not use class in node.js, but Generator is a class type in node.js. In the class which is transformed by babel, it will call a parent class as function. However, class in node.js is not a function. This is a real class type. As a result, it will throw a TypeError.

I build a temporary package with babel to support this problem: @hsuting/yeoman-generator .
Hope this will help someone who has the same problem.

[HsuTing]

I ask in babel slack and get the solution.
You can set the .babelrc as this:

{
  presets: [
    ['env', {
      targets: {
        node: true
      }
    }]
  ]
}

This will not transform class to function.
And you can extends the Generator from yeoman-generator@v2.x.

[cjam]

Ran into this same issue while using typescript (no babel). Downgrading to pre 2.x seems to have fixed it.

[christopher-taormina-zocdoc]

I've also run into the same issue, downgrading has helped me as well

[tonyhallett]

For those using typescript change your compiler options to target ES2015

[github-actions]

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