Update to babel 7 ?

[Jule-]

Is there any plan to update aurelia-cli to babel 7 soon?

It seems that these 2 requires messed transpilation when we want to use new babel version:

cli/lib/project.js

Lines 207 to 218 in 15b1f1f

	function installBabel() {
	require('babel-polyfill');
	require('babel-register')({
	plugins: [
	'transform-es2015-modules-commonjs'
	],
	ignore: (filename) => {
	let relativeFromProjectRoot = path.relative(this.directory, filename);
	return !/^aurelia_project/.test(relativeFromProjectRoot);
	}
	});
	}

And it seems that this transformation do the trick:

function installBabel() {
  require('@babel/polyfill');
  require('@babel/register')({
    plugins: [
      '@babel/plugin-transform-modules-commonjs'
    ],
    ignore: [(filename) => {
      let relativeFromProjectRoot = path.relative(this.directory, filename);
      return !/^aurelia_project/.test(relativeFromProjectRoot);
    }]
  });
}

This will allow us to use improvements of @babel/preset-env in a local .babelrc file.

[Alexander-Taran]

Would you like to provide a pull request for it @Jule- ?

[Jule-]

Yes if nothing is already planned. Maybe tomorrow.

[arabsight]

babel 7 is still in beta

[Jule-]

Indeed but at least I want to migrate to new babel repo (@babel/*), removing warnings, and maybe wait for the release before switching to babel 7?

[bigopon]

Babel 7 has several upgrades, regard to spec changes. One of that is the decorator proposal spec upgrade. Aurelia current decorator implementation is based on old version of that, and probably won't work well together with Babel 7. I'm not sure what our strategy towards this change is @EisenbergEffect

[EisenbergEffect]

A couple of weeks ago there was a meeting with Yahuda, who is working on the decorators spec, and the major framework leaders. I'm completely up to speed about where decorators is at now :) The new spec looks very good and is poised to move into stage 3. At that point, we'll probably see transpiler and polyfill implementations. During that meeting we also talked about compatibility layers for transpiler migration. I think we'll probably wait for that to happen before we make any moves. Otherwise, it's a major breaking change to update our implementations. For vNext we can start from day 1 with the new spec.

[aicokleinovink]

So yesterday I wanted to upgrade to Babel 7 (because of Typescript support), but if I'm correct that won't work at the moment?? Because of the decorators getting transpiled differently?

[Jule-]

@aicokleinovink for what I have understood, you are right! It seems that there is possible implementation conflicts between aurelia and babel decorators.

[arabsight]

you can use the legacy option with the new plugin, and if you're using class-properties then the decorators plugin must come before class-properties pluginn and the later must must use loose mode:

const plugins = [
  ['@babel/plugin-proposal-decorators', { legacy: true }],
  ['@babel/plugin-proposal-class-properties', { loose: true }]
];