Adjust documentation for using @vue/babel-preset-app in a non vue-cli environment

[ChristianStornowski]

What problem does this feature solve?

Using ts-jest, babel, @vue/babel-preset-app and @babel/preset-typescript" together, causes tests failures even when setting typescript compiler option "module" to "commonjs" and "allowSyntheticDefaultImports" to "true".

.babelrc

{
  "presets": [
    "@vue/app",
    "@babel/preset-typescript"
  ]
}

What does the proposed API look like?

Documentation of setting environment variables before running ts-jest.

VUE_CLI_BABEL_TARGET_NODE = true
VUE_CLI_BABEL_TRANSPILE_MODULES = true
VUE_CLI_BUILD_TARGET = app

[LinusBorg]

I'm not sure that I can reproduce a project with the behaviouir you are seeing

• which options did you choose when installing?
• What changes, if any, did you make to the clean project?
• What command did you run?
• What error did you recieve?

[ChristianStornowski]

I created this online project: https://codesandbox.io/s/7w5qrwpxnq

npm test will failure with

import "core-js/modules/es6.promise";
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

SyntaxError: Unexpected string

npm run test:working is going to be fine. (maybe you have to delete jest tmp folder first (Linux: /tmp/jest_rs/).

[LinusBorg]

Oh, now i get it. Should have read your title more carefully.

So you are using the babel preset in an app not created with vue-cli, and had to dig into the yource to learn that you have to set some ENV variables to make it work the way you expect it to.

And your request would be that these env variables are documented in that preset's README.

Seems sensilbe. :)

[yyx990803]

@vue/babel-preset-app is specifically designed to use with projects created via Vue CLI. It does not consider uses cases outside of Vue CLI. We can make this more explicit in its README.

[victor71]

@vue/babel-preset-app is specifically designed to use with projects created via Vue CLI. It does not consider uses cases outside of Vue CLI. We can make this more explicit in its README.

How to determine core-js3 in @vue/babel-preset-app? I add the 'corejs' option to preset '@vue/app', but it now work.

[haoqunjiang]

@victor71, For now, use @vue/babel-preset-app v4.0.0-alpha.0. It's too much work for us to keep compatibility with both core-js versions, so we only bump the version in a new major release.

[victor71]

@sodatea Thank you!