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diff --git a/node_modules/@vue/babel-preset-app/README.md b/node_modules/@vue/babel-preset-app/README.md new file mode 100644 index 00000000..f00efa47 --- /dev/null +++ b/node_modules/@vue/babel-preset-app/README.md @@ -0,0 +1,81 @@ +# @vue/babel-preset-app + +This is the default Babel preset used in all Vue CLI projects. + +## Included + +- [babel-preset-env](https://github.com/babel/babel/tree/master/packages/babel-preset-env) + - `modules: false` + - auto set to `'commonjs'` in Jest tests + - [`useBuiltIns: 'usage'`](#usebuiltins) + - `targets` is determined: + - using `browserslist` field in `package.json` when building for browsers + - set to `{ node: 'current' }` when running unit tests in Node.js +- Includes `Promise` polyfill by default so that they are usable even in non-transpiled dependencies (only for environments that need it) +- [@babel/plugin-transform-runtime](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-runtime) + - Only enabled for helpers since polyfills are handled by `babel-preset-env` +- [dynamic import syntax](https://github.com/tc39/proposal-dynamic-import) +- [Object rest spread](https://github.com/tc39/proposal-object-rest-spread) +- [babel-preset-stage-2](https://github.com/babel/babel/tree/master/packages/babel-preset-stage-2) +- Vue JSX support + - [@babel/plugin-syntax-jsx](https://github.com/babel/babel/tree/master/packages/babel-plugin-syntax-jsx) + - [babel-plugin-transform-vue-jsx](https://github.com/vuejs/babel-plugin-transform-vue-jsx) + - ~~[babel-plugin-jsx-event-modifiers](https://github.com/nickmessing/babel-plugin-jsx-event-modifiers)~~ (temporarily disabled until fixed for Babel 7) + - ~~[babel-plugin-jsx-v-model](https://github.com/nickmessing/babel-plugin-jsx-v-model)~~ (temporarily disabled until fixed for Babel 7) + +## Options + +### modules + +- Default: + - `false` when building with webpack + - `'commonjs'` when running tests in Jest. + +Explicitly set `modules` option for `babel-preset-env`. See [babel-preset-env docs](https://github.com/babel/babel/tree/master/packages/babel-preset-env#modules) for more details. + +### targets + +- Default: + - determined from `browserslist` field in `package.json` when building for browsers + - set to `{ node: 'current' }` when running unit tests in Node.js + +Explicitly set `targets` option for `babel-preset-env`. See [babel-preset-env docs](https://github.com/babel/babel/tree/master/packages/babel-preset-env#targets) for more details. + +### useBuiltIns + +- Default: `'usage'` +- Allowed values: `'usage' | 'entry' | false` + +Explicitly set `useBuiltIns` option for `babel-preset-env`. + +The default value is `'usage'`, which adds imports to polyfills based on the usage in transpiled code. For example, if you use `Object.assign` in your code, the corresponding polyfill will be auto-imported if your target environment does not supports it. + +Note that the usage detection does not apply to your dependencies (which are excluded by `cli-plugin-babel` by default). If one of your dependencies need polyfills, you have a few options: + +1. **If the dependency is written in an ES version that your target environments do not support:** Add that dependency to the `transpileDependencies` option in `vue.config.js`. This would enable both syntax transforms and usage-based polyfill detection for that dependency. + +2. **If the dependency ships ES5 code and explicitly lists the polyfills needed:** you can pre-include the needed polyfills using the [polyfills](#polyfills) option for this preset. + +3. **If the dependency ships ES5 code, but uses ES6+ features without explicitly listing polyfill requirements (e.g. Vuetify):** Use `useBuiltIns: 'entry'` and then add `import '@babel/polyfill'` to your entry file. This will import **ALL** polyfills based on your `browserslist` targets so that you don't need to worry about dependency polyfills anymore, but will likely increase your final bundle size with some unused polyfills. + +See [babel-preset-env docs](https://github.com/babel/babel/tree/master/packages/babel-preset-env#usebuiltins) for more details. + +### polyfills + +- Default: `['es6.promise']` + +A list of [core-js](https://github.com/zloirock/core-js) polyfills to pre-include when using `useBuiltIns: 'usage'`. **These polyfills are automatically excluded if they are not needed for your target environments**. + +Use this option when you have 3rd party dependencies that are not processed by Babel but have specific polyfill requirements (e.g. Axios and Vuex require Promise support). + +### jsx + +- Default: `true`. + +Set to `false` to disable JSX support. + +### loose + +- Default: `false`. + +Setting this to `true` will generate code that is more performant but less spec-compliant. |