babel-plugin-transform-vue-jsx

Babel plugin for Vue 2.0 JSX

Requirements

• Assumes you are using Babel with a module bundler e.g. Webpack, because the spread merge helper is imported as a module to avoid duplication.

Usage

npm install
  babel-plugin-syntax-jsx\
  babel-plugin-transform-vue-jsx\
  babel-helper-vue-jsx-merge-props\
  --save-dev

In your .babelrc:

{
  "presets": ["es2015"],
  "plugins": ["transform-vue-jsx"]
}

The plugin transpiles the following JSX:

<div id="foo">{this.text}</div>

To the following JavaScript:

h('div', {
  attrs: {
    id: 'foo'
  }
}, [this.text])

Note the h function, which is a shorthand for a Vue instance's $createElement method, must be in the scope where the JSX is. Since this method is passed to component render functions as the first argument, in most cases you'd do this:

Vue.component('jsx-example', {
  render (h) { // <-- h must be in scope
    return <div id="foo">bar</div>
  }
})

Difference from React JSX

First, Vue 2.0's vnode format is different from React's. The second argument to the createElement call is a "data object" that accepts nested objects. Each nested object will be then processed by corresponding modules:

render (h) {
  return h('div', {
    // normal HTML attributes
    attrs: {
      id: 'foo'
    },
    // DOM properties
    props: {
      innerHTML: 'bar'
    },
    // event handlers are nested under "on"
    on: {
      click: this.onClick
    },
    // class is a special module, same API as `v-bind:class`
    class: {
      foo: true,
      bar: false
    },
    // style is also same as `v-bind:style`
    style: {
      color: 'red',
      fontSize: '14px'
    },
    // other special top-level properties
    key: 'key',
    ref: 'ref',
    transition: 'fade'
  })
}

The equivalent of the above in Vue 2.0 JSX is:

render (h) {
  return (
    <div
      // normal attributes
      id="foo"
      // DOM properties are prefixed with prop-
      prop-innerHTML="bar"
      // event listeners are prefixed with on-
      on-click={this.onClick}
      // other special top-level properties
      class={{ foo: true, bar: false }}
      style={{ color: 'red', fontSize: '14px' }}
      key="key"
      ref="ref"
      transition="fade">
    </div>
  )
}

JSX Spread

JSX spread is supported, and this plugin will intelligently merge nested data properties. For example:

const data = {
  class: ['b', 'c']
}
const vnode = <div class="a" {...data}/>

The merged data will be:

{ class: ['a', 'b', 'c'] }