babel-plugin-transform-vue-tsx

Note

此插件基于babel-plugin-transform-vue-jsx修改，解决 TSX 语法严格类型下的一些问题:

对于 tsx, 标签的类型是限定的，为了支持其他类库的自定义组件正常使用，在vue-tsx-helper库中提供了 anyslot 标签，包含必须属性 is，其值为目标组件 id 例如在 TSX 中添加一个 vue-router link 使用<RouterLink></RouterLink>会报类型错误，但 TypeScript 认为固有标签应该全部是小写，因此也无法定义 RouterLink 的 type 使用<router-link></router-link>不适合 TSX 语法，因为不允许-字符

因此可以使用如下

import { Component, Prop } from "vue-property-decorator";
import { VueComponent } from "vue-tsx-helper"; // 同时全局提供了anyslot的类型定义
import TestComponent from "../TestComponent";

/**
 * Vue component props types
 */
interface IProps {}

@Component
export default class WrapTestComponent extends VueComponent<IProps> {
  @Prop() msg;

  render(h) {
    return (
      <TestComponent msg={"msg from parent"}>
        <h2>Page writed without .vue but plain tsx</h2>
        <anyslot is="router-link" to="/">
          Back to home
        </anyslot>
      </TestComponent>
    );
  }
}

Babel plugin for Vue 2.0 TSX

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.

• This is mutually exclusive with babel-plugin-transform-react-jsx.

Usage

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

In your .babelrc:

{
  "presets": ["env"],
  "plugins": ["transform-vue-tsx"]
}

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>;
  }
});

h auto-injection

Starting with version 3.4.0 we automatically inject const h = this.$createElement in any method and getter (not functions or arrow functions) declared in ES2015 syntax that has JSX so you can drop the (h) parameter.

Vue.component("jsx-example", {
  render() {
    // h will be injected
    return <div id="foo">bar</div>;
  },
  myMethod: function() {
    // h will not be injected
    return <div id="foo">bar</div>;
  },
  someOtherMethod: () => {
    // h will not be injected
    return <div id="foo">bar</div>;
  }
});

@Component
class App extends Vue {
  get computed() {
    // h will be injected
    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', {
    // Component props
    props: {
      msg: 'hi'
    },
    // normal HTML attributes
    attrs: {
      id: 'foo'
    },
    // DOM props
    domProps: {
      innerHTML: 'bar'
    },
    // Event handlers are nested under "on", though
    // modifiers such as in v-on:keyup.enter are not
    // supported. You'll have to manually check the
    // keyCode in the handler instead.
    on: {
      click: this.clickHandler
    },
    // For components only. Allows you to listen to
    // native events, rather than events emitted from
    // the component using vm.$emit.
    nativeOn: {
      click: this.nativeClickHandler
    },
    // 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',
    // assign the `ref` is used on elements/components with v-for
    refInFor: true,
    slot: 'slot'
  })
}

The equivalent of the above in Vue 2.0 JSX is:

render (h) {
  return (
    <div
      // normal attributes or component props.
      id="foo"
      // DOM properties are prefixed with `domProps`
      domPropsInnerHTML="bar"
      // event listeners are prefixed with `on` or `nativeOn`
      onClick={this.clickHandler}
      nativeOnClick={this.nativeClickHandler}
      // other special top-level properties
      class={{ foo: true, bar: false }}
      style={{ color: 'red', fontSize: '14px' }}
      key="key"
      ref="ref"
      // assign the `ref` is used on elements/components with v-for
      refInFor
      slot="slot">
    </div>
  )
}

Component Tip

If a custom element starts with lowercase, it will be treated as a string id and used to lookup a registered component. If it starts with uppercase, it will be treated as an identifier, which allows you to do:

import Todo from "./Todo.js";

export default {
  render(h) {
    return <Todo />; // no need to register Todo via components option
  }
};

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'] }

Vue directives

Note that almost all built-in Vue directives are not supported when using JSX, the sole exception being v-show, which can be used with the v-show={value} syntax. In most cases there are obvious programmatic equivalents, for example v-if is just a ternary expression, and v-for is just an array.map() expression, etc.

For custom directives, you can use the v-name={value} syntax. However, note that directive arguments and modifiers are not supported using this syntax. There are two workarounds:

1. Pass everything as an object via value, e.g. v-name={{ value, modifier: true }}

2. Use the raw vnode directive data format:

const directives = [{ name: "my-dir", value: 123, modifiers: { abc: true } }];

return <div {...{ directives }} />;