feat: transpile object rest spread with Object.assign by default

Author: yyx990803

README.md

@@ -2,6 +2,8 @@ This is an internal package used by `vue-loader` and `vueify`. It processes the
 
 1. add support to ES2015 features in template expressions via Buble. (see [supported features here](https://buble.surge.sh/guide/#supported-features)).
 
+**Note:** since version 1.8.0, object rest spread usage inside templates are transpiled to `Object.assign` calls by default. This means if you need to support IE, you will need to polyfill `Object.assign`. (Latest version of Vue CLI will do this for you).
+
 2. remove the `with` block inside render functions to make it strict-mode compliant. This is performed only at build time so that the base template compiler can be extremely small and lightweight.
 
 The buble implementation is built from a fork at https://github.com/yyx990803/buble

index.js

@@ -8,7 +8,9 @@ var defaultOptions = {
     stripWith: true,
     // custom feature ensures with context targets functional render
     stripWithFunctional: false
-  }
+  },
+  // allow spread...
+  objectAssign: 'Object.assign'
 }
 
 module.exports = function transpile (code, opts) {

test.js

@@ -9,6 +9,7 @@ test('should work', () => {
     <div>
       <div>{{ foo }} {{ process.env.BAR }}</div>
       <div v-for="{ name } in items">{{ name }}</div>
+      <div v-bind="{ ...a, ...b }"/>
     </div>
   `)
 
@@ -24,11 +25,17 @@ test('should work', () => {
       items: [
         { name: 'foo' },
         { name: 'bar' }
-      ]
+      ],
+      a: { id: 'foo' },
+      b: { class: 'bar' }
     },
     render: toFunction(res.render),
     staticRenderFns: res.staticRenderFns.map(toFunction)
   }).$mount()
 
-  expect(vm.$el.innerHTML).toMatch(`<div>hello bar</div> <div>foo</div><div>bar</div>`)
+  expect(vm.$el.innerHTML).toMatch(
+    `<div>hello bar</div> ` +
+    `<div>foo</div><div>bar</div> ` +
+    `<div id="foo" class="bar"></div>`
+  )
 })