fix: should work with variable named render (close #23)

Author: yyx990803

lib/compileTemplate.ts

@@ -149,11 +149,16 @@ function actuallyCompile (
     // transpile code with vue-template-es2015-compiler, which is a forked
     // version of Buble that applies ES2015 transforms + stripping `with` usage
     let code = transpile(
-      `var render = ${toFunction(render)}\n` +
-      `var staticRenderFns = [${staticRenderFns.map(toFunction)}]`,
+      `var __render__ = ${toFunction(render)}\n` +
+      `var __staticRenderFns__ = [${staticRenderFns.map(toFunction)}]`,
       finalTranspileOptions
     ) + `\n`
 
+    // #23 we use __render__ to avoid `render` not being prefixed by the
+    // transpiler when stripping with, but revert it back to `render` to
+    // maintain backwards compat
+    code = code.replace(/\s__(render|staticRenderFns)__\s/g, ' $1 ')
+
     if (!isProduction) {
       // mark with stripped (this enables Vue to use correct runtime proxy
       // detection)

test/compileTemplate.spec.ts

@@ -2,6 +2,26 @@ import { parse } from '../lib/parse'
 import { compileTemplate } from '../lib/compileTemplate'
 import * as compiler from 'vue-template-compiler'
 
+test('should work', () => {
+  const source = `<div><p>{{ render }}</p></div>`
+
+  const result = compileTemplate({
+    filename: 'example.vue',
+    source,
+    compiler: compiler
+  })
+
+  expect(result.errors.length).toBe(0)
+  expect(result.source).toBe(source)
+  // should expose render fns
+  expect(result.code).toMatch(`var render = function`)
+  expect(result.code).toMatch(`var staticRenderFns = []`)
+  // should mark with stripped
+  expect(result.code).toMatch(`render._withStripped = true`)
+  // should prefix bindings
+  expect(result.code).toMatch(`_vm.render`)
+})
+
 test('preprocess pug', () => {
   const template = parse({
     source: