fix: throw on top-level await

Author: antfu

README.md

@@ -161,7 +161,7 @@ If you enjoy using `<script setup>`, you might also want to try [`vue-global-api
 - [x] Vite plugin
 - [x] Webpack plugin
 - [x] Nuxt module
-- [ ] Top-level await
+- [ ] ~~Top-level await~~ (not supported)
 
 ## How?
 

src/core/macros.ts

@@ -245,6 +245,11 @@ export function applyMacros(nodes: Statement[]) {
     }
   }
 
+  function throwIfAwait(node: Node) {
+    if (node.type === 'AwaitExpression')
+      error('top-level await is not supported in Vue 2', node)
+  }
+
   nodes = nodes
     .map((raw: Node) => {
       let node = raw
@@ -260,13 +265,17 @@ export function applyMacros(nodes: Statement[]) {
               decl.init = t.memberExpression(t.identifier('__ctx'), t.identifier('emit')) as any
             else if (processDefineProps(decl.init) || processWithDefaults(decl.init))
               decl.init = t.identifier('__props') as any
+            else
+              throwIfAwait(decl.init)
           }
         }
       }
 
       if (processDefineEmits(node) || processDefineProps(node) || processDefineExpose(node))
         return null
 
+      throwIfAwait(node)
+
       return raw
     })
     .filter(Boolean) as Statement[]

test/errors.test.ts

@@ -0,0 +1,59 @@
+import { transform as t } from '../src'
+
+describe('errors', () => {
+  it('langs', () => {
+    expect(() =>
+      t(`
+<script setup>
+const a = 1
+</script>
+
+<script lang="ts">
+export default {}
+</script>
+`))
+      .toThrowError('<script setup> language must be the same as <script>')
+  })
+
+  it('defineProps', () => {
+    expect(() =>
+      t(`
+<script setup>
+defineProps()
+const a = defineProps()
+</script>
+`))
+      .toThrowError('duplicate defineProps() call')
+  })
+
+  it('top-level await', () => {
+    expect(() =>
+      t(`
+<script setup>
+defineProps()
+await something()
+</script>
+`))
+      .toThrowError('top-level await is not supported in Vue 2')
+
+    expect(() =>
+      t(`
+<script setup>
+defineProps()
+const {data} = await something()
+</script>
+`))
+      .toThrowError('top-level await is not supported in Vue 2')
+
+    expect(() =>
+      t(`
+<script setup>
+defineProps()
+const a = async () => {
+  await something()
+}
+</script>
+`))
+      .not.toThrow()
+  })
+})