[fix] support top-level await for module #104

src/evaluate/index.ts

@@ -8,7 +8,7 @@ import * as identifier from './identifier'
 import * as statement from './statement'
 import * as literal from './literal'
 import * as pattern from './pattern'
-/*<add>*//*import * as program from './program'*//*</add>*/
+import * as program from './program'
 
 let evaluateOps: any
 
@@ -25,7 +25,7 @@ export default function* evaluate(node: Node, scope: Scope) {
       statement,
       literal,
       pattern,
-      /*<add>*//*program*//*</add>*/
+      program
     )
   }
 

src/index.ts

@@ -4,7 +4,10 @@ import { EXPORTS, IMPORT } from './share/const'
 import { version } from '../package.json'
 import Scope from './scope'
 
+import { runAsync } from './share/async'
+import { hoist as hoistAsync } from './evaluate/helper'
 import { hoist } from './evaluate_n/helper'
+import evaluateAsync from './evaluate'
 import evaluate from './evaluate_n'
 
 export interface SvalOptions {
@@ -76,9 +79,21 @@ class Sval {
   }
 
   run(code: string | Node) {
-    const ast = typeof code === 'string' ? parse(code, this.options) as Node : code
-    hoist(ast as Program, this.scope)
-    evaluate(ast, this.scope)
+    const ast = typeof code === 'string' ? this.parse(code) : code
+    const scope = this.scope
+    // check if top-level await supports
+    if (this.options.sourceType === 'module' && (
+      this.options.ecmaVersion === 'latest'
+      || this.options.ecmaVersion >= 13
+    )) {
+      runAsync((function* () {
+        yield* hoistAsync(ast as Program, scope)
+        yield* evaluateAsync(ast, scope)
+      })())
+    } else {
+      hoist(ast as Program, scope)
+      evaluate(ast, scope)
+    }
   }
 }
 

tests/expression.test.ts

@@ -414,4 +414,19 @@ describe('testing src/expression.ts', () => {
       })
     `)
   })
+
+  it('should support top-level await', done => {
+    const interpreter = new Sval({ sourceType: 'module' })
+    interpreter.import('done', { default: done })
+    interpreter.import('expect', { default: expect })
+    interpreter.import('module', () => ({ default: 1 }))
+    interpreter.run(`
+      import done from 'done'
+      import expect from 'expect'
+      expect(await new Promise((resolve) => {
+        setTimeout(() => resolve(1), 50)
+      })).toBe(1)
+      done()
+    `)
+  })
 })