Fix unintended early return in await inclusion handling.

src/ast/nodes/AwaitExpression.ts

@@ -15,10 +15,11 @@ export default class AwaitExpression extends NodeBase {
 	}
 
 	include(includeChildrenRecursively: IncludeChildren) {
-		if (!this.included && !this.context.usesTopLevelAwait) {
+		checkTopLevelAwait: if (!this.included && !this.context.usesTopLevelAwait) {
 			let parent = this.parent;
 			do {
-				if (parent instanceof FunctionNode || parent instanceof ArrowFunctionExpression) return;
+				if (parent instanceof FunctionNode || parent instanceof ArrowFunctionExpression)
+					break checkTopLevelAwait;
 			} while ((parent = (parent as Node).parent as Node));
 			this.context.usesTopLevelAwait = true;
 		}

test/function/samples/handles-async-await/_config.js

@@ -0,0 +1,8 @@
+const assert = require('assert');
+
+module.exports = {
+	description: 'properly handles exporting async functions',
+	exports(exports) {
+		return exports.callback().then(response => assert.strictEqual(response, 42));
+	}
+};

test/function/samples/handles-async-await/main.js

@@ -0,0 +1,4 @@
+export async function callback() {
+	const response = await Promise.resolve(43);
+	return response - 1;
+}