fix inner stream with async iterables (#4544)

introduced in #4543

Author: yaacovCR

src/execution/Executor.ts

@@ -1053,10 +1053,10 @@ export class Executor {
     deliveryGroupMap: ReadonlyMap<DeferUsage, DeliveryGroup> | undefined,
   ): Promise<ReadonlyArray<unknown>> {
     // do not stream inner lists of multi-dimensional lists
-    const streamUsage = getStreamUsage(
-      this.validatedExecutionArgs,
-      fieldDetailsList,
-    );
+    const streamUsage =
+      typeof path.key === 'number'
+        ? undefined
+        : this.getStreamUsage(fieldDetailsList);
 
     let containsPromise = false;
     const completedResults: Array<unknown> = [];

src/execution/__tests__/stream-test.ts

@@ -695,12 +695,18 @@ describe('Execute: stream directive', () => {
     ]);
   });
   it('Can stream multi-dimensional lists from async iterable', async () => {
+    async function* innerList(fruit: string) {
+      for (let i = 0; i < 3; i++) {
+        // eslint-disable-next-line no-await-in-loop
+        yield await Promise.resolve(fruit);
+      }
+    }
     const document = parse('{ scalarListList @stream(initialCount: 1) }');
     const result = await complete(document, {
       async *scalarListList() {
-        yield await Promise.resolve(['apple', 'apple', 'apple']);
-        yield await Promise.resolve(['banana', 'banana', 'banana']);
-        yield await Promise.resolve(['coconut', 'coconut', 'coconut']);
+        yield await Promise.resolve(innerList('apple'));
+        yield await Promise.resolve(innerList('banana'));
+        yield await Promise.resolve(innerList('coconut'));
       },
     });
     expectJSON(result).toDeepEqual([