Add integration test.

Author: DellaBitta

packages/firestore/test/integration/api/query.test.ts

@@ -37,9 +37,11 @@ import {
   endAt,
   endBefore,
   GeoPoint,
+  getDocFromCache,
   getDocs,
   limit,
   limitToLast,
+  loadBundle,
   onSnapshot,
   or,
   orderBy,
@@ -74,6 +76,44 @@ import { captureExistenceFilterMismatches } from '../util/testing_hooks_util';
 apiDescribe('Queries', persistence => {
   addEqualityMatcher();
 
+  it('QuerySnapshot.toJSON bundle getDocFromCache', async () => {
+    let path: string | null = null;
+    let jsonBundle: object | null = null;
+    const testDocs = {
+      a: { k: 'a' },
+      b: { k: 'b' },
+      c: { k: 'c' }
+    };
+    // Write an initial document in an isolated Firestore instance so it's not stored in the cache.
+    await withTestCollection(persistence, testDocs, async collection => {
+      await getDocs(query(collection)).then(querySnapshot => {
+        expect(querySnapshot.docs.length).to.equal(3);
+        // Find the path to a known doc.
+        querySnapshot.docs.forEach(docSnapshot => {
+          if (docSnapshot.ref.path.endsWith('a')) {
+            path = docSnapshot.ref.path;
+          }
+        });
+        expect(path).to.not.be.null;
+        jsonBundle = querySnapshot.toJSON();
+      });
+    });
+    expect(jsonBundle).to.not.be.null;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    const json = (jsonBundle as any).bundle;
+    expect(json).to.exist;
+    expect(json.length).to.be.greaterThan(0);
+    // Use a new instance to load the bundle to ensure that the cache is primed by the bundle and
+    // not the previous getDocs call.
+    await withTestDb(persistence, async db => {
+      await loadBundle(db, json);
+      const docRef = doc(db, path!);
+      const docSnap = await getDocFromCache(docRef);
+      expect(docSnap.exists);
+      expect(docSnap.data()).to.deep.equal(testDocs.a);
+    });
+  });
+
   it('can issue limit queries', () => {
     const testDocs = {
       a: { k: 'a' },