Unit tests.

Author: DellaBitta

packages/firestore/src/api/snapshot.ts

@@ -523,8 +523,8 @@ export class DocumentSnapshot<
     if (this.metadata.hasPendingWrites) {
       throw new FirestoreError(
         Code.FAILED_PRECONDITION,
-        'DocumentSnapshot.toJSON attempted to serialize a document with pending writes. ' +
-          'Await `waitForPendingWrites()` before invoking `toJSON()`.'
+        'DocumentSnapshot.toJSON() attempted to serialize a document with pending writes. ' +
+          'Await waitForPendingWrites() before invoking toJSON().'
       );
     }
     builder.addBundleDocument(
@@ -713,8 +713,8 @@ export class QuerySnapshot<
       if (this.metadata.hasPendingWrites) {
         throw new FirestoreError(
           Code.FAILED_PRECONDITION,
-          'QuerySnapshot.toJSON attempted to serialize a document with pending writes. ' +
-            'Await `waitForPendingWrites()` before invoking `toJSON()`.'
+          'QuerySnapshot.toJSON() attempted to serialize a document with pending writes. ' +
+            'Await waitForPendingWrites() before invoking toJSON().'
         );
       }
       docBundleDataArray.push(

packages/firestore/test/unit/api/database.test.ts

@@ -19,6 +19,7 @@ import { expect } from 'chai';
 
 import {
   connectFirestoreEmulator,
+  loadBundle,
   refEqual,
   snapshotEqual,
   queryEqual
@@ -35,6 +36,15 @@ import {
 } from '../../util/api_helpers';
 import { keys } from '../../util/helpers';
 
+describe('Bundle', () => {
+  it('loadBundle silently exits with an empty bundle string)', async () => {
+    const db = newTestFirestore();
+    expect(async () => {
+      await loadBundle(db, '');
+    }).to.not.throw;
+  });
+});
+
 describe('CollectionReference', () => {
   it('support equality checking with isEqual()', () => {
     expect(refEqual(collectionReference('foo'), collectionReference('foo'))).to
@@ -107,6 +117,44 @@ describe('DocumentSnapshot', () => {
   it('JSON.stringify() does not throw', () => {
     JSON.stringify(documentSnapshot('foo/bar', { a: 1 }, true));
   });
+
+  it('toJSON returns a bundle', () => {
+    const json = documentSnapshot(
+      'foo/bar',
+      { a: 1 },
+      /*fromCache=*/ true
+    ).toJSON();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle).to.exist;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle.length).to.be.greaterThan(0);
+  });
+
+  it('toJSON returns an empty bundle when there are no documents', () => {
+    const json = documentSnapshot(
+      'foo/bar',
+      /*data=*/ null,
+      /*fromCache=*/ true
+    ).toJSON();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle).to.exist;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle.length).to.equal(0);
+  });
+
+  it('toJSON throws when there are pending writes', () => {
+    expect(() => {
+      documentSnapshot(
+        'foo/bar',
+        {},
+        /*fromCache=*/ true,
+        /*hasPendingWrites=*/ true
+      ).toJSON();
+    }).to.throw(
+      `DocumentSnapshot.toJSON() attempted to serialize a document with pending writes. ` +
+        `Await waitForPendingWrites() before invoking toJSON().`
+    );
+  });
 });
 
 describe('Query', () => {
@@ -229,6 +277,45 @@ describe('QuerySnapshot', () => {
       querySnapshot('foo', {}, { a: { a: 1 } }, keys(), false, false)
     );
   });
+
+  it('toJSON returns a bundle', () => {
+    const json = querySnapshot(
+      'foo',
+      {},
+      { a: { a: 1 } },
+      keys(),
+      false,
+      false
+    ).toJSON();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle).to.exist;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle.length).to.be.greaterThan(0);
+  });
+
+  it('toJSON returns a bundle when there are no documents', () => {
+    const json = querySnapshot('foo', {}, {}, keys(), false, false).toJSON();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle).to.exist;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    expect((json as any).bundle.length).to.be.greaterThan(0);
+  });
+
+  it('toJSON throws when there are pending writes', () => {
+    expect(() =>
+      querySnapshot(
+        'foo',
+        {},
+        { a: { a: 1 } },
+        keys('foo/a'),
+        true,
+        true
+      ).toJSON()
+    ).to.throw(
+      `QuerySnapshot.toJSON() attempted to serialize a document with pending writes. ` +
+        `Await waitForPendingWrites() before invoking toJSON().`
+    );
+  });
 });
 
 describe('SnapshotMetadata', () => {

packages/firestore/test/util/api_helpers.ts

@@ -79,8 +79,12 @@ export function documentReference(path: string): DocumentReference {
 export function documentSnapshot(
   path: string,
   data: JsonObject<unknown> | null,
-  fromCache: boolean
+  fromCache: boolean,
+  hasPendingWrites?: boolean
 ): DocumentSnapshot {
+  if (hasPendingWrites === undefined) {
+    hasPendingWrites = false;
+  }
   const db = firestore();
   const userDataWriter = new ExpUserDataWriter(db);
   if (data) {
@@ -89,7 +93,7 @@ export function documentSnapshot(
       userDataWriter,
       key(path),
       doc(path, 1, data),
-      new SnapshotMetadata(/* hasPendingWrites= */ false, fromCache),
+      new SnapshotMetadata(hasPendingWrites, fromCache),
       /* converter= */ null
     );
   } else {
@@ -98,7 +102,7 @@ export function documentSnapshot(
       userDataWriter,
       key(path),
       null,
-      new SnapshotMetadata(/* hasPendingWrites= */ false, fromCache),
+      new SnapshotMetadata(hasPendingWrites, fromCache),
       /* converter= */ null
     );
   }