Adding queryWithMicrosecondPrecision test

Author: schmidt-sebastian

google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/it/ITSystemTest.java

@@ -201,7 +201,7 @@ public void serverTimestamp() throws Exception {
   }
 
   @Test
-  public void updateMicrosecondTimestamp() throws Exception {
+  public void timestampDoesntGetTruncatedDuringUpdate() throws Exception {
     DocumentReference documentReference = addDocument("time", Timestamp.ofTimeSecondsAndNanos(0, 123000));
     DocumentSnapshot documentSnapshot = documentReference.get().get();
 
@@ -265,6 +265,23 @@ public void noResults() throws Exception {
     assertNotNull(querySnapshot.getReadTime());
   }
 
+  @Test
+  public void queryWithMicrosecondPrecision() throws Exception {
+    Timestamp microsecondTimestamp = Timestamp.ofTimeSecondsAndNanos(0, 123000);
+
+    DocumentReference documentReference = addDocument("time",  microsecondTimestamp);
+    DocumentSnapshot documentSnapshot = documentReference.get().get();
+
+    Query query = randomColl.whereEqualTo("time", microsecondTimestamp);
+    QuerySnapshot querySnapshot = query.get().get();
+    assertEquals(1, querySnapshot.size());
+
+    // Using `.toDate()` truncates to millseconds, and hence the query doesn't match.
+    query = randomColl.whereEqualTo("time", microsecondTimestamp.toDate());
+    querySnapshot = query.get().get();
+    assertEquals(0, querySnapshot.size());
+  }
+
   @Test
   public void nestedQuery() throws Exception {
     randomColl = randomColl.document("foo").collection("bar");