Allowing to re-save installation if LDS is enabled

Author: hermanliang

Parse/src/main/java/com/parse/OfflineStore.java

@@ -1456,7 +1456,17 @@ public Integer then(Task<List<T>> task) throws Exception {
       if (oldObjectId.equals(newObjectId)) {
         return;
       }
-      throw new RuntimeException("objectIds cannot be changed in offline mode.");
+      /**
+       * Special case for re-saving installation if it was deleted on the server
+       * @see ParseInstallation#saveAsync(String, Task)
+       */
+      if (object instanceof ParseInstallation
+          && newObjectId == null) {
+        classNameAndObjectIdToObjectMap.remove(Pair.create(object.getClassName(), oldObjectId));
+        return;
+      } else {
+        throw new RuntimeException("objectIds cannot be changed in offline mode.");
+      }
     }
 
     String className = object.getClassName();

Parse/src/main/java/com/parse/ParseInstallation.java

@@ -143,9 +143,7 @@ public Task<T> then(Task<Void> task) throws Exception {
       @Override
       public Task<Void> then(Task<Void> task) throws Exception {
         // Retry the fetch as a save operation because this Installation was deleted on the server.
-        // Do not attempt to resave an object if LDS is enabled, since changing objectId is not allowed.
-        if(!Parse.isLocalDatastoreEnabled()
-                && task.getError() != null
+        if(task.getError() != null
                 && task.getError() instanceof ParseException
                 && ((ParseException) task.getError()).getCode() == ParseException.OBJECT_NOT_FOUND) {
           synchronized (mutex) {

Parse/src/test/java/com/parse/ParseInstallationTest.java

@@ -108,6 +108,9 @@ public void testImmutableKeys() {
 
   @Test
   public void testSaveAsync() throws Exception {
+    OfflineStore lds = new OfflineStore(RuntimeEnvironment.application);
+    Parse.setLocalDatastore(lds);
+
     String sessionToken = "sessionToken";
     Task<Void> toAwait = Task.forResult(null);
 
@@ -119,11 +122,13 @@ public void testSaveAsync() throws Exception {
     ParseCorePlugins.getInstance()
         .registerCurrentInstallationController(controller);
     ParseObject.State state = new ParseObject.State.Builder("_Installation")
+        .objectId("oldId")
         .put("deviceToken", "deviceToken")
         .build();
     ParseInstallation installation = ParseInstallation.getCurrentInstallation();
     assertNotNull(installation);
     installation.setState(state);
+    installation.put("key", "value");
 
     ParseObjectController objController = mock(ParseObjectController.class);
     // mock return task when Installation was deleted on the server