iOS: TypeError: null is not an object (evaluating 'snapshot.documentID') #855

Author: EddyVerbruggen

src/firebase.ios.ts

@@ -2216,7 +2216,9 @@ firebase.firestore.collection = (collectionPath: string): firestore.CollectionRe
 
 firebase.firestore.onDocumentSnapshot = (docRef: FIRDocumentReference, callback: (doc: DocumentSnapshot) => void): () => void => {
   const listener = docRef.addSnapshotListener((snapshot: FIRDocumentSnapshot, error: NSError) => {
-    callback(new DocumentSnapshot(snapshot.documentID, snapshot.exists, firebase.toJsObject(snapshot.data())));
+    if (!error && snapshot) {
+      callback(new DocumentSnapshot(snapshot.documentID, snapshot.exists, firebase.toJsObject(snapshot.data())));
+    }
   });
 
   // There's a bug resulting this function to be undefined..