feat: use native recursiveDelete for collection cleanup (#408)

* feat: use native recursiveDelete for collection cleanup

* chore: revert package.json to original state as requested

Author: angelcaamal

firestore/main/index.js

@@ -947,37 +947,9 @@ async function multipleCursorConditions(db) {
 }
 
 // [START firestore_data_delete_collection]
-async function deleteCollection(db, collectionPath, batchSize) {
+async function deleteCollection(db, collectionPath) {
   const collectionRef = db.collection(collectionPath);
-  const query = collectionRef.orderBy('__name__').limit(batchSize);
-
-  return new Promise((resolve, reject) => {
-    deleteQueryBatch(db, query, resolve).catch(reject);
-  });
-}
-
-async function deleteQueryBatch(db, query, resolve) {
-  const snapshot = await query.get();
-
-  const batchSize = snapshot.size;
-  if (batchSize === 0) {
-    // When there are no documents left, we are done
-    resolve();
-    return;
-  }
-
-  // Delete documents in a batch
-  const batch = db.batch();
-  snapshot.docs.forEach((doc) => {
-    batch.delete(doc.ref);
-  });
-  await batch.commit();
-
-  // Recurse on the next process tick, to avoid
-  // exploding the stack.
-  process.nextTick(() => {
-    deleteQueryBatch(db, query, resolve);
-  });
+  return await db.recursiveDelete(collectionRef);
 }
 
 // [END firestore_data_delete_collection]
@@ -1019,7 +991,7 @@ describe('Firestore Smoketests', () => {
   });
 
   it('should delete existing documents', () => {
-    return deleteCollection(db, 'cities', 50);
+    return deleteCollection(db, 'cities');
   });
 
   it('should store example data', () => {
@@ -1081,7 +1053,7 @@ describe('Firestore Smoketests', () => {
   it('should handle transaction with a result', () => {
     return transactionWithResult(db).then(res => {
       // Delete data set
-      return deleteCollection(db, 'cities', 50);
+      return deleteCollection(db, 'cities');
     });
   });
 
@@ -1178,7 +1150,7 @@ describe('Firestore Smoketests', () => {
   });
 
   it('should delete the whole collection', () => {
-    return deleteCollection(db, 'cities', 50);
+    return deleteCollection(db, 'cities');
   });
 
   it('should find all museums when querying a collection group', () => {