From 0c550f3586293af2ffcab46ad61fd8a6e9dbed7f Mon Sep 17 00:00:00 2001
From: Elton Gao <gyfelton@gmail.com>
Date: Thu, 9 Nov 2017 10:34:52 -0500
Subject: [PATCH] Make sure the promise is resolved/rejected for transaction

Right now the following code will be broken:
```
async function() {
  await ref.transaction(
              function(foo) {
                 // deal with foo
              },
              function(error, committed, ss) {
                 // additional work on complete callback
              },
              true
          );
  // NOTE: Code from here will never execute because promise above never gets resolved
}
```
v2 is not returning at the point of calling onComplete, v3 code does
---
 lib/modules/database/reference.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/modules/database/reference.js b/lib/modules/database/reference.js
index ffb1af9f..83f535ac 100644
--- a/lib/modules/database/reference.js
+++ b/lib/modules/database/reference.js
@@ -195,8 +195,11 @@ export default class Reference extends ReferenceBase {
     return new Promise((resolve, reject) => {
       const onCompleteWrapper = (error, committed, snapshotData) => {
         if (isFunction(onComplete)) {
-          if (error) return onComplete(error, committed, null);
-          return onComplete(null, committed, new Snapshot(this, snapshotData));
+          if (error)  { 
+            onComplete(error, committed, null); 
+          } else {
+            onComplete(null, committed, new Snapshot(this, snapshotData));
+          }
         }
 
         if (error) return reject(error);