Merge pull request soumak77#96 from Storr-co/run-transaction-return-value

Update Firestore.runTransaction to resolve promise with returned value

Author: soumak77

src/firestore.js

@@ -72,8 +72,13 @@ MockFirestore.prototype.runTransaction = function(transFunc) {
     return doc.get();
   };
   return new Promise(function(resolve, reject) {
-    transFunc(batch).then(function() {
-      batch.commit().then(resolve).catch(reject);
+    Promise.resolve(transFunc(batch)).then(function(value) {
+      batch
+        .commit()
+        .then(function () {
+          resolve(value);
+        })
+        .catch(reject);
     }).catch(reject);
   });
 };

test/unit/firestore.js

@@ -134,6 +134,18 @@ describe('MockFirestore', function () {
         }).catch(done);
       }).catch(done);
     });
+
+    it('returns the return value of the passed function', function () {
+      db.autoFlush();
+
+      return db.runTransaction(function(transaction) {
+        return transaction.get(db.doc('doc')).then(function() {
+          return 'cba';
+        });
+      }).then(function(transactionReturn) {
+        expect(transactionReturn).to.equal('cba');
+      });
+    });
   });
 
   describe('#batch', function () {