flow fixes that change logic slightly

lib/modules/database/transaction.js

@@ -50,7 +50,7 @@ export default class TransactionHandler extends Base {
       started: true,
     };
 
-    FirebaseDatabase.startTransaction(reference.path, id, applyLocally || false);
+    FirebaseDatabase.startTransaction(reference.path, id, applyLocally);
   }
 
   /**
@@ -77,7 +77,7 @@ export default class TransactionHandler extends Base {
       case 'update':
         return this._handleUpdate(event);
       case 'error':
-        return this._handleError(error);
+        return this._handleError(event);
       case 'complete':
         return this._handleComplete(event);
       default:

lib/utils/index.js

@@ -111,9 +111,9 @@ export function isFunction(item?: any): boolean {
  * @param string
  * @returns {*}
  */
-export function tryJSONParse(string) {
+export function tryJSONParse(string: string | null): any {
   try {
-    return JSON.parse(string);
+    return string && JSON.parse(string);
   } catch (jsonError) {
     return string;
   }
@@ -217,18 +217,25 @@ function _delayChunk(
  * @param iterator
  * @param cb
  */
-export function each(array: Array, chunkSize?: number, iterator: Function, cb: Function): void {
+export function each(
+  array: Array<*>,
+  chunkSize: number | Function,
+  iterator: Function,
+  cb?: Function
+): void {
   if (typeof chunkSize === 'function') {
     cb = iterator;
     iterator = chunkSize;
     chunkSize = DEFAULT_CHUNK_SIZE;
   }
 
-  _delayChunk(array, chunkSize, (slice, start) => {
-    for (let ii = 0, jj = slice.length; ii < jj; ii += 1) {
-      iterator(slice[ii], start + ii);
-    }
-  }, cb);
+  if (cb) {
+    _delayChunk(array, chunkSize, (slice, start) => {
+      for (let ii = 0, jj = slice.length; ii < jj; ii += 1) {
+        iterator(slice[ii], start + ii);
+      }
+    }, cb);
+  }
 }
 
 export function typeOf(value: any): string {
@@ -245,7 +252,12 @@ export function typeOf(value: any): string {
  * @param cb
  * @returns {*}
  */
-export function map(array: Array, chunkSize?: number, iterator: Function, cb: Function): void {
+export function map(
+  array: Array<*>,
+  chunkSize: number | Function,
+  iterator: Function,
+  cb?: Function
+): void {
   if (typeof chunkSize === 'function') {
     cb = iterator;
     iterator = chunkSize;
@@ -258,7 +270,7 @@ export function map(array: Array, chunkSize?: number, iterator: Function, cb: Fu
       result.push(iterator(slice[ii], start + ii, array));
     }
     return result;
-  }, () => cb(result));
+  }, () => cb && cb(result));
 }