Updating array of Dates no longer converts it to array of strings (#770)

* Added explicit Date __Type field to Dates in Arrays

* Update CHANGELOG.md

* Reformatted to avoid nested ternary operators

Author: rihadavid

CHANGELOG.md

@@ -3,6 +3,7 @@
 ### NEXT RELEASE
 
 * _Contributing to this repo? Add info about your change here to be included in next release_
+* Fix: Updating array of Dates now keeps it's type (was changing to array of ISO strings, issue #590), thanks to [David Riha](https://github.com/rihadavid)
 * Fix: NaN displayed when filter input is empty or negative number (#749), thanks to [Miguel Serrrano](https://github.com/miguel-s)
 * Fix: Addresses issue related to displaying iOS alert object containing title and body keys (#539), thanks to [Robert Martin del Campo](https://github.com/repertus)
 

src/dashboard/Data/Browser/BrowserTable.react.js

@@ -201,7 +201,15 @@ export default class BrowserTable extends React.Component {
             value = '';
           } else if (type === 'Array') {
             if (value) {
-              value = value.map(val => val instanceof Parse.Object ? val.toPointer() : val);
+              value = value.map(val => {
+                  if (val instanceof Parse.Object) {
+                      return val.toPointer();
+                  } else if (typeof val.getMonth === 'function') {
+                      return { __type: "Date", iso: val.toISOString() };
+                  }
+
+                  return val;
+              });
             }
           }
           let wrapTop = Math.max(0, this.props.current.row * ROW_HEIGHT);