Pushing wipes "future" history (codesandbox#1206)

* Pushing wipes "future" history

* Sanity check

Author: pshrmn

packages/app/src/app/components/Preview/index.js

@@ -590,7 +590,7 @@ class BasePreview extends React.Component<Props, State> {
         break;
       default:
         this.setState({
-          history: [...history, url],
+          history: [...history.slice(0, historyPosition + 1), url],
           historyPosition: historyPosition + 1,
           urlInAddressBar: url,
         });

packages/sandbox-hooks/url-listeners.js

@@ -17,9 +17,10 @@ let historyPosition = -1;
 let disableNextHashChange = false;
 
 function pushHistory(url, state) {
-  historyPosition += 1;
-  historyList.length = historyPosition + 1;
-  historyList[historyPosition] = { url, state };
+  // remove "future" locations
+  historyList.splice(historyPosition + 1);
+  historyList.push({ url, state });
+  historyPosition = historyList.length - 1;
 }
 
 function pathWithHash(location) {