Unmount before install

src/redux/actions/install_actions.js

@@ -13,6 +13,7 @@ import {
   setReleaseUpgradeAvailable
 } from './release_version_actions';
 import {
+  confirmYesNo,
   displaySelectAppPlatform,
   setAllowMount,
   setApplicationReady,
@@ -21,6 +22,7 @@ import {
   showWindow,
   shutdownApplication
 } from './common_actions';
+import {unmountAll} from './mount_actions';
 
 const ipcRenderer = getIPCRenderer();
 
@@ -188,18 +190,25 @@ export const installAndTestRelease = (source, version, appPlatform) => {
 
 export const installReleaseByVersion = (release, version) => {
   return (dispatch, getState) => {
-    let allowInstall = !getState().mounts.MountsBusy;
+    const install = () => {
-    if (!allowInstall) {
-      // TODO: prompt to unmount
-    }
-
-    if (allowInstall) {
       if (getState().download.AllowDownload && !getState().download.DownloadActive) {
         dispatch(setAutoInstallRelease(true));
         dispatch(setActiveRelease(release, version));
       } else {
         notifyError('Download is active. Unable to install release.');
       }
+    };
+
+    if (getState().mounts.MountsBusy) {
+      dispatch(confirmYesNo('Unmount all drives?'))
+        .then(confirmed => {
+          if (confirmed) {
+            dispatch(unmountAll(install));
+          }
+        })
+        .catch(error => notifyError(error));
+    } else {
+      install();
     }
   };
 };