Retry updater when in-call app close is cancelled

app/main.ts

@@ -871,6 +871,7 @@ async function createWindow() {
       );
     }
     if (!shouldClose) {
+      updater.onRestartCancelled();
       return;
     }
 

app/window_state.ts

@@ -7,6 +7,10 @@ export function markShouldQuit(): void {
   shouldQuitFlag = true;
 }
 
+export function markShouldNotQuit(): void {
+  shouldQuitFlag = false;
+}
+
 export function shouldQuit(): boolean {
   return shouldQuitFlag;
 }

ts/updater/common.ts

@@ -21,6 +21,7 @@ import { app, ipcMain } from 'electron';
 
 import * as durations from '../util/durations';
 import { getTempPath, getUpdateCachePath } from '../../app/attachments';
+import { markShouldNotQuit, markShouldQuit } from '../../app/window_state';
 import { DialogType } from '../types/Dialogs';
 import * as Errors from '../types/errors';
 import { isAlpha, isBeta, isStaging } from '../util/version';
@@ -117,6 +118,8 @@ export abstract class Updater {
 
   private markedCannotUpdate = false;
 
+  private restarting = false;
+
   private readonly canRunSilently: () => boolean;
 
   constructor({
@@ -148,6 +151,26 @@ export abstract class Updater {
     return this.checkForUpdatesMaybeInstall(true);
   }
 
+  // If the updater was about to restart the app but the user cancelled it, show dialog
+  // to let them retry the restart
+  public onRestartCancelled(): void {
+    if (!this.restarting) {
+      return;
+    }
+
+    this.logger.info(
+      'updater/onRestartCancelled: restart was cancelled. showing update dialog.'
+    );
+    this.restarting = false;
+    markShouldNotQuit();
+
+    const mainWindow = this.getMainWindow();
+    mainWindow?.webContents.send(
+      'show-update-dialog',
+      DialogType.DownloadedUpdate
+    );
+  }
+
   public async start(): Promise<void> {
     this.logger.info('updater/start: starting checks...');
 
@@ -173,7 +196,7 @@ export abstract class Updater {
   //
 
   protected setUpdateListener(
-    performUpdateCallback: () => Promise<void>
+    performUpdateCallback: () => Promise<void> | void
   ): void {
     ipcMain.removeHandler('start-update');
     ipcMain.handleOnce('start-update', performUpdateCallback);
@@ -209,6 +232,11 @@ export abstract class Updater {
     });
   }
 
+  protected markRestarting(): void {
+    this.restarting = true;
+    markShouldQuit();
+  }
+
   //
   // Private methods
   //

ts/updater/index.ts

@@ -64,6 +64,12 @@ export async function force(): Promise<void> {
   }
 }
 
+export function onRestartCancelled(): void {
+  if (updater) {
+    updater.onRestartCancelled();
+  }
+}
+
 function autoUpdateDisabled() {
   return (
     process.platform === 'linux' || process.mas || !config.get('updatesEnabled')

ts/updater/macos.ts

@@ -9,7 +9,6 @@ import { join } from 'path';
 import { Updater, createTempDir, deleteTempDir } from './common';
 import { explodePromise } from '../util/explodePromise';
 import * as Errors from '../types/errors';
-import { markShouldQuit } from '../../app/window_state';
 import { DialogType } from '../types/Dialogs';
 
 export class MacOSUpdater extends Updater {
@@ -41,7 +40,7 @@ export class MacOSUpdater extends Updater {
 
     this.setUpdateListener(async () => {
       logger.info('downloadAndInstall: restarting...');
-      markShouldQuit();
+      this.markRestarting();
       autoUpdater.quitAndInstall();
     });
   }

ts/updater/windows.ts

@@ -10,7 +10,6 @@ import { app } from 'electron';
 import pify from 'pify';
 
 import { Updater } from './common';
-import { markShouldQuit } from '../../app/window_state';
 
 const readdir = pify(readdirCallback);
 const unlink = pify(unlinkCallback);
@@ -61,9 +60,9 @@ export class WindowsUpdater extends Updater {
         throw error;
       }
 
-      logger.info('downloadAndInstall: restarting...');
-      markShouldQuit();
-      app.quit();
+      // If interrupted at this point, we only want to restart (not reattempt install)
+      this.setUpdateListener(this.restart);
+      this.restart();
     };
 
     if (isSilent) {
@@ -75,6 +74,12 @@ export class WindowsUpdater extends Updater {
     this.setUpdateListener(doInstall);
   }
 
+  protected restart(): void {
+    this.logger.info('downloadAndInstall: restarting...');
+    this.markRestarting();
+    app.quit();
+  }
+
   private async install(filePath: string, isSilent: boolean): Promise<void> {
     if (this.installing) {
       return;