feat(electron-updater): follow autoInstallOnAppQuit = false on macOS (

#5271)

Make electron-updater on macOS behave more like other OS's by only exposing the downloaded update file to Squirrel.Mac on applying it. This circumvents Squirrel.Mac limitation of not being able to NOT apply an update after it (squirrel) had downloaded it.

packages/electron-updater/src/AppUpdater.ts

@@ -26,8 +26,6 @@ export abstract class AppUpdater extends EventEmitter {
 
   /**
    * Whether to automatically install a downloaded update on app quit (if `quitAndInstall` was not called before).
-   *
-   * Applicable only on Windows and Linux.
    */
   autoInstallOnAppQuit: boolean = true
 

packages/electron-updater/src/MacUpdater.ts

@@ -5,14 +5,14 @@ import { createServer, IncomingMessage, ServerResponse } from "http"
 import { AddressInfo } from "net"
 import { AppAdapter } from "./AppAdapter"
 import { AppUpdater, DownloadUpdateOptions } from "./AppUpdater"
-import { ResolvedUpdateFileInfo, UpdateDownloadedEvent } from "./main"
+import { ResolvedUpdateFileInfo } from "./main"
 import { findFile } from "./providers/Provider"
 import AutoUpdater = Electron.AutoUpdater
 
 export class MacUpdater extends AppUpdater {
   private readonly nativeUpdater: AutoUpdater = require("electron").autoUpdater
 
-  private updateInfoForPendingUpdateDownloadedEvent: UpdateDownloadedEvent | null = null
+  private squirrelDownloadedUpdate: boolean = false
 
   constructor(options?: AllPublishOptions, app?: AppAdapter) {
     super(options, app)
@@ -22,15 +22,11 @@ export class MacUpdater extends AppUpdater {
       this.emit("error", it)
     })
     this.nativeUpdater.on("update-downloaded", () => {
-      const updateInfo = this.updateInfoForPendingUpdateDownloadedEvent
-      this.updateInfoForPendingUpdateDownloadedEvent = null
-      this.dispatchUpdateDownloaded(updateInfo!!)
+      this.squirrelDownloadedUpdate = true
     })
   }
 
   protected doDownloadUpdate(downloadUpdateOptions: DownloadUpdateOptions): Promise<Array<string>> {
-    this.updateInfoForPendingUpdateDownloadedEvent = null
-
     let files = downloadUpdateOptions.updateInfoAndProvider.provider.resolveFiles(downloadUpdateOptions.updateInfoAndProvider.info);
 
     // Allow arm64 macs to install universal or rosetta2(x64) - https://github.com/electron-userland/electron-builder/pull/5524
@@ -63,7 +59,6 @@ export class MacUpdater extends AppUpdater {
       },
       done: async event => {
         const downloadedFile = event.downloadedFile
-        this.updateInfoForPendingUpdateDownloadedEvent = event
         let updateFileSize = zipFileInfo.info.size
         if (updateFileSize == null) {
           updateFileSize = (await stat(downloadedFile)).size
@@ -130,14 +125,32 @@ export class MacUpdater extends AppUpdater {
             })
 
             this.nativeUpdater.once("error", reject)
-            this.nativeUpdater.checkForUpdates()
+
+            // The update has been dowloaded and is ready to be served to Squirrel
+            this.dispatchUpdateDownloaded(event)
+
+            if (this.autoInstallOnAppQuit) {
+              // This will trigger fetching and installing the file on Squirrel side
+              this.nativeUpdater.checkForUpdates()
+            }
           })
         })
       }
     })
   }
 
   quitAndInstall(): void {
-    this.nativeUpdater.quitAndInstall()
+    if (this.squirrelDownloadedUpdate) {
+      // Update already fetched by Squirrel, it's ready to install
+      this.nativeUpdater.quitAndInstall()
+    } else {
+      // Quit and install as soon as Squirrel get the update
+      this.nativeUpdater.on("update-downloaded", () => {
+        this.nativeUpdater.quitAndInstall()
+      })
+
+      // And trigger the update
+      this.nativeUpdater.checkForUpdates()
+    }
   }
 }