move squirrel bahaviour into proper place

atom/browser/api/lib/auto-updater/auto-updater-win.coffee

@@ -1,10 +1,12 @@
 {EventEmitter} = require 'events'
 SquirrelUpdate = require './auto-updater/squirrel-update-win'
+app            = require('app')
 
 class AutoUpdater extends EventEmitter
 
   quitAndInstall: ->
-    # TODO
+    SquirrelUpdate.processStart ->
+      app.quit()
 
   setFeedUrl: (updateUrl) ->
     # set feed URL only when it hasn't been set before
@@ -36,27 +38,16 @@ class AutoUpdater extends EventEmitter
           @emit 'update-not-available'
           return
 
+        # info about the newly installed version and a function any of the event listeners can call to restart the application
         @emit 'update-downloaded', {}, update.releaseNotes, update.version, new Date(), @updateUrl, => @quitAndInstall()
 
   downloadUpdate: (callback) ->
-    SquirrelUpdate.spawn ['--download', @updateUrl], (error, stdout) ->
-      return callback(error) if error?
-
-      try
-        # Last line of output is the JSON details about the releases
-        json   = stdout.trim().split('\n').pop()
-        update = JSON.parse(json)?.releasesToApply?.pop?()
-      catch error
-        error.stdout = stdout
-        return callback(error)
-
-      callback(null, update)
+    SquirrelUpdate.download(callback)
 
   installUpdate: (callback) ->
-    SquirrelUpdate.spawn(['--update', @updateUrl], callback)
+    SquirrelUpdate.update(@updateUrl, callback)
 
   supportsUpdates: ->
-    SquirrelUpdate.existsSync()
-
+    SquirrelUpdate.supported()
 
 module.exports = new AutoUpdater()

atom/browser/api/lib/auto-updater/squirrel-update-win.coffee

@@ -9,11 +9,11 @@ exeName               = path.basename(process.execPath)
 
 # Spawn a command and invoke the callback when it completes with an error
 # and the output from standard out.
-spawn = (command, args, callback) ->
+spawnUpdate = (args, callback) ->
   stdout = ''
 
   try
-    spawnedProcess = ChildProcess.spawn(command, args)
+    spawnedProcess = ChildProcess.spawn(updateDotExe, args)
   catch error
     # Spawn can throw an error
     process.nextTick -> callback?(error, stdout)
@@ -29,14 +29,29 @@ spawn = (command, args, callback) ->
     error?.stdout ?= stdout
     callback?(error, stdout)
 
-# Spawn the Update.exe with the given arguments and invoke the callback when
-# the command completes.
-spawnUpdate = (args, callback) ->
-  spawn(updateDotExe, args, callback)
+processStart = (callback) ->
+  spawnUpdate(['--processStart', exeName], callback)
 
-# Exports
-exports.spawn = spawnUpdate
+download = (callback) ->
+  spawnUpdate ['--download', @updateUrl], (error, stdout) ->
+    return callback(error) if error?
 
-# Is the Update.exe installed with Atom?
-exports.existsSync = ->
+    try
+      # Last line of output is the JSON details about the releases
+      json   = stdout.trim().split('\n').pop()
+      update = JSON.parse(json)?.releasesToApply?.pop?()
+    catch error
+      error.stdout = stdout
+      return callback(error)
+
+    callback(null, update)
+
+update = (updateUrl, callback) ->
+  spawnUpdate ['--update', updateUrl], callback
+
+# Is the Update.exe installed with the current application?
+exports.supported = ->
   fs.accessSync(updateDotExe, fs.R_OK)
+exports.processStart = processStart
+exports.download     = download
+exports.update       = update