Save config changes on update

spec/app/editor-spec.coffee

@@ -502,7 +502,7 @@ describe "Editor", ->
       editor.getBuffer().saveAs("/tmp/atom-new.txt")
       expect(eventHandler).toHaveBeenCalled()
 
-  fdescribe "font size", ->
+  describe "font size", ->
     it "sets the initial font size based on the value from config", ->
       config.editor.fontSize = 20
       config.update()

spec/spec-helper.coffee

@@ -20,9 +20,10 @@ beforeEach ->
   window.fixturesProject = new Project(require.resolve('fixtures'))
   window.resetTimeouts()
 
-  # don't load user configuration
+  # don't load or save user configuration
   spyOn(config, 'load')
-  config.loadDefaults()
+  spyOn(config, 'save')
+  config.assignDefaults()
 
   # make editor display updates synchronous
   spyOn(Editor.prototype, 'requestDisplayUpdate').andCallFake -> @updateDisplay()

src/app/config.coffee

@@ -4,10 +4,9 @@ EventEmitter = require 'event-emitter'
 
 module.exports =
 class Config
-  constructor: ->
-    @configDirPath = fs.absolute("~/.atom")
-    @configJsonPath = fs.join(@configDirPath, "config.json")
-    @userInitScriptPath = fs.join(@configDirPath, "atom.coffee")
+  configDirPath: fs.absolute("~/.atom")
+  configJsonPath: fs.absolute("~/.atom/config.json")
+  userInitScriptPath: fs.absolute("~/.atom/atom.coffe")
 
   load: ->
     if fs.exists(@configJsonPath)
@@ -23,8 +22,18 @@ class Config
     _.defaults(@editor, require('editor').configDefaults)
 
   update: ->
+    @save()
     @trigger 'update'
 
+  save: ->
+    keysToWrite = _.clone(this)
+    delete keysToWrite.eventHandlersByEventName
+    delete keysToWrite.eventHandlersByNamespace
+    delete keysToWrite.configDirPath
+    delete keysToWrite.configJsonPath
+    delete keysToWrite.userInitScriptPath
+    fs.write(@configJsonPath, JSON.stringify(keysToWrite, undefined, 2) + "\n")
+
   requireUserInitScript: ->
     try
       require @userInitScriptPath if fs.exists(@userInitScriptPath)

src/app/event-emitter.coffee

@@ -31,9 +31,11 @@ module.exports =
       [eventName, namespace] = eventName.split('.')
 
       if namespace
-        @eventHandlersByNamespace?[namespace]?[eventName]?.forEach (handler) -> handler(args...)
+        if handlers = @eventHandlersByNamespace?[namespace]?[eventName]
+          new Array(handlers...).forEach (handler) -> handler(args...)
       else
-        @eventHandlersByEventName?[eventName]?.forEach (handler) -> handler(args...)
+        if handlers = @eventHandlersByEventName?[eventName]
+          handlers.forEach (handler) -> handler(args...)
 
   off: (eventName='', handler) ->
     [eventName, namespace] = eventName.split('.')