Composer更新不安装整个Laravel应用程序

Fatal error: Class 'IlluminateSupportArr' not found in
/home/forge/toono.co/vendor/laravel/framework/src/Illuminate/Support/helpers.php
on line 151

这是在运行composer update命令之后.我已经通过SSH进入目录并且低,看,文件Arr.php不存在.

代码从BitBucket中的主分支中提取,然后在生产服务器上执行以下行：

cd /home/forge/default
git pull origin master
composer install
php artisan migrate --force

Composer.json：

{
    "name": "laravel/laravel","description": "The Laravel Framework.","keywords": [
        "framework","laravel"
    ],"license": "MIT","require": {
        "laravel/framework": "4.2.*"
    },"require-dev": {
        "way/generators": "2.*","fzaninotto/faker": "1.4.*@dev","barryvdh/laravel-debugbar": "1.*","flynsarmy/csv-seeder": "1.0.*"
    },"autoload": {
        "classmap": [
            "app/commands","app/controllers","app/models","app/database/migrations","app/database/seeds","app/tests/TestCase.php"
        ]
    },"scripts": {
        "post-install-cmd": [
            "php artisan clear-compiled","php artisan optimize"
        ],"post-update-cmd": [
            "php artisan clear-compiled","php artisan debugbar:publish","post-create-project-cmd": [
            "php artisan key:generate"
        ]
    },"config": {
        "preferred-install": "dist"
    },"minimum-stability": "stable"
}

Composer.lock：

"require": {
    "codesleeve/stapler": "~1","laravel/framework": "~4","php": ">=5.4.0"
}

为什么作曲家更新错过了那个文件？在本地更新后甚至在Github的主分支上,Arr.php在那里？

如果我遗漏了您需要的任何必要代码,请告诉我.

任何帮助将不胜感激.