Laravel：您的要求無法解析爲可安裝的一組套件

我試圖使用作曲者更新來更新Laravel。我正在按照指南https://laravel.com/docs/5.4/upgrade，但在運行作曲家更新時遇到困難。Laravel：您的要求無法解析爲可安裝的一組套件

*注意：我沒有「bootstrap/cache/compiled.php」。

{ 
"name": "laravel/laravel", 
"description": "The Laravel Framework.", 
"keywords": ["framework", "laravel"], 
"license": "MIT", 
"type": "project", 
"require": { 
    "php": ">=5.5.9", 
    "laravel/framework": "5.4.*", 
    "illuminate/html": "5.0.*", 
    "laravelcollective/html": "5.2.*" 
}, 
"require-dev": { 
    "fzaninotto/faker": "~1.4", 
    "mockery/mockery": "0.9.*", 
    "phpunit/phpunit": "~5.7", 
    "symfony/css-selector": "2.8.*|3.0.*", 
    "symfony/dom-crawler": "2.8.*|3.0.*" 
}, 
"autoload": { 
    "classmap": [ 
     "database" 
    ], 
    "psr-4": { 
     "App\\": "app/" 
    } 
}, 
"autoload-dev": { 
    "classmap": [ 
     "tests/TestCase.php" 
    ] 
}, 
"scripts": { 
    "post-root-package-install": [ 
     "php -r \"copy('.env.example', '.env');\"" 
    ], 
    "post-create-project-cmd": [ 
     "php artisan key:generate" 
    ], 
    "post-install-cmd": [ 
     "php artisan clear-compiled", 
     "php artisan optimize" 
    ], 
    "pre-update-cmd": [ 
     "php artisan clear-compiled" 
    ], 
    "post-update-cmd": [ 
     "php artisan optimize" 
    ] 
}, 
"config": { 
    "preferred-install": "dist" 
} 
}

控制檯拋出了以下錯誤：