Laravel：您的要求无法解决为一组可安装的软件包

Question

我正在尝试使用composer update来更新Laravel。 我正在遵循https://laravel.com/docs/5.4/upgrade上的指南，但是在运行作曲家更新时会陷入困境。

*注意：我没有“ bootstrap / cache / compiled.php”。

我已经更新了composer.json，如下所示：

{
"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"
}
}

控制台引发以下错误：

Answer 1

您的laravelcollective软件包指向需要<= 5.2。*的Laravel Core

手动更新它，然后重新运行它：

"laravelcollective/html": "^5.4.0"