作曲家更新：您的要求无法解决为一组可安装的软件包

Question

我正在尝试从 laravel 5.5 升级到 5.6。为此，我一直在使用 upgrade guide。

首先，我尝试将 laravel/framework 更新为 5.6.* 并将 phpunit/phpunit 更新为 ~7.0。

这会产生错误 Your requirements could not be resolved to an installable set of packages.

我明白这意味着什么，但是错误日志真的很难解析，我已经尝试了几个小时来将 composer.json 文件更改为一组可安装的软件包。
我还没设法自己解决这个问题，所以我来找你。也许你们中的一些人真的喜欢解决这些问题...

所以，我目前的 composer.json，在所有的荣耀中：

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "php": ">=7.1",
        "laravel/framework": "5.6.*",
        "jenssegers/rollbar": "^1.4",
        "doctrine/dbal": "~2.3",
        "sensiolabs/security-checker": "^3.0",
        "guzzlehttp/guzzle": "~6.0",
        "mandrill/mandrill": "1.0.*",
        "lcobucci/jwt" : "^3.1",
        "predis/predis": "~1.0"
    },
    "require-dev": {
        "fzaninotto/faker": "~1.4",
        "mockery/mockery": "0.9.*",
        "phpunit/phpunit": "~7.0",
        "phpspec/phpspec": "~4.0",
        "laravel/homestead" : "~4.0",
        "symfony/dom-crawler": "3.1.*",
        "symfony/css-selector": "3.1.*",
        "filp/whoops": "~2.0"
    }
}

而当前错误：

➔ composer update
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Conclusion: don't install laravel/framework v5.6.15
    - Conclusion: don't install laravel/framework v5.6.14
    - Conclusion: don't install symfony/process v4.0.7
    - Conclusion: don't install laravel/framework v5.6.13
    - Conclusion: don't install symfony/process v4.0.6
    - Conclusion: don't install symfony/process v4.0.5
    - Conclusion: don't install symfony/process v4.0.4
    - Conclusion: don't install symfony/process v4.0.3
    - Conclusion: don't install symfony/process v4.0.2
    - Installation request for laravel/homestead ~4.0 -> satisfiable by laravel/homestead[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5].
    - Conclusion: don't install symfony/process v4.0.1
    - laravel/framework v5.6.0 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.1 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.10 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.11 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.12 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.2 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.3 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.4 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.5 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.6 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.7 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.8 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - laravel/framework v5.6.9 requires symfony/process ~4.0 -> satisfiable by symfony/process[v4.0.0, v4.0.1, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6, v4.0.7].
    - Conclusion: don't install symfony/process v4.0.0
    - Installation request for laravel/framework 5.6.* -> satisfiable by laravel/framework[v5.6.0, v5.6.1, v5.6.10, v5.6.11, v5.6.12, v5.6.13, v5.6.14, v5.6.15, v5.6.2, v5.6.3, v5.6.4, v5.6.5, v5.6.6, v5.6.7, v5.6.8, v5.6.9].

我真的希望有人能够破译作曲家在这里的意思。我也很想自己也能做到这一点，但似乎同一个问题的所有其他解决方案都是专门针对 that composer.json 的，而不是一般的回答..

Answer 1

对于这种情况，我必须执行以下操作：

我将 php 更新为 ^7.1.3
sensiolabs/security-checker 到 ^4.1
phpspec 到 ~4.0
laravel/homestead 到 ~7.3
symfony/dom-crawler 和 symfony/css-selector 到 ^4.0
删除对 composer optimize 的引用，因为现在已删除
停止使用 configureMonologUsing(...) 并为 Rollbar 创建自定义记录器 class。

感谢评论中的所有帮助！

作曲家更新：您的要求无法解决为一组可安装的软件包

composer update: Your requirements could not be resolved to an installable set of packages

php

symfony

laravel

composer-php

laravel-5.6