为什么 Composer 安装了似乎与要求冲突的软件包版本？

Question

这看起来是一个简单的问题，但我无法解释发生了什么。

在我的 Symfony 项目的 composer.json 中，twig 版本被指定为

php c:\php\composer\composer.phar depends -t "twig/twig"
twig/twig v2.4.3 Twig, the flexible, fast, and secure template language for PHP
|--symfony/framework-standard-edition dev-develop (requires twig/twig <2.0)
|--symfony/symfony v2.8.24 (requires twig/twig ~1.34|~2.4)
|  `--symfony/framework-standard-edition dev-develop (requires symfony/symfony 2.8.*)
`--twig/extensions v1.5.1 (requires twig/twig ~1.27|~2.0)
   `--symfony/framework-standard-edition dev-develop (requires twig/extensions ^1.3)

composer.json 的相关块：

"require": {
    "php": ">=5.3.3",
    "symfony/symfony": "2.8.*",
    "doctrine/dbal": "2.5.*",
    "doctrine/orm": "2.5.*",
    "doctrine/doctrine-bundle": "~1.2",
    "twig/twig": "<2.0",
    "twig/extensions": "^1.3",
    etc
}

在我看来，symfony/symfony 和 twig/extensions 软件包的要求与项目的要求相结合，将导致 Twig 的最高 1.x 版本 1.34.4，但事实并非如此.为什么？

编辑：

作曲家 1.4.2

完整的composer.json

{
    "name": "symfony/framework-standard-edition",
    "license": "MIT",
    "type": "project",
    "description": "The \"Symfony Standard Edition\" distribution",
    "autoload": {
        "psr-0": { "": "src/", "SymfonyStandard": "app/" }
    },
    "require": {
        "php": ">=5.3.3",
        "symfony/symfony": "2.8.*",
        "doctrine/dbal": "2.5.*",
        "doctrine/orm": "2.5.*",
        "doctrine/doctrine-bundle": "~1.2",
        "twig/twig": "<2.0",
        "twig/extensions": "^1.3",
        "symfony/assetic-bundle": "^2.8",
        "symfony/swiftmailer-bundle": "~2.3",
        "symfony/monolog-bundle": "~2.4",
        "sensio/distribution-bundle": "~3.0",
        "sensio/framework-extra-bundle": "~3.0",
        "incenteev/composer-parameter-handler": "~2.0",
        "beberlei/DoctrineExtensions": "^1.0",
        "royopa/fpdf-symfony2": "^1.0",
        "liuggio/excelbundle": "^2.0",
        "patchwork/jsqueeze": "^2.0",
        "leafo/scssphp": "^0.6.5",
        "doctrine/doctrine-migrations-bundle": "^1.0",
        "ocramius/proxy-manager": "~2.0.0",
        "aws/aws-sdk-php-symfony": "^1.2"
    },
    "require-dev": {
        "sensio/generator-bundle": "~2.3",
        "symfony/phpunit-bridge": "^3.1",
        "deployer/deployer": "^3.3"
    },
    "scripts": {
        "post-root-package-install": [
            "SymfonyStandard\\Composer::hookRootPackageInstall"
        ],
        "post-install-cmd": [
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::removeSymfonyStandardFiles"
        ],
        "post-update-cmd": [
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::removeSymfonyStandardFiles"
        ]
    },
    "config": {
        "bin-dir": "bin"
    },
    "extra": {
        "symfony-app-dir": "app",
        "symfony-web-dir": "web",
        "incenteev-parameters": {
            "file": "app/config/parameters.yml"
        },
        "branch-alias": {
            "dev-master": "2.5-dev"
        }
    }
}

编辑 2：

删除 composer.lock 并完全更新和重新安装给了我我认为我应该得到的东西！

Answer 1

你用的是什么版本的作曲家？

我在 Linux Mint 17 上使用 php 5.5 和 composer 1.3.2 测试了该 json 文件，安装的 twig 版本是正确的（twig/twig - v1.34.4）。

您可以尝试粘贴完整的 composer.json 文件吗？

另外，我建议删除 composer.lock 文件和供应商文件夹的所有内容，然后再次尝试安装。