php - 为什么 composer install --no-dev 不起作用？

Question

我正在开发一个包库，它具有常规依赖项和一个开发依赖项。 Composer recommends to not include the composer.lock file for libraries ，所以这里是 composer.json

{
    "name": "myself/mypackage",
    "require": {
        "php": ">=5.6",
        "nesbot/carbon": "~1.20"
    },
    "require-dev": {
        "phpunit/phpunit": "^6.0"
    }
}

我希望它与运行 PHP 5.6 的应用程序兼容，并且我想使用需要 PHP 7 的最新 PHPUnit 测试工具来开发它。

在 travis 持续集成测试服务器上，我有一个在 PHP > 7 上运行 PHPUnit 测试的构建矩阵和一个 linting 脚本:

composer install
./lint-php.bash
phpunit

在 PHP < 7 上，只需 lint 源代码:

composer install --no-dev
./lint-php.bash

但是，它失败了，因为它忽略了 --no-dev 标志并尝试安装 dev 依赖项。

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - phpunit/phpunit 6.0.7 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.6 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.5 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.4 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.3 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.2 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.1 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - phpunit/phpunit 6.0.0 requires php ^7.0 -> your PHP version (5.6.5) does not satisfy that requirement.
    - Installation request for phpunit/phpunit ^6.0 -> satisfiable by phpunit/phpunit[6.0.0, 6.0.1, 6.0.2, 6.0.3, 6.0.4, 6.0.5, 6.0.6, 6.0.7].

为什么它会忽略 --no-dev 标志？我只是想让它安装我的常规依赖项并忽略 require-dev 部分。

Answer 1

尽管 recommendation , 这是因为你没有 composer.lock 文件，实际上是 a requested feature .

首先，它会尝试解决所有 依赖项。如果失败，它将中止。接下来，它运行实际安装，并在那时忽略开发依赖性。你的问题是无法通过第一步解决。所以并不是它忽略了 --no-dev 标志，它只是从未做到那么远。

选项 1

如果您包含一个 composer.lock 文件，那么它会跳过依赖项解析并直接进行安装，此时它将跳过开发依赖项。

选项 2

由于您不包括一个库，而是一个可执行工具，那么与其解决您以后可能包括的其他开发工具之间的潜在依赖冲突，不如将其完全从 Composer 中拉出并使用 phive (The PHAR Installation and Verification Environment) .