How to constraint compatibility with PHP without explicitly constraint all the depending packages

问题

I got this requirement in my composer.json:

"php": ">= 5.6",
"symfony/http-foundation": "^3.0"

The problem with that configuration is that it will install paragonie/random_compat v9.99.99 which is only compatible with PHP 7 and more. But the thing is that I don't want my composer.lock file to require PHP 7, I want it to still be compatible with PHP 5.6.

The solution I found is to track down which package was pulling this dependency and, once I found it, I added this to my requirements:

"paragonie/random_compat": "~2.0"

But I wonder if there is not a better way of doing that: somehow telling that I accept all the versions above PHP 5.6, but I don't accept packages that would force to have PHP 7?

回答1:

If you want to make composer.lock compatible with PHP 5.6, you have at least two options to achieve that:

1. Use PHP 5.6 for composer update - you should be able to install multiple versions of PHP on your OS and run Composer like this:

   /path/to/php6.5 /path/to/composer update
   

2. Use platform settings in composer.json to force installation for specific version regardless PHP version used to run Composer commands:

   "config": {
       "platform": {
           "php": "5.6.38"
       }
   },
   

来源：https://stackoverflow.com/questions/52355467/how-to-constraint-compatibility-with-php-without-explicitly-constraint-all-the-d