Add support for os-families-exclude in extensions composer.json

[alexandre-daubois]

Fix #106

Allows to specify OS families which the extension is incompatible with:

{
    "name": "myvendor/myext",
    "php-ext": {
        "extension-name": "myext",
        "configure-options": [
            // ...
        ],
        "os-families-exclude": ['Windows', 'Darwin']
    }
}

When the syntax is validated, I'll create a PR in Composer to allow the new key in the Package::$phpExt property.

Related to ThePHPF/pie-design#29

[asgrim]

This must use the TargetPlatform; since users of PIE can install a package for a different version of PHP than the one running PIE

[alexandre-daubois]

That's what I thought first. Does it mean that user can even build and install extensions for a different OS than the one running Pie with a cross compilation system?

[asgrim]

In practice, at the moment, no. Theoretically, it would be possible to change various command invocations and file operations to run against a remote PHP install. But, that hasn't been discussed though as whether it's something we even want to do.

[alexandre-daubois]

Right thanks, I'll do the update 👍

[asgrim]

should be a list<OsFamily> and create a new enum for this with the allowed values:

• Windows
• BSD
• Darwin
• Solaris
• Linux
• Unknown

ref: https://www.php.net/manual/en/reserved.constants.php#constant.php-os-family

[alexandre-daubois]

Revamped the whole PR to address your comments.

• Things are done in ResolveDependencyWithComposer instead of CommandHelper
• An enum holding OS families is added
• It is added to the TargetPlatform
• PhpBinaryPath is used to determine the OS family, just like the OS