Fix GH-13177: PHP 8.3.2: final private constructor not allowed when used in trait

[nielsdos]

zend_compile has an exception to this rule for constructors using zend_is_constructor, which compares the function name to __construct. Sadly, zend_is_constructor is not a public API, but we can just do the string compare ourselves.

[iluuu1994]

trait Foo {
    private final function test() {}
}

class Bar {
    use Foo { test as __construct; }
}

class Baz extends Bar {
    public function __construct() {}
}

This emits a warning for Bar when it probably shouldn't. I'm not sure this is worth fixing, since Foo itself is already dubious.

The change itself LGTM.

[nielsdos]

This emits a warning for Bar when it probably shouldn't. I'm not sure this is worth fixing, since Foo itself is already dubious.

Let's see. In this case (with this PR) we get 2 warnings:
One for the definition in the trait.
Followed by one because test is also added to Bar. So the warning is not for __construct, but for the additional test method.
But indeed the one for test in Bar is redundant.

I pushed a fix for this to this PR, now only one warning is emitted.

[iluuu1994]

@nielsdos Oh, I wasn't aware that with as the method will be available via both symbols...

[nielsdos]

Yeah, I also used to not know this until I heard the feature is called trait aliasing, which makes sense then why it behaves that way 🙂
Anyway, the behaviour of your code snippet is now the same as it was prior to PHP 8.3: only a warning for the definition. So from a BC perspective I think the change right now makes sense.