scoper-autoload.php using class_exists for scoped interfaces

[jarrodbell]

Bug report

Question	Answer
Box version	0.13.3
PHP version	7.2.29
Platform with version	MacOS

scoped output of vendor/symfony/polyfill-php70/Resources/stubs/SessionUpdateTimestampHandlerInterface.php

<?php

namespace MyNamespace;

interface SessionUpdateTimestampHandlerInterface
{
    /**
     * Checks if a session identifier already exists or not.
     *
     * @param string $key
     *
     * @return bool
     */
    public function validateId($key);
    /**
     * Updates the timestamp of a session when its data didn't change.
     *
     * @param string $key
     * @param string $val
     *
     * @return bool
     */
    public function updateTimestamp($key, $val);
}
\class_alias('MyNamespace\\SessionUpdateTimestampHandlerInterface', 'SessionUpdateTimestampHandlerInterface', \false);

scoper-autoload.php contains the following snippet:

if (!class_exists('SessionUpdateTimestampHandlerInterface', false)) {
    class_exists('MyNamespace\SessionUpdateTimestampHandlerInterface');
}

The above results in an error:

Cannot declare interface SessionUpdateTimestampHandlerInterface, because the name is already in use

vendor/symfony/polyfill-php70/Resources/stubs/SessionUpdateTimestampHandlerInterface.php:25
class_alias()
vendor/symfony/polyfill-php70/Resources/stubs/SessionUpdateTimestampHandlerInterface.php:25
Composer\A\includeFile()
vendor/composer/ClassLoader.php:322
Composer\A\ClassLoader->loadClass()
Unknown location
spl_autoload_call()
Unknown location
class_exists('MyNamespace\SessionUpdateTimestampHandlerInterface')
vendor/scoper-autoload.php:25

If I change the scoper-autoload.php snippet above to the following instead, the error is gone:

if (!interface_exists('SessionUpdateTimestampHandlerInterface', false)) {
    interface_exists('MyNamespace\SessionUpdateTimestampHandlerInterface');
}

Is there something I am missing to make sure scoper-autoload.php correctly uses interface_exists for Interfaces?

[discordier]

Problem got introduced in #340.

I'd love to solve this, however, we do not know what the passed class-string is.

Therefore the only possible solution that pops into my mind is by swapping the guard with this:

return sprintf(
    <<<'PHP'
if (!class_exists('%1$s', false) && !interface_exists('%1$s', false) && !trait_exists('%1$s', false)) {
    spl_autoload_call('%2$s');
}
PHP
    ,
    $originalClass,
    $prefixedClass
);

[theofidry]

Ugh that makes me wonder how the trait whitelisting is supported right now (I don't think it is).

Otherwise I think your solution is pretty good: it's a lot easier than registering the type to the whitelist too (which would be nice but is a non negligible amount of work) 👍

[discordier]

Ugh that makes me wonder how the trait whitelisting is supported right now (I don't think it is).

I sadly lack a trait from global namespace, so I really can't tell. We'll to test that one separately I guess, however I think it won't hurt supporting it already here and leave it to the other implementation parts of the scoper to catch up later.

Otherwise I think your solution is pretty good: it's a lot easier than registering the type to the whitelist too (which would be nice but is a non negligible amount of work)

This is why I refrained from transporting multiple lists of classes, interfaces and traits (and maybe in future who knows what else might appear).

To put long story short, my throw at it is in #417