Fatal error: Cannot redeclare humbug_phpscoper_expose_class()

[leoloso]

Bug report

Question	Answer
PHP-Scoper version	0.18.1
PHP version	8.1
Platform with version	MacOS 13
Github Repo	https://github.com/leoloso/PoP

I'm using PHP-Scoper to scope 2 WordPress plugins. When I install both of them on the same site, I get the following error:

Fatal error: Cannot redeclare humbug_phpscoper_expose_class() (previously declared in /app/wordpress/wp-content/plugins/graphql-api/vendor/scoper-autoload.php:23) in /app/wordpress/wp-content/plugins/graphql-api-pro/vendor/scoper-autoload.php on line 27

The reason is clear: both plugins define function humbug_phpscoper_expose_class in the global space.

Maybe we can append if(!function_exists('humbug_phpscoper_expose_class')) { ... when declaring the function?

For reference, this is one of my scoper.inc.php.

[leoloso]

Maybe we can append if(!function_exists('humbug_phpscoper_expose_class')) { ... when declaring the function?

Or as a possibly better solution, maybe this function should not belong to the global space?

For instance, could that function eventually change? What would happen if yet another plugin (which I don't control) also declares this function, and it uses a different version of PHP-Scoper with a different body for that function?

[leoloso]

For more info, the generated scoper-autoload.php in the first plugin includes this code:

// Class aliases. For more information see:
// https://github.com/humbug/php-scoper/blob/master/docs/further-reading.md#class-aliases
function humbug_phpscoper_expose_class(string $exposed, string $prefixed): void {
    if (!class_exists($exposed, false) && !interface_exists($exposed, false) && !trait_exists($exposed, false)) {
        spl_autoload_call($prefixed);
    }
}
humbug_phpscoper_expose_class('ComposerAutoloaderInit273da6432bdd2a4760f81baa5edeef91', 'PrefixedByPoP\ComposerAutoloaderInit273da6432bdd2a4760f81baa5edeef91');
humbug_phpscoper_expose_class('�', 'PrefixedByPoP\�');
humbug_phpscoper_expose_class('JsonException', 'PrefixedByPoP\JsonException');
humbug_phpscoper_expose_class('ValueError', 'PrefixedByPoP\ValueError');
humbug_phpscoper_expose_class('PhpToken', 'PrefixedByPoP\PhpToken');
humbug_phpscoper_expose_class('Stringable', 'PrefixedByPoP\Stringable');
humbug_phpscoper_expose_class('Attribute', 'PrefixedByPoP\Attribute');
humbug_phpscoper_expose_class('UnhandledMatchError', 'PrefixedByPoP\UnhandledMatchError');
humbug_phpscoper_expose_class('CastToType', 'PrefixedByPoP\CastToType');

And for the 2nd plugin:

// Class aliases. For more information see:
// https://github.com/humbug/php-scoper/blob/master/docs/further-reading.md#class-aliases
function humbug_phpscoper_expose_class(string $exposed, string $prefixed): void {
    if (!class_exists($exposed, false) && !interface_exists($exposed, false) && !trait_exists($exposed, false)) {
        spl_autoload_call($prefixed);
    }
}
humbug_phpscoper_expose_class('ComposerAutoloaderInit89cbc2fda26b6381875b47bf0ef5ef0b', 'PrefixedByPoPPRO\ComposerAutoloaderInit89cbc2fda26b6381875b47bf0ef5ef0b');

[theofidry]

Ha I didn't think of this case. I think it makes sense to wrap the function declaration in a if(!function_exists()) statement.

Or as a possibly better solution, maybe this function should not belong to the global space?

Technically possible, but a bit annoying in this specific case. At the very least it's more boiler-template so I wanted to avoid it.

For instance, could that function eventually change? What would happen if yet another plugin (which I don't control) also declares this function, and it uses a different version of PHP-Scoper with a different body for that function?

If it really comes to this, then indeed I'll have to introduce a namespace for it. But as an end-user you should not be affected. Also note that this function is internal, maybe I should prefix it with _...