AliasSpecification::resolveAlias implementation bug

[Florian-agora]

I got an issue upgrading from 1.7 to the latest version.

After investigation, it appears to come from AliasSpecification::resolveAlias.

private function resolveAlias(string $symbol): string
    {
        $aliases = PhpParser::parseUseStatements($this->reflection);

        if (in_array($symbol, $aliases, true)) {
            return $symbol;
        }

        $namespaceParts = explode('\\', $symbol);

        $alias = strtolower(array_shift($namespaceParts));

        if (! isset($aliases[$alias])) {
            return $symbol;
        }

        if ($namespaceParts === []) {
            return $aliases[$alias];
        }

        return $aliases[$alias] . '\\' . implode('\\', $namespaceParts);
    }

First the method does $aliases = PhpParser::parseUseStatements($this->reflection);, which is an array with the class / alias as the key.

Then it checks if the alias from $alias = strtolower(array_shift($namespaceParts)); is in the previous array.

Since we are not taking the last part, but the first (array_shift instead of array_pop), we are searching the known aliases from the beginning of the path, not the last part. I am pretty sure this is NOT intended, since I found a previous commit where the variable was called "lastPart" instead.

[romm]

Hi @Florian-agora thanks for the report. 😊

Could you post a snippet that reproduces the error?

[Florian-agora]

Simply declare 2 classes in the same namespace which use another class which name matches the root of the namespace.

<?php

namespace A\B;

use A\B\A; // this will trigger the bug

// can be in another file, but must me implicitly imported (same namespace)
class Bar 
{
    public function __construct(
        public string $bar
    ) {
    }
}

class Foo
{
    public function __construct(
        public Bar $foo,
    ) {
    }
}

Then when trying to map something to class Foo, the Bar class will not be found

// this results in  "Reflection.php line 60: Class "A\B\A\B" does not exist"
$foo = (new MapperBuilder())
                ->mapper()
                ->map(Foo::class, Source::json('{ "foo": "foo!"}'))
            ;