What is the problem of connecting the trait?

Question

PHP

src\Controllers\Commands.php:

namespace Project\Controllers;

use Library\SubDir\Traits\Trait;

class Commands
{
    use Trait;

...

autoload_psr4.php:

'Library\\SubDir\\' => array($vendorDir . '/library/name/src'),

Trait.php is located in the external package. /library/name/src/Traits/Trait.php

At the same time, it works inside the external package, and when trying to connect the trait to the project, an error about the trait not found:

Fatal error: Trait "Library\SubDir\Traits\Trait" not found in /project/src/Controllers/Commands.php on line 8

Update:

/library/name/src/Traits/Trait.php:

namespace Library\SubDir\Traits;

use Library\SubDir\Api;

trait Trait
{
...

Answer 1

The problem was in the specifics of the package, where for the trait to work correctly, you need to set certain properties for it.