Missing trait causes fatal error unlike a missing interface or parent class

[alexpott]

Description

The following code:

<?php
class A {
    use MissingTrait;
}

Resulted in this output:

Fatal error: Trait "MissingTrait" not found in /in/QPqKX on line 3

Process exited with code 255.

But I expected this output instead:

Fatal error: Uncaught Error: Trait "MissingTrait" not found in /in/QPqKX on line 3
Stack trace:
#0 {main}
  thrown in /in/bSnmM on line 3

Process exited with code 255.

PHP Version

8.2.0 - 8.2.27, 8.3.0 - 8.3.17, 8.4.1 - 8.4.4

Operating System

No response

[alexpott]

Compare with the behaviour for a missing class.

<?php

class A extends Missing {
    
}

produces:

Fatal error: Uncaught Error: Class "Missing" not found in /in/bSnmM:3
Stack trace:
#0 {main}
  thrown in /in/bSnmM on line 3

Process exited with code 255.

[alexpott]

Or interface

<?php

class A implements MissingInterface {
    
}

produces:

Fatal error: Uncaught Error: Interface "MissingInterface" not found in /in/UV6mc:3
Stack trace:
#0 {main}
  thrown in /in/UV6mc on line 3

Process exited with code 255.

[iluuu1994]

I would call this a feature rather than a bug. Recovering from inheritance errors can lead to subtle issues. It should almost certainly be fine here since this error occurs before the interface one, but this should still land in master and not in active branches.

[alexpott]

@iluuu1994 thanks! Your fix looks great!