Throwable interface problems in namespaces

[jurchiks]

test.php:

<?php
namespace test;

function a(\Throwable $t) {}

a(new \RuntimeException('foo'));

$ hhvm --no-config -d hhvm.php7.all=true test.php

Fatal error: Uncaught TypeError: Argument 1 passed to test\a() must be an instance of Throwable, RuntimeException given in /home/jsudmalis/test.php:6
Stack trace:
#0 /home/jsudmalis/test.php(8): test\a()
#1 {main}

It seems HHVM does not recognise Throwable inside a namespace. Since this is a class in __SystemLib, I'm worried this might be an issue with other classes there.

[fredemmott]

-d hhvm.php7.all=true needs to go before test.php, otherwise it goes into test.php's argv instead of being considered an HHVM option:

 hhvm --no-config -d hhvm.php7.all=true test.php
bool(false)
bool(true)
bool(true)

So RuntimeException does implement Throwable. interface_exists() fails because:

<?php
var_dump(interface_exists('Throwable'));
var_dump(interface_exists(Throwable::class));
var_dump(Throwable::class);
[fredemmott@devbig349 ~/test] hhvm --no-config -d hhvm.php7.all=true test.php
bool(false)
bool(true)
string(21) "__SystemLib\Throwable"

Also an issue, but probably much less important.

[fredemmott]

heh, that's pretty bad D: we need to not auto-import it into the current namespace (like we do for hack stuff), but actually alias it.

[jurchiks]

@fredemmott cleaned my comments up a bit, you can delete your first one as well, to keep the topic brief.

[fredemmott]

Keeping it in, the Throwable::class vs 'Throwable' vs \Throwable could be useful for whoever works on this.

[fredemmott]

https://3v4l.org/fKiQ3

<?php

namespace Foo;

$x = new \Exception();
var_dump($x instanceof \Throwable);