TypeDoesNotContainType - handle PHP type toggles

[SpacePossum]

Hi all,

https://psalm.dev/r/1944680e7d

<?php

function closeFile($file)
{
    fclose($file);
}

$file = fopen(__FILE__, 'r');

if (false === $file) {
    throw new \RuntimeException('foo');
}

echo "\n".gettype($file);

closeFile($file);

echo "\n".gettype($file);

if (!is_resource($file)) {
    echo "\nNot a resource";
}

output:

$ php var/tmp/psalm/test2.php 

resource
resource (closed)
Not a resource

ERROR: TypeDoesNotContainType - 20:6 - Found a contradiction when evaluating $file and trying to reconcile type 'resource' to !resource

I think this error is not correct. When running the code the type of $file becomes resource when opened and gets changed to resource (closed) because of the fclose call on it. As such the !is_resource check seems valid.

The example code is over simplified, a production sample I've got is when guzzle closes the file handle on successful download.

[muglug]

WTF PHP

[SpacePossum]

This variant also invalid triggers;

ERROR: RedundantCondition - var/tmp/psalm/test2.php:21:5 - Found a redundant condition when evaluating $file and trying to reconcile type 'resource' to resource
if (is_resource($file)) {

<?php

function closeFile($file)
{
    fclose($file);
}


$file = fopen(__FILE__, 'r');

if (false === $file) {
    throw new \RuntimeException('');
}

try {
    closeFile($file);
} catch (\Exception $e) {
    throw $e;
}

if (is_resource($file)) {

} else {
    echo 'not an resource';
}

[SpacePossum]

yeah, the type juggling of PHP with resources is ... ehmmm.. a bit of a pain for SCA : (

[muglug]

This is truly insane