False positive for array_filter #3559
Description
Consider the following example:
$f = function (...$args): void {
foreach (array_filter($args) as $k => $v) {}
};We know that $args is an array, so array_filter($args) must be an array also, but PHPStan warns that it could be null, incorrectly:
Argument of an invalid type (array|null) supplied for foreach, only iterables are supported.
The full context in which this was discovered:
/**
* @param mixed $value as passed via Request transfer options.
*/
private function add_debug(RequestInterface $request, array &$options, $value, array &$params): void
{
if ($value === false) {
return;
}
static $map = [
\STREAM_NOTIFY_CONNECT => 'CONNECT',
\STREAM_NOTIFY_AUTH_REQUIRED => 'AUTH_REQUIRED',
\STREAM_NOTIFY_AUTH_RESULT => 'AUTH_RESULT',
\STREAM_NOTIFY_MIME_TYPE_IS => 'MIME_TYPE_IS',
\STREAM_NOTIFY_FILE_SIZE_IS => 'FILE_SIZE_IS',
\STREAM_NOTIFY_REDIRECTED => 'REDIRECTED',
\STREAM_NOTIFY_PROGRESS => 'PROGRESS',
\STREAM_NOTIFY_FAILURE => 'FAILURE',
\STREAM_NOTIFY_COMPLETED => 'COMPLETED',
\STREAM_NOTIFY_RESOLVE => 'RESOLVE',
];
static $args = ['severity', 'message', 'message_code',
'bytes_transferred', 'bytes_max'];
$value = Utils::debugResource($value);
$ident = $request->getMethod() . ' ' . $request->getUri()->withFragment('');
self::addNotification(
$params,
static function (int $code, ...$passed) use ($ident, $value, $map, $args): void {
\fprintf($value, '<%s> [%s] ', $ident, $map[$code]);
foreach (\array_filter($passed) as $i => $v) {
\fwrite($value, $args[$i] . ': "' . $v . '" ');
}
\fwrite($value, "\n");
}
);
} ------ ---------------------------------------------------------------------
Line Handler/StreamHandler.php
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544 Argument of an invalid type (array|null) supplied for foreach, only
iterables are supported.
------ ---------------------------------------------------------------------