From: tom at r dot je
Operating system: any
PHP version: 7.2.3
Package: Reflection related
Bug Type: Bug
Bug description:is_a does not accept scalar types
Description:
------------
I cannot easily work out whether a function can be successfully called
with a given set of values if there are scalar type hints.
Ideally I'd like to do this:
<?php
function foo(string $a, callable $bar) {
}
//I want to check to see whether these arguments can be used to call the
function
$arguments = [123, 'not-callable!'];
//Or these valid arguments
// $arguments = ['A string', function() {}]; //This should pass the
check
// To do this, I need to check to see whether the arguments match the
type hint
$reflect = new ReflectionFunction('foo');
$valid = true;
foreach ($reflect->getParameters() as $i => $param) {
if ($param->getType()) {
//check to see if the type $arguments[$i] matches the type hint
//e.g. would evaluate to is_a('string', 123);
if (!is_a($param->getType()->getName(), $arguments[$i])) $valid =
false;
}
}
echo $valid ? 'Function foo can be called with supplied $arguments' :
'$arguments do not match function definition.';
?>
However, because is_a does not allow scalar types in the first argument,
it's not possible. Instead, I need to do this:
<?php
function foo(string $a, callable $bar) {
}
//I want to check to see whether these arguments can be used to call the
function
$arguments = [123, 'not-callable!'];
//Or these valid arguments
// $arguments = ['A string', function() {}]; //This should pass the
check
// To do this, I need to check to see whether the arguments match the
type hint
$reflect = new ReflectionFunction('foo');
$valid = true;
foreach ($reflect->getParameters() as $i => $param) {
if ($param->getType()) {
$type = $param->getType()->getName();
if ($type == 'string' && !is_string($arguments[$i])) $valid = false;
else if ($type == 'int' && !is_int($arguments[$i])) $valid = false;
else if ($type == 'callable' && !is_callable($arguments[$i])) $valid =
false;
else if ($type == 'array' && !is_array($arguments[$i])) $valid =
false;
}
}
echo $valid ? 'Function foo can be called with supplied $arguments' :
'$arguments do not match function definition.';
?>
Or, alternatively, this hacky as hell workaround:
<?php
function foo(string $a, callable $bar) {
}
//I want to check to see whether these arguments can be used to call the
function
$arguments = [123, 'not-callable!'];
//Or these valid arguments
// $arguments = ['A string', function() {}]; //This should pass the
check
// To do this, I need to check to see whether the arguments match the
type hint
$reflect = new ReflectionFunction('foo');
$valid = true;
foreach ($reflect->getParameters() as $i => $param) {
if ($param->getType()) {
if (!call_user_func('is_' . $param->getType()->getName(),
$arguments[$i])) $valid = false;
}
}
echo $valid ? 'Function foo can be called with supplied $arguments' :
'$arguments do not match function definition.';
?>
Ideally, is_a should support scalar types but perhaps adjusting
reflection to allow $param->getType()->willAccept($value); or similar
would work as well because at the moment, to determine this, we need to
do two checks: One for $param->getClass() and another for
$param->getType()
--
Edit bug report at https://bugs.php.net/bug.php?id=76054&edit=1
--
Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=76054&r=trysnapshot54
Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=76054&r=trysnapshot55
Try a snapshot (trunk): https://bugs.php.net/fix.php?id=76054&r=trysnapshottrunk
Fixed in SVN: https://bugs.php.net/fix.php?id=76054&r=fixed
Fixed in release: https://bugs.php.net/fix.php?id=76054&r=alreadyfixed
Need backtrace: https://bugs.php.net/fix.php?id=76054&r=needtrace
Need Reproduce Script: https://bugs.php.net/fix.php?id=76054&r=needscript
Try newer version: https://bugs.php.net/fix.php?id=76054&r=oldversion
Not developer issue: https://bugs.php.net/fix.php?id=76054&r=support
Expected behavior: https://bugs.php.net/fix.php?id=76054&r=notwrong
Not enough info: https://bugs.php.net/fix.php?id=76054&r=notenoughinfo
Submitted twice: https://bugs.php.net/fix.php?id=76054&r=submittedtwice
register_globals: https://bugs.php.net/fix.php?id=76054&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=76054&r=php4
Daylight Savings: https://bugs.php.net/fix.php?id=76054&r=dst
IIS Stability: https://bugs.php.net/fix.php?id=76054&r=isapi
Install GNU Sed: https://bugs.php.net/fix.php?id=76054&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=76054&r=float
No Zend Extensions: https://bugs.php.net/fix.php?id=76054&r=nozend
MySQL Configuration Error: https://bugs.php.net/fix.php?id=76054&r=mysqlcfg