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Bug #74478 null coalescing operator failing with SplFixedArray
Submitted: 2017-04-20 11:56 UTC Modified: 2017-04-20 16:08 UTC
From: dariusz dot ruminski at gmail dot com Assigned: jhdxr (profile)
Status: Closed Package: SPL related
PHP Version: 7.1.4 OS: Windows
Private report: No CVE-ID: None
 [2017-04-20 11:56 UTC] dariusz dot ruminski at gmail dot com
Description:
------------
When I use null coalescing operator on a class implementing SplFixedArray then offsetExists is not called, but offsetGet is called instead (which may trigger some error). It should be equivalent to ternary operator with isset.

This is similar to https://bugs.php.net/bug.php?id=71731 (here - SplFixedArray, there - ArrayAccess).

https://3v4l.org/#v714


Test script:
---------------
<?php

$arrayData = new class implements \ArrayAccess
{
	public function offsetExists($offset)
	{
		echo "offsetExists\n";
	}


	public function offsetGet($offset)
	{
		echo "offsetGet\n";
	}


	public function offsetSet($offset, $value)
	{
	}


	public function offsetUnset($offset)
	{
	}
};
echo "arrayData - isset:\n";
isset($arrayData['foo']) ? NULL : NULL;
echo "arrayData - null coalescing operator:\n";
$arrayData['foo'] ?? NULL;


$fixedData = new class extends \SplFixedArray
{
	public function offsetExists($offset)
	{
		echo "offsetExists\n";
	}


	public function offsetGet($offset)
	{
		echo "offsetGet\n";
	}


	public function offsetSet($offset, $value)
	{
	}


	public function offsetUnset($offset)
	{
	}

};
echo "fixedData - isset:\n";
isset($fixedData['foo']) ? NULL : NULL;
echo "fixedData - null coalescing operator:\n";
$fixedData['foo'] ?? NULL;

Expected result:
----------------
arrayData - isset:
offsetExists
arrayData - null coalescing operator:
offsetExists
fixedData - isset:
offsetExists
fixedData - null coalescing operator:
offsetExists

Actual result:
--------------
arrayData - isset:
offsetExists
arrayData - null coalescing operator:
offsetExists
fixedData - isset:
offsetExists
fixedData - null coalescing operator:
offsetGet

Patches

Pull Requests

Pull requests:

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2017-04-20 12:00 UTC] dariusz dot ruminski at gmail dot com
https://3v4l.org/BudKa
 [2017-04-20 16:08 UTC] [email protected]
-Status: Open +Status: Assigned
 [2017-04-20 16:08 UTC] [email protected]
-Assigned To: +Assigned To: jhdxr
 [2017-05-24 16:02 UTC] [email protected]
Automatic comment on behalf of jhdxr
Revision: http://git.php.net/?p=php-src.git;a=commit;h=872e43d6e55e4af84681b259198ee688287cd40d
Log: Fixed bug #74478
 [2017-05-24 16:02 UTC] [email protected]
-Status: Assigned +Status: Closed
 
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