Bug #71217 [Com]: foreach() with inline assignment doesn't keep references

Edit report at https://bugs.php.net/bug.php?id=71217&edit=1

 ID:                 71217
 Comment by:         php at etc dot chkgo dot com
 Reported by:        bugs dot php dot net at ss dot st dot tc
 Summary:            foreach() with inline assignment doesn't keep
                     references
 Status:             Open
 Type:               Bug
 Package:            Scripting Engine problem
 Operating System:   Linux, OSX
 PHP Version:        7.0.1
 Block user comment: N
 Private report:     N

 New Comment:

Faced the same problem in a part of function results assignment right in foreach and changing iterated items by reference. Got unexpected behavior on PHP 7.0.0 and 7.0.1 but seemed working fine on 5.6. /Gentoo

So it was pretty much as described in the ticket. My vote.


Previous Comments:
------------------------------------------------------------------------
[2015-12-24 20:07:43] bugs dot php dot net at ss dot st dot tc

Description:
------------
When an inline assignment of array_expression is done right in foreach() statement, all further references to iterated array items seem to become their copies.

I believe both PHP 5.6 and 7 are affected, yet still they behave differently.
Tested on PHP 5.6.12, 5.6.16, 7.0.0, 7.0.1.


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

# source array
$source = [ 'subarray' => ['item' => 'old value ---'] ];


# $ref1 is assigned to $source right in the foreach()
foreach ( $ref1 = $source as &$subarray ) {
	$subarray['item'] = 'NEW value';
	echo $subarray['item'], PHP_EOL;
	echo $ref1['subarray']['item'], PHP_EOL;
}
echo PHP_EOL;


# $ref2 is assigned to $source normally, as a separate operation
$ref2 = $source;
foreach ( $ref2 as &$subarray ) {
	$subarray['item'] = 'NEW value';
	echo $subarray['item'], PHP_EOL;
	echo $ref2['subarray']['item'], PHP_EOL;
}
echo PHP_EOL;


########################################

# similar to $source array, but implemented using a function
function getSource() {
	return [ 'subarray' => ['item' => 'old value ---'] ];
}


# $ref3 is assigned to result of getSource() right in the foreach()
foreach ( $ref3 = getSource() as &$subarray ) {
	$subarray['item'] = 'NEW value';
	echo $subarray['item'], PHP_EOL;
	echo $ref3['subarray']['item'], PHP_EOL;
}
echo PHP_EOL;


# $ref4 is a "normal" reference to a result of getSource()
$ref4 = getSource();
foreach ( $ref4 as &$subarray ) {
	$subarray['item'] = 'NEW value';
	echo $subarray['item'], PHP_EOL;
	echo $ref4['subarray']['item'], PHP_EOL;
}

Expected result:
----------------
both PHP 5 and 7:

NEW value
NEW value

NEW value
NEW value

NEW value
NEW value

NEW value
NEW value

Actual result:
--------------
PHP 7: 

NEW value
old value ---

NEW value
NEW value

NEW value
old value ---

NEW value
NEW value


PHP 5:

NEW value
old value ---

NEW value
NEW value

NEW value
NEW value

NEW value
NEW value


------------------------------------------------------------------------



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Edit this bug report at https://bugs.php.net/bug.php?id=71217&edit=1