[PHP-BUG] Bug #74349 [NEW]: cannot use include return string in OR condition

From:             liviu dot gelea at gmail dot com
Operating system: Windows 10
PHP version:      7.1.3
Package:          Filesystem function related
Bug Type:         Bug
Bug description:cannot use include return string in OR condition

Description:
------------
When "returning" a string from a file, the result behaves differently if
used in a condition containing the  || operator

setup an "environment.php" file that contains:

<?php 
return "production";

then run the script attached:

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

// determine application environment
$environmentFile = 'environment.php';
if (!file_exists($environmentFile)) {
    $environment = 'development';
} elseif ($environment = include $environmentFile) {
    // do nothing
} else {
    $environment = 'development';
}

echo $environment . " ";

if (!file_exists($environmentFile) || ($environment = include
$environmentFile)) {
    $environment = 'development';
}

echo $environment;

Expected result:
----------------
the script should echo the string
"production production"

Actual result:
--------------
"production development"

-- 
Edit bug report at https://bugs.php.net/bug.php?id=74349&edit=1
-- 
Try a snapshot (PHP 5.4):   https://bugs.php.net/fix.php?id=74349&r=trysnapshot54
Try a snapshot (PHP 5.5):   https://bugs.php.net/fix.php?id=74349&r=trysnapshot55
Try a snapshot (trunk):     https://bugs.php.net/fix.php?id=74349&r=trysnapshottrunk
Fixed in SVN:               https://bugs.php.net/fix.php?id=74349&r=fixed
Fixed in release:           https://bugs.php.net/fix.php?id=74349&r=alreadyfixed
Need backtrace:             https://bugs.php.net/fix.php?id=74349&r=needtrace
Need Reproduce Script:      https://bugs.php.net/fix.php?id=74349&r=needscript
Try newer version:          https://bugs.php.net/fix.php?id=74349&r=oldversion
Not developer issue:        https://bugs.php.net/fix.php?id=74349&r=support
Expected behavior:          https://bugs.php.net/fix.php?id=74349&r=notwrong
Not enough info:            https://bugs.php.net/fix.php?id=74349&r=notenoughinfo
Submitted twice:            https://bugs.php.net/fix.php?id=74349&r=submittedtwice
register_globals:           https://bugs.php.net/fix.php?id=74349&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=74349&r=php4
Daylight Savings:           https://bugs.php.net/fix.php?id=74349&r=dst
IIS Stability:              https://bugs.php.net/fix.php?id=74349&r=isapi
Install GNU Sed:            https://bugs.php.net/fix.php?id=74349&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=74349&r=float
No Zend Extensions:         https://bugs.php.net/fix.php?id=74349&r=nozend
MySQL Configuration Error:  https://bugs.php.net/fix.php?id=74349&r=mysqlcfg