[PHP-BUG] Bug #70618 [NEW]: Ternary eccentricity

From:             symphonymous at hotmail dot com
Operating system: Ubuntu
PHP version:      5.6.14RC1
Package:          PHP Language Specification
Bug Type:         Bug
Bug description:Ternary eccentricity

Description:
------------
I suspect this is a bug as the behaviour is a little worrying.

I was using the following in a Laravel program

    $fieldLabel = // has a field label been manually defined
      ($fieldLabel =  $this->hasAttribute($fieldValue, 'FieldLabel'))
      ? $fieldLabel
      : ($this->parseFieldType($fieldValue) != 'hidden')         
        ? ucfirst($fieldKey)
        : '';

However when $label was defined it was resolving to 
$fieldLabel = ucfirst($fieldKey); 

(ie. the second ternary).

the resolution was to parenthesise the second ternary (which I should
have done in the first place):

    $fieldLabel = // has a field label been manually defined
      ($fieldLabel =  $this->hasAttribute($fieldValue, 'FieldLabel'))
      ? $fieldLabel
      : (($this->parseFieldType($fieldValue) != 'hidden')         
        ? ucfirst($fieldKey)
        : '');

The bug, in my eyes, is that aforementioned code should have thrown an
exception as the ternary statement gave an ambiguous result.

best

Jon

Test script:
---------------
// here is the same issue again in a simpler form, tested with 
// "php artisan tinker"

$foo = 1;

$bar = ($bar = $foo) ? $bar : ($bar = 2) ? 2 : 'null';

Expected result:
----------------
either an exception as the statement is ambiguous or 1;

I would suggest the former.

Actual result:
--------------
2

-- 
Edit bug report at https://bugs.php.net/bug.php?id=70618&edit=1
-- 
Try a snapshot (PHP 5.4):   https://bugs.php.net/fix.php?id=70618&r=trysnapshot54
Try a snapshot (PHP 5.5):   https://bugs.php.net/fix.php?id=70618&r=trysnapshot55
Try a snapshot (trunk):     https://bugs.php.net/fix.php?id=70618&r=trysnapshottrunk
Fixed in SVN:               https://bugs.php.net/fix.php?id=70618&r=fixed
Fixed in release:           https://bugs.php.net/fix.php?id=70618&r=alreadyfixed
Need backtrace:             https://bugs.php.net/fix.php?id=70618&r=needtrace
Need Reproduce Script:      https://bugs.php.net/fix.php?id=70618&r=needscript
Try newer version:          https://bugs.php.net/fix.php?id=70618&r=oldversion
Not developer issue:        https://bugs.php.net/fix.php?id=70618&r=support
Expected behavior:          https://bugs.php.net/fix.php?id=70618&r=notwrong
Not enough info:            https://bugs.php.net/fix.php?id=70618&r=notenoughinfo
Submitted twice:            https://bugs.php.net/fix.php?id=70618&r=submittedtwice
register_globals:           https://bugs.php.net/fix.php?id=70618&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=70618&r=php4
Daylight Savings:           https://bugs.php.net/fix.php?id=70618&r=dst
IIS Stability:              https://bugs.php.net/fix.php?id=70618&r=isapi
Install GNU Sed:            https://bugs.php.net/fix.php?id=70618&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=70618&r=float
No Zend Extensions:         https://bugs.php.net/fix.php?id=70618&r=nozend
MySQL Configuration Error:  https://bugs.php.net/fix.php?id=70618&r=mysqlcfg