Edit report at https://bugs.php.net/bug.php?id=50892&edit=1
ID: 50892
Comment by: arth dot inbox at gmail dot com
Reported by: EdwardDrapkin at gmail dot com
Summary: Protected members of non-congruent children classes
are visible
Status: Open
Type: Feature/Change Request
Package: Class/Object related
Operating System: Irrelevant
PHP Version: 5.3.1
Block user comment: N
Private report: N
New Comment:
normandiggs, your sample is irrelevant.
It's ok to access private and protected properties from same type object.
It's bad to access protected properties from different type object.
Why I hate this behavior:
http://3v4l.org/tiOC5 - we receive protected value
http://3v4l.org/uT9PC - we receive fatal error
We should not to rely to implementation of B class (see fiddles)
Another note - this behavior was broken in 5.2 version.
Previous Comments:
------------------------------------------------------------------------
[2011-02-16 12:17:42] normandiggs at gmail dot com
Another one example, even without "extends":
class Page_Element
{
protected $name = 'name*';
public function __construct(Page_Element $child = null)
{
echo $this->name;
echo $child->name;
}
}
new Page_Element(new Page_Element(null));
(from http://youtrack.jetbrains.net/issue/WI-4663)
So why $child->name can be accessed? It's new object!
------------------------------------------------------------------------
[2010-05-06 21:58:21] php at b8r dot org
Our problem differs slightly from this issue, but I think they share a root cause. Here's a
sample of code with the expected outcome.
abstract class A {
/**
* undocumented function
*
* @return void
*/
public function __get($propertyName)
{
$val = $this->$propertyName;
echo "Current Value of '{$propertyName}' is '{$val}'\n";
return $val;
}
public function __set($propertyName, $propertyValue)
{
echo "Setting Property '{$propertyName}' to
'{$propertyValue}'\n";
$this->$propertyName = $propertyValue;
}
}
class B extends A {
protected $name;
public function populateName($val) {
$a = 'name';
$this->$a = $val;
}
public function testit() {
$b = new B();
$b->name = 'internal';
$b->name;
}
}
$two = new B();
$two->name = 'external';
$two->name;
$two->testit();
Expected Results:
-----------------
Setting Property 'name' to 'external'
Current Value of 'name' is 'external'
Setting Property 'name' to 'internal'
Current Value of 'name' is 'internal'
Actual Results:
----------------
Setting Property 'name' to 'external'
Current Value of 'name' is 'external'
------------------------------------------------------------------------
[2010-05-06 21:39:30] php at b8r dot org
It causes more problems then the original poster notes. We've run into problems using __get
and __set. Since php see's the member as "in scope" for both classes, the __get and
__set methods don't get called.
------------------------------------------------------------------------
[2010-02-02 03:28:51] colder@php.net
At a second glance, it really looks like it is wrong.
The visibility check should also be based on the object from which the
properties are read.
As for my "it works that way in Java" argument, it contradicts the java
specifications:
http://java.sun.com/docs/books/jls/third_edition/html/names.html#6.6.2.1
and hence is invalid. (Thanks oorza for pointing that out)
There is no design ground to accept that, it is a bug. The question that
remains is: is it worth to fix BC-wise?
------------------------------------------------------------------------
[2010-02-01 14:23:51] johannes@php.net
That's a fundamental part of a class based inheritance system.Changing this won't only
affect BC but also the fundamental design.
------------------------------------------------------------------------
The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
https://bugs.php.net/bug.php?id=50892
--
Edit this bug report at https://bugs.php.net/bug.php?id=50892&edit=1