PHP SimpleXML is broken: Part 1

[yatur]

The following code does not work as expected:

$xml = simplexml_load_string("text"); $node = $xml->xpath("/root/a")[0]; if ($node) process($node); // process($node) may not be called for some valid nodes

Unlike most other objects, SimpleXmlElement may evaluate as false even when it is not null. Specifically, SimpleXmlElements representing empty

Comments

[dennisgorelik]

> so whatever goes inside the “if” will be skipped for them.

What does "goes inside the “if”" mean?
In your example "$node" is inside of "if", right?

Do you mean that if XPath found empty element, then resulting $node would be null?

Or you mean that if input XML contains empty node, then XPath search result would always evaluate to null even if it found not empty node?

[yatur]

Everything that may be misunderstood will be misunderstood.
I fixed the example, so it is now (hopefully) clearer.

[dennisgorelik]

> Everything that may be misunderstood will be misunderstood.

Of course.

> I fixed the example

I do not see what you fixed.

If your xpath was "/root/a" instead of "/root/b" it would be more clear I guess.
But your current xpath example is searching for node that is not empty.

[yatur]

> I do not see what you fixed.

The 'goes inside if' part.

> But your current xpath example is searching for node that is not empty.

Well, that's the bug I found. The node is not empty, but PHP thinks it is. But I agree, it's confusing in this setting. Changed query to /root/a.

[dennisgorelik]

Ahh, so it is combination of two things:
1) Weird interpretation of "if(object)".
2) Xpath bug that sometimes treats non-empty nodes - as if they were empty.
Right?