Currently, an empty check like the following returns false because
SimpleXML only checks for node existence in has_property. I'd like to
propose the attached patch to change this to look at the node's children
and apply PHP's emptiness rules to the content.

$data = '<?xml version="1.0 ?>
<doc>
<e1></e1>
<e2>0</e2>
<f1>foo</f1>
<x eprop="" fprop="data" />
</doc>';

$s = simplexml_load_string($data);
var_dump(empty($s->e1)); // Currently false
var_dump(empty($s->e2)); // Currently false
var_dump(empty($s->f1)); // False
var_dump(empty($s->x['eprop'])); // Currently false
var_dump(empty($s->x['fprop'])); // False

Note that this patch only effects elements which only contains an empty
text node or only a text node with a literal "0". If the element
contains real children, then it's considered to be non-empty (even if
those children are in turn empty themselves).

-Sara

Index: ext/simplexml/simplexml.c

RCS file: /repository/php-src/ext/simplexml/simplexml.c,v
retrieving revision 1.151.2.23
diff -u -p -r1.151.2.23 simplexml.c
--- ext/simplexml/simplexml.c 1 Jan 2007 09:40:27 -0000 1.151.2.23
+++ ext/simplexml/simplexml.c 2 Jul 2007 20:30:05 -0000
@@ -692,6 +692,11 @@ static int sxe_prop_dim_exists(zval *obj
attr = attr->next;
}
}

•                   if (exists && check_empty == 1 &&
  

•                           (!attr->children || !attr->children->content || !attr->children->content[0] || !xmlStrcmp(attr->children->content, "0")) ) {
  

•                           /* Attribute with no content in it's text node */
  

•                           exists = 0;
  

•                   }
            }
  
            if (elements) {
  

@@ -714,6 +719,11 @@ static int sxe_prop_dim_exists(zval *obj
}
if (node) {
exists = 1;

•                            if (check_empty == 1 &&
  

•                                   (!node->children || (node->children->type == `XML_TEXT_NODE` && !node->children->next &&
  

•                                           (!node->children->content || !node->children->content[0] || !xmlStrcmp(node->children->content, "0")))) ) {
  

•                                   exists = 0;
  

•                           }
                    }
            }
    }
  

--

Tested it and makes perfect sense.

--
David Coallier,
Founder & Software Architect,
Agora Production (http://agoraproduction.com)
51.42.06.70.18