Setting DOMAttr::textContent results in an empty attribute value.

[ThomasWeinert]

Description

The following code:

<?php
$document = new DOMDocument();
$document->loadXML('<element attribute="value"/>');
$attribute = $document->documentElement->getAttributeNode('attribute');

// output loaded attribute value
var_dump($attribute->textContent);

// change value
$attribute->textContent = 'new value';

// output changed value
var_dump($attribute->textContent);

Resulted in this output:

string(5) "value"
string(0) ""

But I expected this output instead:

string(5) "value"
string(9) "new value"

https://3v4l.org/ouRV0

This work in PHP Versions 5.6.1 to 5.6.13, it is broken for any PHP version after that.

PHP Version

PHP 8.2.1

Operating System

No response

[cmb69]

Almost certainly caused by b2954c6.

[nielsdos]

The following patch works for me. Although I'm not 100% sure this is the right way. I just mimicked the libxml2 source code to get the "else if" condition (https://github.com/GNOME/libxml2/blob/master/tree.c#L5927). EDIT: I'm missing the properties update I think so the "else if" case is not 100% correct yet. I guess the "else if" case can be solved by calling the xmlNodeSetContent function.

diff --git a/ext/dom/node.c b/ext/dom/node.c
index d55ac99efe..78023389a9 100644
--- a/ext/dom/node.c
+++ b/ext/dom/node.c
@@ -769,17 +769,23 @@ int dom_node_text_content_write(dom_object *obj, zval *newval)
 		return FAILURE;
 	}
 
-	if (nodep->type == XML_ELEMENT_NODE || nodep->type == XML_ATTRIBUTE_NODE) {
+	const xmlChar *xmlChars = (const xmlChar *) ZSTR_VAL(str);
+	int type = nodep->type;
+
+	if (type == XML_ELEMENT_NODE || type == XML_ATTRIBUTE_NODE) {
 		if (nodep->children) {
 			node_list_unlink(nodep->children);
 			php_libxml_node_free_list((xmlNodePtr) nodep->children);
 			nodep->children = NULL;
 		}
+
+		xmlNode *textNode = xmlNewText(xmlChars);
+		xmlAddChild(nodep, textNode);
+	} else if (type == XML_TEXT_NODE || type == XML_CDATA_SECTION_NODE || type == XML_ENTITY_REF_NODE || type == XML_ENTITY_NODE || type == XML_PI_NODE || type == XML_COMMENT_NODE || type == XML_NOTATION_NODE) {
+		xmlFree(nodep->content);
+		nodep->content = xmlStrdup(xmlChars);
 	}
 
-	/* we have to use xmlNodeAddContent() to get the same behavior as with xmlNewText() */
-	xmlNodeSetContent(nodep, (xmlChar *) "");
-	xmlNodeAddContent(nodep, (xmlChar *) ZSTR_VAL(str));
 	zend_string_release_ex(str, 0);
 
 	return SUCCESS;