Throw when making a duplicate attribute using rename

Author: nielsdos

ext/dom/element.c

@@ -1879,6 +1879,15 @@ PHP_METHOD(DOM_Element, rename)
 		goto cleanup;
 	}
 
+	/* Check for duplicate attributes. */
+	if (nodep->type == XML_ATTRIBUTE_NODE) {
+		xmlAttrPtr existing = xmlHasNsProp(nodep->parent, localname, namespace_uri && ZSTR_VAL(namespace_uri)[0] != '\0' ? BAD_CAST ZSTR_VAL(namespace_uri) : NULL);
+		if (existing != NULL && existing != (xmlAttrPtr) nodep) {
+			php_dom_throw_error_with_message(INVALID_MODIFICATION_ERR, "An attribute with the given name in the given namespace already exists", /* strict */ true);
+			goto cleanup;
+		}
+	}
+
 	php_libxml_invalidate_node_list_cache(intern->document);
 
 	php_dom_libxml_ns_mapper *ns_mapper = php_dom_get_ns_mapper(intern);

ext/dom/tests/modern/extensions/attribute_renaming_conflict.phpt

@@ -0,0 +1,75 @@
+--TEST--
+Renaming an attribute node to a name that already exists
+--EXTENSIONS--
+dom
+--FILE--
+<?php
+
+$dom = DOM\XMLDocument::createFromString(<<<XML
+<!DOCTYPE root [
+    <!ELEMENT implied-attribute ANY>
+    <!ATTLIST implied-attribute hello CDATA #FIXED "world">
+]>
+<root a="b" c="d" xmlns:ns1="urn:a" ns1:foo="bar">
+    <implied-attribute my-attr="x"/>
+    <implied-attribute my-attr="x"/>
+</root>
+XML, LIBXML_DTDATTR);
+
+$root = $dom->documentElement;
+try {
+    $root->attributes[0]->rename(NULL, 'c');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->attributes[0]->rename(NULL, 'c');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->attributes[1]->rename(NULL, 'a');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->attributes[1]->rename('urn:a', 'foo');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->attributes[3]->rename('', 'a');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->firstElementChild->attributes[0]->rename(NULL, 'hello');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+try {
+    $root->firstElementChild->attributes[1]->rename(NULL, 'my-attr');
+} catch (DOMException $e) {
+    echo $e->getMessage(), "\n";
+}
+
+// This is here to validate that nothing actually changed
+echo $dom->saveXML();
+
+?>
+--EXPECT--
+An attribute with the given name in the given namespace already exists
+An attribute with the given name in the given namespace already exists
+An attribute with the given name in the given namespace already exists
+An attribute with the given name in the given namespace already exists
+An attribute with the given name in the given namespace already exists
+An attribute with the given name in the given namespace already exists
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE root [
+<!ELEMENT implied-attribute ANY>
+<!ATTLIST implied-attribute hello CDATA #FIXED "world">
+]>
+<root xmlns:ns1="urn:a" a="b" c="d" ns1:foo="bar">
+    <implied-attribute my-attr="x" hello="world"/>
+    <implied-attribute my-attr="x" hello="world"/>
+</root>

ext/dom/tests/modern/extensions/node_renaming_errors.phpt renamed to ext/dom/tests/modern/extensions/node_renaming_validation_erors.phpt

@@ -1,5 +1,5 @@
 --TEST--
-Node renaming errors
+Node renaming validation errors
 --EXTENSIONS--
 dom
 --FILE--