Do not set optional xml.Node attrs to empty string

Author: mzagozen

base/src/xml.ext.c

@@ -69,13 +69,14 @@ static unsigned char* copy_with_xml_escape(unsigned char *dst, B_str src, int es
 }
 
 // Helper function to collect text from consecutive TEXT and CDATA nodes
-// Returns the combined string and updates the node pointer to the first non-text node
+// Returns the combined string (or NULL if there is no text/CDATA content) and
+// updates the node pointer to the first non-text node
 // Note: cur_ptr is passed by reference (pointer to pointer) so we can update the caller's pointer
 //       to skip past all consumed text/CDATA nodes
 static B_str collect_text_cdata_nodes(xmlNodePtr *cur_ptr) {
     xmlNodePtr cur = *cur_ptr;
     if (!cur || (cur->type != XML_TEXT_NODE && cur->type != XML_CDATA_SECTION_NODE)) {
-        return to$str("");
+        return NULL;
     }
 
     // Count total length of combined text and CDATA nodes
@@ -106,7 +107,7 @@ static B_str collect_text_cdata_nodes(xmlNodePtr *cur_ptr) {
     }
 
     *cur_ptr = cur;
-    return to$str("");
+    return NULL;
 }
 
 xmlQ_Node $NodePtr2Node(xmlNodePtr node) {

test/stdlib_tests/src/test_xml.act

@@ -182,4 +182,4 @@ def _test_xml_namespace_attributes_undefined():
 def _test_xml_repr():
     test_xml = """<data xmlns="http://default"><a xmlns:ns="http://foo" ns:operation="remove"><ns:b ns:type="element">text</ns:b></a></data>"""
     d = xml.decode(test_xml)
-    testing.assertEqual(repr(d), "xml.Node('data', nsdefs=[(None, 'http://default')], children=[xml.Node('a', nsdefs=[('ns', 'http://foo')], attributes=[('ns:operation', 'remove')], children=[xml.Node('b', prefix='ns', attributes=[('ns:type', 'element')], text='text')])])")
+    testing.assertEqual(repr(d), "xml.Node(tag='data', nsdefs=[(None, 'http://default')], children=[xml.Node(tag='a', nsdefs=[('ns', 'http://foo')], attributes=[('ns:operation', 'remove')], children=[xml.Node(tag='b', prefix='ns', attributes=[('ns:type', 'element')], text='text')])])")