# HG changeset patch
# User paulb
# Date 1138148808 0
# Node ID 129565ae4d6a1ea8472861ae36e3569de15e9e2d
# Parent  761ef670c5a937c87c8069b669cf5d4e2d620bea
[project @ 2006-01-25 00:26:48 by paulb]
Changed selector initialisation to discard references which are no longer
valid. This helps in cases where selectors are reinitialised in the context
of a new document.

diff -r 761ef670c5a9 -r 129565ae4d6a XSLForms/Fields.py
--- a/XSLForms/Fields.py	Fri Jan 20 17:37:33 2006 +0000
+++ b/XSLForms/Fields.py	Wed Jan 25 00:26:48 2006 +0000
@@ -213,18 +213,16 @@
                     if index < 0:
                         break
 
-                    # NOTE: Controversial creation of potentially non-existent
-                    # NOTE: nodes.
+                    # Where a node cannot be found, do not create a selector.
 
-                    try:
-                        node = self._enter_element(node, name, index)
-                    except FieldsError, exc:
-                        raise FieldsError, "In field '%s', name '%s' and index '%s' could not be added, since '%s' was found." % (
-                            field, name, index, exc.args[0])
+                    node = self._find_element(node, name, index)
+                    if node is None:
+                        break
 
             if not selectors.has_key(selector_name):
                 selectors[selector_name] = []
-            selectors[selector_name].append(node)
+            if node is not None:
+                selectors[selector_name].append(node)
 
     def _append_element(self, node, name):
 
@@ -259,6 +257,23 @@
 
         return new_node
 
+    def _find_element(self, node, name, index):
+
+        """
+        From 'node' find the element with the given 'name' at the
+        given 'index' position amongst the child elements. Return
+        None if no such element exists.
+        """
+
+        elements = node.xpath("*")
+        try:
+            new_node = elements[index]
+            if new_node.localName != name:
+                return None
+        except IndexError:
+            return None
+        return new_node
+
     def _get_model_name_and_components(self, field):
 
         """
@@ -433,6 +448,7 @@
     items = [
             ("_action_update", "Some value"),
             ("_action_delete=/zoo$1/cage$2", "Some value"),
+            ("_action_nasty=/zoo$1/cage$3", "Some value"),
             ("/actions$1/update$1/selected", "Some value"), # Not actually used in output documents or input.
             ("/zoo$1/name", "The Zoo זרו"),
             ("/zoo$1/cage$1/name", "reptiles"),