[ADD] tools: add some xml utilities

-create_xml_node()
-create_xml_nod_chain()

odoo/tools/xml_utils.py

@@ -14,3 +14,29 @@ def check_with_xsd(tree_or_str, xsd_path):
         #import UserError only here to avoid circular import statements with tools.func being imported in exceptions.py
         from odoo.exceptions import UserError
         raise UserError('\n'.join(str(e) for e in xml_errors.error_log))
+
+def create_xml_node_chain(first_parent_node, nodes_list, last_node_value=None):
+    """ Utility function for generating XML files nodes. Generates as a hierarchical
+    chain of nodes (each new node being the son of the previous one) based on the tags
+    contained in `nodes_list`, under the given node `first_parent_node`.
+    It will also set the value of the last of these nodes to `last_node_value` if it is
+    specified. This function returns the list of created nodes.
+    """
+    res = []
+    current_node = first_parent_node
+    for tag in nodes_list:
+        current_node = etree.SubElement(current_node, tag)
+        res.append(current_node)
+
+    if last_node_value is not None:
+        current_node.text = last_node_value
+    return res
+
+def create_xml_node(parent_node, node_name, node_value=None):
+    """ Utility function for managing XML. It creates a new node with the specified
+    `node_name` as a child of given `parent_node` and assigns it `node_value` as value.
+    :param parent_node: valid etree Element
+    :param node_name: string
+    :param node_value: string
+    """
+    return create_xml_node_chain(parent_node, [node_name], node_value)[0]