search_ancestor now uses *node_types as a parameter instead of a mix of tuple and simple string like isinstance.

jedi/parser/python/tree.py

@@ -1013,7 +1013,7 @@ class Param(PythonBaseNode):
         """
         Returns the function/lambda of a parameter.
         """
-        return search_ancestor(self, ('funcdef', 'lambdef'))
+        return search_ancestor(self, 'funcdef', 'lambdef')
 
     def get_code(self, normalized=False, include_prefix=True, include_comma=True):
         """

jedi/parser/tree.py

@@ -2,21 +2,18 @@ from abc import abstractmethod, abstractproperty
 from jedi._compatibility import utf8_repr, encoding, is_py3
 
 
-def search_ancestor(node, node_type_or_types):
+def search_ancestor(node, *node_types):
     """
     Recursively looks at the parents of a node and checks if the type names
     match.
 
     :param node: The node that is looked at.
-    :param node_type_or_types: A tuple or a string of type names that are
+    :param node_types: A tuple or a string of type names that are
         searched for.
     """
-    if not isinstance(node_type_or_types, (list, tuple)):
-        node_type_or_types = (node_type_or_types,)
-
     while True:
         node = node.parent
-        if node is None or node.type in node_type_or_types:
+        if node is None or node.type in node_types:
             return node