commit 8397c43c30e24d12dc01a84f1b2fc51999506f8b Author: Damian Johnson <atagar@torproject.org> Date: Thu Feb 2 10:58:21 2017 -0800 Avoid parsing malformed lines multiple times Descriptor lines usually set multiple attributes. When we've read a line for one of those attributes there's no point in reading it again for another. This has no noticeable impact I can tell on performance (multiple calls to a variety of related attributes in a malformed descriptor is very much an edge case). Just doing this because when it happens it's clearly wasted work. --- stem/descriptor/__init__.py | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/stem/descriptor/__init__.py b/stem/descriptor/__init__.py index 8c31b86..7c64293 100644 --- a/stem/descriptor/__init__.py +++ b/stem/descriptor/__init__.py @@ -646,9 +646,9 @@ class Descriptor(object): # Doing so works since it stops recursing after several dozen iterations # (not sure why), but horrible in terms of performance. - def has_attr(): + def has_attr(attr): try: - super(Descriptor, self).__getattribute__(name) + super(Descriptor, self).__getattribute__(attr) return True except: return False @@ -658,18 +658,20 @@ class Descriptor(object): # a. we still need to lazy load this # b. we read the whole descriptor but it wasn't present, so needs the default - if name in self.ATTRIBUTES and not has_attr(): + if name in self.ATTRIBUTES and not has_attr(name): default, parsing_function = self.ATTRIBUTES[name] if self._lazy_loading: try: parsing_function(self, self._entries) except (ValueError, KeyError): - # Despite having a validation failure we might've set something. If - # not then set the default. + # Set defaults for anything the parsing function should've covered. + # Despite having a validation failure some attributes might be set in + # which case we keep them. - if not has_attr(): - setattr(self, name, _copy(default)) + for attr_name, (attr_default, attr_parser) in self.ATTRIBUTES.items(): + if parsing_function == attr_parser and not has_attr(attr_name): + setattr(self, attr_name, _copy(attr_default)) else: setattr(self, name, _copy(default))