Converting various classes to namedtuples

appengine/findit/crash/results.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from collections import namedtuple
 
 # TODO(http://crbug.com/644476): this class needs a better name.
 class AnalysisInfo(namedtuple('AnalysisInfo',
     ['min_distance', 'min_distance_frame'])):
   __slots__ = ()
 
 
+# TODO(wrengr): it's not clear why the ``priority`` is stored at all,
+# given that every use in this file discards it. ``Result.file_to_stack_infos``
+# should just store pointers directly to the frames themselves rather
+# than needing this intermediate object.
+# TODO(http://crbug.com/644476): this class needs a better name.
+class StackInfo(namedtuple('StackInfo', ['frame', 'priority'])):
+  """Pair of a frame and the ``priority`` of the ``CallStack`` it came from."""
+  __slots__ = ()
+
+
 # TODO(http://crbug.com/644476): this class needs a better name.
-# TODO(http://crbug.com/661822): convert this into a namedtuple.
 class Result(object):
   """Represents findit culprit result."""
 
   def __init__(self, changelog, dep_path,
                confidence=None, reasons=None, changed_files=None):
     self.changelog = changelog
     self.dep_path = dep_path
     self.confidence = confidence
     self.reasons = reasons
     self.changed_files = changed_files
 
     # TODO(wrengr): (a) make these two fields private/readonly
     # TODO(wrengr): (b) zip them together.
-    # TODO(http://crbug.com/661822): change stack_info pair to a namedtuple.
     self.file_to_stack_infos = {}
     self.file_to_analysis_info = {}
 
   def ToDict(self):
     return {
         'url': self.changelog.commit_url,
         'review_url': self.changelog.code_review_url,
         'revision': self.changelog.revision,
         'project_path': self.dep_path,
         'author': self.changelog.author_email,
@@ skipping 37 matching lines @@
     When a file_path is found both shown in stacktrace and touched by
     the revision of this result, update result with the information of
     this file.
 
     Inserts the file path and its stack infos, and updates the min distance
     if less distance is found between touched lines of this result and
     crashed lines in the file path.
 
     Args:
       file_path (str): File path of the crashed file.
-      stack_infos (list): List of (frame, stack_priority), represents frames of
-        this file and the callstack priorities of those frames.
+      stack_infos (list of StackInfo): List of the frames of this file
+        together with their callstack priorities.
       blame (Blame): Blame oject of this file.
     """
     self.file_to_stack_infos[file_path] = stack_infos
 
     if not blame:
       return
 
     min_distance = float('inf')
     min_distance_frame = stack_infos[0][0]
     for region in blame:
@@ skipping 63 matching lines @@
     """
     for changelog in changelogs:
       if self._ignore_cls and changelog.revision in self._ignore_cls:
         continue
 
       if changelog.revision not in self:
         self[changelog.revision] = MatchResult(changelog, dep_path)
 
       match_result = self[changelog.revision]
       match_result.Update(file_path, stack_infos, blame)