Removing the mutation in the factories for getting dep repositories

appengine/findit/crash/loglinear/changelist_classifier.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.
 
 import logging
 import math
 
 from common.chrome_dependency_fetcher import ChromeDependencyFetcher
 from crash import changelist_classifier
 from crash.loglinear.changelist_features import min_distance
 from crash.loglinear.changelist_features import top_frame_index
 from crash.loglinear.model import ToFeatureFunction
 from crash.loglinear.model import UnnormalizedLogLinearModel
 from crash.stacktrace import CallStack
 from crash.stacktrace import Stacktrace
 
 
 class LogLinearChangelistClassifier(object):
   """A ``LogLinearModel``-based implementation of CL classification."""
 
-  def __init__(self, repository, get_repository, weights, top_n_frames=7,
-               top_n_suspects=3):
+  def __init__(self, get_repository, weights, top_n_frames=7, top_n_suspects=3):
     """Args:
-      repository (Repository): the Git repository for getting CLs to classify.
       get_repository (callable): a function from DEP urls to ``Repository``
         objects, so we can get changelogs and blame for each dep. Notably,
         to keep the code here generic, we make no assumptions about
         which subclass of ``Repository`` this function returns. Thus,
         it is up to the caller to decide what class to return and handle
         any other arguments that class may require (e.g., an http client
         for ``GitilesRepository``).
       weights (dict of float): the weights for the features. The keys of
         the dictionary are the names of the feature that weight is
         for. We take this argument as a dict rather than as a list so that
         callers needn't worry about what order to provide the weights in.
       top_n_frames (int): how many frames of each callstack to look at.
       top_n_suspects (int): maximum number of suspects to return.
     """
-    self._repository = repository
-    self._dependency_fetcher = ChromeDependencyFetcher(self._repository)
+    self._dependency_fetcher = ChromeDependencyFetcher(get_repository)
     self._get_repository = get_repository
     self._top_n_frames = top_n_frames
     self._top_n_suspects = top_n_suspects
 
     feature_function = ToFeatureFunction([
         top_frame_index.TopFrameIndexFeature(top_n_frames),
         min_distance.MinDistanceFeature(),
     ])
 
     weight_list = [
@@ skipping 75 matching lines @@
     regression_deps_rolls = {}
     for dep_path, dep_roll in dep_rolls.iteritems():
       if not dep_roll.old_revision or not dep_roll.new_revision:
         logging.info('Skip %s denpendency %s',
                      'added' if dep_roll.new_revision else 'deleted', dep_path)
         continue
       regression_deps_rolls[dep_path] = dep_roll
 
     dep_to_file_to_changelogs, ignore_cls = (
         changelist_classifier.GetChangeLogsForFilesGroupedByDeps(
-            regression_deps_rolls, stack_deps, self._repository))
+            regression_deps_rolls, stack_deps, self._get_repository))
     dep_to_file_to_stack_infos = (
         changelist_classifier.GetStackInfosForFilesGroupedByDeps(
             report.stacktrace, stack_deps))
 
     # Get the possible suspects.
     suspects = changelist_classifier.FindSuspects(
         dep_to_file_to_changelogs,
         dep_to_file_to_stack_infos,
         stack_deps,
         self._get_repository,
@@ skipping 83 matching lines @@
           all_changed_files[changed_file.name] = changed_file
           continue
 
         assert accumulated_changed_file.blame_url == changed_file.blame_url, (
             ValueError('Blame URLs do not match: %s != %s'
                 % (accumulated_changed_file.blame_url, changed_file.blame_url)))
         accumulated_changed_file.reasons.extend(changed_file.reasons or [])
 
     return sorted(all_changed_files.values(),
         key=lambda changed_file: changed_file.name)