Removing the mutation in the factories for getting dep repositories

appengine/findit/crash/crash_pipeline.py

Index: appengine/findit/crash/crash_pipeline.py
diff --git a/appengine/findit/crash/crash_pipeline.py b/appengine/findit/crash/crash_pipeline.py
index a554223750dbaccbf9785296790a69eae49b4b2e..e12eaca7fb75c353caf86740368a9b1a1895e853 100644
--- a/appengine/findit/crash/crash_pipeline.py
+++ b/appengine/findit/crash/crash_pipeline.py
@@ -22,7 +22,7 @@ from model import analysis_status
 
 
 # TODO(http://crbug.com/659346): write complete coverage tests for this.
-def FinditForClientID(client_id, repository): # pragma: no cover
+def FinditForClientID(client_id, get_repository): # pragma: no cover
   """Construct a Findit object from a client id string specifying the class.
 
   We cannot pass Findit objects to the various methods in
@@ -52,7 +52,7 @@ def FinditForClientID(client_id, repository): # pragma: no cover
     raise ValueError('FinditForClientID: '
         'unknown or unsupported client %s' % client_id)
 
-  return cls(repository)
+  return cls(get_repository)
 
 
 # Some notes about the classes below, for people who are not familiar
@@ -87,14 +87,16 @@ def FinditForClientID(client_id, repository): # pragma: no cover
 # twice. This also means ``run`` can't store anything in the pipeline
 # object and expect it to still be available in the ``finalized`` method.
 
+def _CachedGitilesRepositoryFactory(repo_url): # pragma: no cover

[Sharu Jiang, 2016/12/28 23:05:12]

what's the reason for ``pragma: no cover`` here?

[wrengr, 2016/12/29 20:57:31]

Apparently it's never called by the unit tests ¯\_(ツ)_/¯

+  return cached_gitiles_repository.CachedGitilesRepository(
+      HttpClientAppengine(), repo_url)
+
+
 class CrashBasePipeline(BasePipeline):
   def __init__(self, client_id, crash_identifiers):
     super(CrashBasePipeline, self).__init__(client_id, crash_identifiers)
     self._crash_identifiers = crash_identifiers
-    self._findit = FinditForClientID(
-        client_id,
-        cached_gitiles_repository.CachedGitilesRepository(
-            HttpClientAppengine()))
+    self._findit = FinditForClientID(client_id, _CachedGitilesRepositoryFactory)
 
   @property
   def client_id(self): # pragma: no cover