Make repeated running of instrumentation tests faster.

build/android/pylib/apk_info.py

Index: build/android/pylib/apk_info.py
diff --git a/build/android/pylib/apk_info.py b/build/android/pylib/apk_info.py
index 6b0b7f63e68430d02eca6a264a4ea3b50717993f..7fb5a98094a17e35ae90da39935045677e7dd184 100644
--- a/build/android/pylib/apk_info.py
+++ b/build/android/pylib/apk_info.py
@@ -5,11 +5,15 @@
 """Gathers information about APKs."""
 
 import collections
+import logging
 import os
+import pickle
 import re
 
 import cmd_helper
 
+# If you change the cached output of proguard, increment this number
+PICKLE_FORMAT_VERSION = 1
 
 def GetPackageNameForApk(apk_path):
   """Returns the package name of the apk file."""
@@ -50,6 +54,18 @@ class ApkInfo(object):
     self._Initialize()
 
   def _Initialize(self):
+    pickle_name = self._jar_path + "-proguard.pickle"

[frankf, 2012/11/22 03:03:48]

single quotes here and below.

[Yaron, 2012/11/26 18:26:15]

Done.

+    if os.path.exists(pickle_name) and (os.stat(pickle_name).st_mtime >
+                                        os.stat(self._jar_path).st_mtime):

[frankf, 2012/11/22 03:03:48]

os.path.getmtime() is slightly preferred.

[Yaron, 2012/11/26 18:26:15]

Done.

+      logging.info("Loading cached proguard output from %s", pickle_name)

[bulach, 2012/11/22 13:51:20]

see below, probably best as:
try:
  with open(pickle_name, 'r') as r:
    d = pickle.loads(r.read())
  if d['VERSION'] == PICKLE_FORMAT_VERSION:
    self._annotation_map = d['ANNOTATION_MAP']
    self._test_methods = d['TEST_METHODS']
    return
except:
  logging.warning('PICKLE_FORMAT_VERSION has changed, ignoring cache')

[Yaron, 2012/11/26 18:26:15]

Done.

+      unpickler = pickle.Unpickler(open(pickle_name))
+      if PICKLE_FORMAT_VERSION == unpickler.load():

[bulach, 2012/11/22 13:51:20]

prefer to pickle one dict, see below..

[Yaron, 2012/11/26 18:26:15]

Done.

+        self._annotation_map = unpickler.load()
+        self._test_methods = unpickler.load()
+        return
+      else:
+        logging.warning("PICKLE_FORMAT_VERSION has changed, ignoring cache")

[frankf, 2012/11/22 03:03:48]

Can you put this in a finally block with above lines in a try. We probably don't
want to propagate any exceptions as this in not critical. 

[Yaron, 2012/11/26 18:26:15]

Done.

+
     proguard_output = cmd_helper.GetCmdOutput([self._PROGUARD_PATH,
                                                '-injars', self._jar_path,
                                                '-dontshrink',
@@ -98,6 +114,12 @@ class ApkInfo(object):
                 annotation + ':' + value)
             has_value = False
 
+    logging.info("Storing proguard output to %s", pickle_name)
+    pickler = pickle.Pickler(open(pickle_name, 'w'))

[bulach, 2012/11/22 13:51:20]

pickle.dumps with a dict works better, no need for Pickler / keep the order
consistent between reader and writer..

so perhaps:
  d = {'VERSION': PICKLE_FORMAT_VERSION,
       'ANNOTATION_MAP': self._annotation_map,
       'TEST_METHODS': self._test_methods}
  with open(pickle_name, 'w') as f:
    f.write(pickle.dumps(d))

[Yaron, 2012/11/26 18:26:15]

Done.

+    pickler.dump(PICKLE_FORMAT_VERSION)
+    pickler.dump(self._annotation_map)
+    pickler.dump(self._test_methods)
+
   def _GetAnnotationMap(self):
     return self._annotation_map