New rtc dump analyzing tool in Python

tools/py_event_log_analyzer/misc_test.py

+#!/usr/bin/env python
+#  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+#
+#  Use of this source code is governed by a BSD-style license
+#  that can be found in the LICENSE file in the root of the source
+#  tree. An additional intellectual property rights grant can be found
+#  in the file PATENTS.  All contributing project authors may
+#  be found in the AUTHORS file in the root of the source tree.
+
+"""Run the tests with
+
+      python misc_test.py
+or
+      python3 misc_test.py

[kwiberg-webrtc, 2016/06/09 12:27:20]

Question (because I'm too lazy to find it out myself): Are the unit tests
actually run with both Python 2 and 3? If not, the untested version will
inevitably rot after a while.

[phoglund, 2016/06/09 12:47:09]

It's python 2, and all scripts we have are in webrtc/chromium are written for
python 2. If you want coverage on python 3 that's probably easy to add.

+"""
+
+from __future__ import division
+import random
+import unittest
+
+import misc
+
+
+class TestMisc(unittest.TestCase):
+
+  def testUnwrapMod3(self):
+    data = [0, 1, 2, 0, -1, -2, -3, -4]
+    unwrapped_3 = misc.unwrap(data, 3)
+    self.assertEqual([0, 1, 2, 3, 2, 1, 0, -1], unwrapped_3)
+
+  def testUnwrapMod4(self):
+    data = [0, 1, 2, 0, -1, -2, -3, -4]
+    unwrapped_4 = misc.unwrap(data, 4)
+    self.assertEqual([0, 1, 2, 0, -1, -2, -3, -4], unwrapped_4)
+
+  def testDataShouldNotChangeAfterUnwrap(self):
+    data = [0, 1, 2, 0, -1, -2, -3, -4]
+    _ = misc.unwrap(data, 4)
+
+    self.assertEqual([0, 1, 2, 0, -1, -2, -3, -4], data)
+
+  def testRandomlyMultiplesOfModAdded(self):
+    # `unwrap` definition says only multiples of mod are added.
+    random_data = [random.randint(0, 9) for _ in range(100)]
+
+    for mod in range(1, 100):
+      random_data_unwrapped_mod = misc.unwrap(random_data, mod)
+
+      for (old_a, a) in zip(random_data, random_data_unwrapped_mod):
+        self.assertEqual((old_a - a) % mod, 0)
+
+  def testRandomlyAgainstInequalityDefinition(self):
+    # Data has to satisfy -mod/2 <= difference < mod/2 for every
+    # difference between consecutive values after unwrap.
+    random_data = [random.randint(0, 9) for _ in range(100)]
+
+    for mod in range(1, 100):
+      random_data_unwrapped_mod = misc.unwrap(random_data, mod)
+
+      for (a, b) in zip(random_data_unwrapped_mod,
+                        random_data_unwrapped_mod[1:]):
+        self.assertTrue(-mod / 2 <= b - a < mod / 2)
+
+  def testRandomlyDataShouldNotChangeAfterUnwrap(self):
+    random_data = [random.randint(0, 9) for _ in range(100)]
+    random_data_copy = random_data[:]
+    for mod in range(1, 100):
+      _ = misc.unwrap(random_data, mod)
+
+      self.assertEqual(random_data, random_data_copy)
+
+if __name__ == "__main__":
+  unittest.main()