Improved unit-test line coverage and quality.

In particular

- Upgraded some unit test modules to `unittest2`.
- Got to 100% line coverage in `test_jwt`, `test_clientsecrets`,
  and `test_service_account` by using `self.assertRaises`
  instead of `self.fail()`
- In some places used `self.assertRaises` as a context manager so
  the thrown exception can be inspected / compared against. This
  is done instead of manually catching the exception and
  holding on to it (`unittest2` backports this feature from
  `unittest` that was not available in Python 2.6)
- Added license to `test_multistore_file`
- Removed legacy `python2.4` hashbang from `test_jwt` and
  `test_service_account`
- Added `unittest2` as a test dependency in `tox.ini`
- Updated `test_clientsecrets.test_load_by_filename_missing_file`
  to use the `self.assertRaises` context manager (this was
  a problem in #349 and #350)
- Updated `test_jwt` module docstring to reflect actual purpose

1 files changed, 5 insertions, 13 deletions

diff --git a/tests/test_service_account.py b/tests/test_service_account.py
index 5cf1c1c..1ba0cae 100644
--- a/tests/test_service_account.py
+++ b/tests/test_service_account.py
@@ -1,5 +1,3 @@
-#!/usr/bin/python2.4
-#
 # Copyright 2014 Google Inc. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -61,17 +59,11 @@ class ServiceAccountCredentialsTests(unittest.TestCase):
 
         self.assertTrue(rsa.pkcs1.verify(b'Google', signature, pub_key))
 
-        try:
-            rsa.pkcs1.verify(b'Orest', signature, pub_key)
-            self.fail('Verification should have failed!')
-        except rsa.pkcs1.VerificationError:
-            pass  # Expected
-
-        try:
-            rsa.pkcs1.verify(b'Google', b'bad signature', pub_key)
-            self.fail('Verification should have failed!')
-        except rsa.pkcs1.VerificationError:
-            pass  # Expected
+        self.assertRaises(rsa.pkcs1.VerificationError,
+                          rsa.pkcs1.verify, b'Orest', signature, pub_key)
+        self.assertRaises(rsa.pkcs1.VerificationError,
+                          rsa.pkcs1.verify,
+                          b'Google', b'bad signature', pub_key)
 
     def test_service_account_email(self):
         self.assertEqual(self.service_account_email,