chrome/common/extensions/docs/server2/future_test.py

   1 #!/usr/bin/env python
   2 # Copyright 2013 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 import traceback
   7 import unittest
   8
   9 from future import Future
  10
  11 class FutureTest(unittest.TestCase):
  12   def testNoValueOrDelegate(self):
  13     self.assertRaises(ValueError, Future)
  14
  15   def testValue(self):
  16     future = Future(value=42)
  17     self.assertEqual(42, future.Get())
  18     self.assertEqual(42, future.Get())
  19
  20   def testDelegateValue(self):
  21     assertFalse = self.assertFalse
  22     class delegate(object):
  23       def __init__(self):
  24         self._get_called = False
  25       def Get(self):
  26         assertFalse(self._get_called)
  27         self._get_called = True
  28         return 42
  29
  30     future = Future(delegate=delegate())
  31     self.assertEqual(42, future.Get())
  32     self.assertEqual(42, future.Get())
  33
  34   def testErrorThrowingDelegate(self):
  35     class FunkyException(Exception):
  36       pass
  37
  38     # Set up a chain of functions to test the stack trace.
  39     def qux():
  40       raise FunkyException()
  41     def baz():
  42       return qux()
  43     def bar():
  44       return baz()
  45     def foo():
  46       return bar()
  47     chain = [foo, bar, baz, qux]
  48
  49     assertFalse = self.assertFalse
  50     class delegate(object):
  51       def __init__(self):
  52         self._get_called = False
  53       def Get(self):
  54         assertFalse(self._get_called)
  55         self._get_called = True
  56         return foo()
  57
  58     fail = self.fail
  59     assertTrue = self.assertTrue
  60     def assert_raises_full_stack(future, err):
  61       try:
  62         future.Get()
  63         fail('Did not raise %s' % err)
  64       except Exception as e:
  65         assertTrue(isinstance(e, err))
  66         stack = traceback.format_exc()
  67         assertTrue(all(stack.find(fn.__name__) != -1 for fn in chain))
  68
  69     future = Future(delegate=delegate())
  70     assert_raises_full_stack(future, FunkyException)
  71     assert_raises_full_stack(future, FunkyException)
  72
  73 if __name__ == '__main__':
  74   unittest.main()