Source Code for Module pyrobase.testing

 1  # -*- coding: utf-8 -*- 
 2  """ Unittest Helpers. 
 3   
 4      Copyright (c) 2009, 2011 The PyroScope Project <pyroscope.project@gmail.com> 
 5  """ 
 6  # This program is free software; you can redistribute it and/or modify 
 7  # it under the terms of the GNU General Public License as published by 
 8  # the Free Software Foundation; either version 2 of the License, or 
 9  # (at your option) any later version. 
10  # 
11  # This program is distributed in the hope that it will be useful, 
12  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
13  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
14  # GNU General Public License for more details. 
15  # 
16  # You should have received a copy of the GNU General Public License along 
17  # with this program; if not, write to the Free Software Foundation, Inc., 
18  # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 
19  import errno 
20  import StringIO 
21  from contextlib import contextmanager 
22   
23   
24 -class DictItemIO(StringIO.StringIO): 
25      """ StringIO that replaces itself in a dict on close. 
26      """ 
27   
28 -    def __init__(self, namespace, key, buf=''): 
29          self.namespace = namespace 
30          self.key = key 
31   
32          self.namespace[self.key] = self 
33          StringIO.StringIO.__init__(self, buf) 
34   
35   
36 -    def close(self): 
37          self.namespace[self.key] = self.getvalue() 
38          StringIO.StringIO.close(self) 
39   
40   
41  @contextmanager 
42 -def mockedopen(fakefiles=None): 
43      """ Mock the open call to use a dict as the file system. 
44   
45          @param fakefiles: Prepopulated filesystem, this is passed on as the context's target. 
46      """ 
47      import __builtin__ # pylint: disable=W0404 
48      fakefiles = fakefiles or {} 
49   
50      def mock_open(name, mode=None, buffering=None): # pylint: disable=W0613 
51          "Helper" 
52          mode = mode or "r" 
53          if mode.startswith('r'): 
54              if name not in fakefiles: 
55                  raise OSError((errno.ENOENT, "File not found", name)) 
56              try: 
57                  fakefiles[name].close() 
58              except AttributeError: 
59                  pass 
60              return StringIO.StringIO(fakefiles[name]) 
61          else: 
62              return DictItemIO(fakefiles, name) 
63   
64      builtin_open = __builtin__.open 
65      try: 
66          __builtin__.open = mock_open 
67          yield fakefiles 
68      finally: 
69          __builtin__.open = builtin_open 
70