syspathcontext.py
69 lines
| 2.0 KiB
| text/x-python
|
PythonLexer
Brian Granger
|
r2252 | # encoding: utf-8 | ||
| """ | ||||
| Context managers for adding things to sys.path temporarily. | ||||
| Authors: | ||||
| * Brian Granger | ||||
| """ | ||||
| #----------------------------------------------------------------------------- | ||||
Matthias BUSSONNIER
|
r5390 | # Copyright (C) 2008-2011 The IPython Development Team | ||
|
Brian Granger
|
r2252 | # | ||
| # Distributed under the terms of the BSD License. The full license is in | ||||
| # the file COPYING, distributed as part of this software. | ||||
| #----------------------------------------------------------------------------- | ||||
| #----------------------------------------------------------------------------- | ||||
| # Imports | ||||
| #----------------------------------------------------------------------------- | ||||
| import sys | ||||
|
Brian Granger
|
r2498 | #----------------------------------------------------------------------------- | ||
| # Code | ||||
| #----------------------------------------------------------------------------- | ||||
|
Brian Granger
|
r2252 | class appended_to_syspath(object): | ||
| """A context for appending a directory to sys.path for a second.""" | ||||
| def __init__(self, dir): | ||||
| self.dir = dir | ||||
| def __enter__(self): | ||||
| if self.dir not in sys.path: | ||||
| sys.path.append(self.dir) | ||||
| self.added = True | ||||
| else: | ||||
| self.added = False | ||||
| def __exit__(self, type, value, traceback): | ||||
| if self.added: | ||||
| try: | ||||
| sys.path.remove(self.dir) | ||||
| except ValueError: | ||||
| pass | ||||
| # Returning False causes any exceptions to be re-raised. | ||||
| return False | ||||
| class prepended_to_syspath(object): | ||||
| """A context for prepending a directory to sys.path for a second.""" | ||||
| def __init__(self, dir): | ||||
| self.dir = dir | ||||
| def __enter__(self): | ||||
| if self.dir not in sys.path: | ||||
| sys.path.insert(0,self.dir) | ||||
| self.added = True | ||||
| else: | ||||
| self.added = False | ||||
| def __exit__(self, type, value, traceback): | ||||
| if self.added: | ||||
| try: | ||||
| sys.path.remove(self.dir) | ||||
| except ValueError: | ||||
| pass | ||||
| # Returning False causes any exceptions to be re-raised. | ||||
| return False | ||||