Package SCons :: Package compat
[hide private]
[frames] | no frames]

Source Code for Package SCons.compat

  1  # 
  2  # Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 The SCons Foundation 
  3  # 
  4  # Permission is hereby granted, free of charge, to any person obtaining 
  5  # a copy of this software and associated documentation files (the 
  6  # "Software"), to deal in the Software without restriction, including 
  7  # without limitation the rights to use, copy, modify, merge, publish, 
  8  # distribute, sublicense, and/or sell copies of the Software, and to 
  9  # permit persons to whom the Software is furnished to do so, subject to 
 10  # the following conditions: 
 11  # 
 12  # The above copyright notice and this permission notice shall be included 
 13  # in all copies or substantial portions of the Software. 
 14  # 
 15  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
 16  # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
 17  # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 18  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
 19  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
 20  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
 21  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
 22  # 
 23   
 24  __doc__ = """ 
 25  SCons compatibility package for old Python versions 
 26   
 27  This subpackage holds modules that provide backwards-compatible 
 28  implementations of various things that we'd like to use in SCons but which 
 29  only show up in later versions of Python than the early, old version(s) 
 30  we still support. 
 31   
 32  This package will be imported by other code: 
 33   
 34      import SCons.compat 
 35   
 36  But other code will not generally reference things in this package through 
 37  the SCons.compat namespace.  The modules included here add things to 
 38  the __builtin__ namespace or the global module list so that the rest 
 39  of our code can use the objects and names imported here regardless of 
 40  Python version. 
 41   
 42  Simply enough, things that go in the __builtin__ name space come from 
 43  our builtins module. 
 44   
 45  The rest of the things here will be in individual compatibility modules 
 46  that are either: 1) suitably modified copies of the future modules that 
 47  we want to use; or 2) backwards compatible re-implementations of the 
 48  specific portions of a future module's API that we want to use. 
 49   
 50  GENERAL WARNINGS:  Implementations of functions in the SCons.compat 
 51  modules are *NOT* guaranteed to be fully compliant with these functions in 
 52  later versions of Python.  We are only concerned with adding functionality 
 53  that we actually use in SCons, so be wary if you lift this code for 
 54  other uses.  (That said, making these more nearly the same as later, 
 55  official versions is still a desirable goal, we just don't need to be 
 56  obsessive about it.) 
 57   
 58  We name the compatibility modules with an initial '_scons_' (for example, 
 59  _scons_subprocess.py is our compatibility module for subprocess) so 
 60  that we can still try to import the real module name and fall back to 
 61  our compatibility module if we get an ImportError.  The import_as() 
 62  function defined below loads the module as the "real" name (without the 
 63  '_scons'), after which all of the "import {module}" statements in the 
 64  rest of our code will find our pre-loaded compatibility module. 
 65  """ 
 66   
 67  __revision__ = "src/engine/SCons/compat/__init__.py 3266 2008/08/12 07:31:01 knight" 
 68   
69 -def import_as(module, name):
70 """ 71 Imports the specified module (from our local directory) as the 72 specified name. 73 """ 74 import imp 75 import os.path 76 dir = os.path.split(__file__)[0] 77 file, filename, suffix_mode_type = imp.find_module(module, [dir]) 78 imp.load_module(name, file, filename, suffix_mode_type)
79 80 import builtins 81 82 try: 83 import hashlib 84 except ImportError: 85 # Pre-2.5 Python has no hashlib module. 86 try: 87 import_as('_scons_hashlib', 'hashlib') 88 except ImportError: 89 # If we failed importing our compatibility module, it probably 90 # means this version of Python has no md5 module. Don't do 91 # anything and let the higher layer discover this fact, so it 92 # can fall back to using timestamp. 93 pass 94 95 try: 96 set 97 except NameError: 98 # Pre-2.4 Python has no native set type 99 try: 100 # Python 2.2 and 2.3 can use the copy of the 2.[45] sets module 101 # that we grabbed. 102 import_as('_scons_sets', 'sets') 103 except (ImportError, SyntaxError): 104 # Python 1.5 (ImportError, no __future_ module) and 2.1 105 # (SyntaxError, no generators in __future__) will blow up 106 # trying to import the 2.[45] sets module, so back off to a 107 # custom sets module that can be discarded easily when we 108 # stop supporting those versions. 109 import_as('_scons_sets15', 'sets') 110 import __builtin__ 111 import sets 112 __builtin__.set = sets.Set 113 114 import fnmatch 115 try: 116 fnmatch.filter 117 except AttributeError: 118 # Pre-2.2 Python has no fnmatch.filter() function.
119 - def filter(names, pat):
120 """Return the subset of the list NAMES that match PAT""" 121 import os,posixpath 122 result=[] 123 pat = os.path.normcase(pat) 124 if not fnmatch._cache.has_key(pat): 125 import re 126 res = fnmatch.translate(pat) 127 fnmatch._cache[pat] = re.compile(res) 128 match = fnmatch._cache[pat].match 129 if os.path is posixpath: 130 # normcase on posix is NOP. Optimize it away from the loop. 131 for name in names: 132 if match(name): 133 result.append(name) 134 else: 135 for name in names: 136 if match(os.path.normcase(name)): 137 result.append(name) 138 return result
139 fnmatch.filter = filter 140 del filter 141 142 try: 143 import itertools 144 except ImportError: 145 # Pre-2.3 Python has no itertools module. 146 import_as('_scons_itertools', 'itertools') 147 148 # If we need the compatibility version of textwrap, it must be imported 149 # before optparse, which uses it. 150 try: 151 import textwrap 152 except ImportError: 153 # Pre-2.3 Python has no textwrap module. 154 import_as('_scons_textwrap', 'textwrap') 155 156 try: 157 import optparse 158 except ImportError: 159 # Pre-2.3 Python has no optparse module. 160 import_as('_scons_optparse', 'optparse') 161 162 import shlex 163 try: 164 shlex.split 165 except AttributeError: 166 # Pre-2.3 Python has no shlex.split() function. 167 # 168 # The full white-space splitting semantics of shlex.split() are 169 # complicated to reproduce by hand, so just use a compatibility 170 # version of the shlex module cribbed from Python 2.5 with some 171 # minor modifications for older Python versions. 172 del shlex 173 import_as('_scons_shlex', 'shlex') 174 175 try: 176 import subprocess 177 except ImportError: 178 # Pre-2.4 Python has no subprocess module. 179 import_as('_scons_subprocess', 'subprocess') 180 181 import sys 182 try: 183 sys.version_info 184 except AttributeError: 185 # Pre-1.6 Python has no sys.version_info 186 import string 187 version_string = string.split(sys.version)[0] 188 version_ints = map(int, string.split(version_string, '.')) 189 sys.version_info = tuple(version_ints + ['final', 0]) 190 191 try: 192 import UserString 193 except ImportError: 194 # Pre-1.6 Python has no UserString module. 195 import_as('_scons_UserString', 'UserString') 196