michael@0: # This Source Code Form is subject to the terms of the Mozilla Public
michael@0: # License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0: # file, You can obtain one at http://mozilla.org/MPL/2.0/.
michael@0: 
michael@0: import posixpath
michael@0: import os
michael@0: import re
michael@0: 
michael@0: '''
michael@0: Like os.path, with a reduced set of functions, and with normalized path
michael@0: separators (always use forward slashes).
michael@0: Also contains a few additional utilities not found in os.path.
michael@0: '''
michael@0: 
michael@0: 
michael@0: def normsep(path):
michael@0:     '''
michael@0:     Normalize path separators, by using forward slashes instead of whatever
michael@0:     os.sep is.
michael@0:     '''
michael@0:     if os.sep != '/':
michael@0:         path = path.replace(os.sep, '/')
michael@0:     return path
michael@0: 
michael@0: 
michael@0: def relpath(path, start):
michael@0:     rel = normsep(os.path.relpath(path, start))
michael@0:     return '' if rel == '.' else rel
michael@0: 
michael@0: 
michael@0: def abspath(path):
michael@0:     return normsep(os.path.abspath(path))
michael@0: 
michael@0: 
michael@0: def join(*paths):
michael@0:     return normsep(os.path.join(*paths))
michael@0: 
michael@0: 
michael@0: def normpath(path):
michael@0:     return posixpath.normpath(normsep(path))
michael@0: 
michael@0: 
michael@0: def dirname(path):
michael@0:     return posixpath.dirname(normsep(path))
michael@0: 
michael@0: 
michael@0: def commonprefix(paths):
michael@0:     return posixpath.commonprefix([normsep(path) for path in paths])
michael@0: 
michael@0: 
michael@0: def basename(path):
michael@0:     return os.path.basename(path)
michael@0: 
michael@0: 
michael@0: def splitext(path):
michael@0:     return posixpath.splitext(normsep(path))
michael@0: 
michael@0: 
michael@0: def split(path):
michael@0:     '''
michael@0:     Return the normalized path as a list of its components.
michael@0:         split('foo/bar/baz') returns ['foo', 'bar', 'baz']
michael@0:     '''
michael@0:     return normsep(path).split('/')
michael@0: 
michael@0: 
michael@0: def basedir(path, bases):
michael@0:     '''
michael@0:     Given a list of directories (bases), return which one contains the given
michael@0:     path. If several matches are found, the deepest base directory is returned.
michael@0:         basedir('foo/bar/baz', ['foo', 'baz', 'foo/bar']) returns 'foo/bar'
michael@0:         ('foo' and 'foo/bar' both match, but 'foo/bar' is the deepest match)
michael@0:     '''
michael@0:     path = normsep(path)
michael@0:     bases = [normsep(b) for b in bases]
michael@0:     if path in bases:
michael@0:         return path
michael@0:     for b in sorted(bases, reverse=True):
michael@0:         if b == '' or path.startswith(b + '/'):
michael@0:             return b
michael@0: 
michael@0: 
michael@0: re_cache = {}
michael@0: 
michael@0: def match(path, pattern):
michael@0:     '''
michael@0:     Return whether the given path matches the given pattern.
michael@0:     An asterisk can be used to match any string, including the null string, in
michael@0:     one part of the path:
michael@0:         'foo' matches '*', 'f*' or 'fo*o'
michael@0:     However, an asterisk matching a subdirectory may not match the null string:
michael@0:         'foo/bar' does *not* match 'foo/*/bar'
michael@0:     If the pattern matches one of the ancestor directories of the path, the
michael@0:     patch is considered matching:
michael@0:         'foo/bar' matches 'foo'
michael@0:     Two adjacent asterisks can be used to match files and zero or more
michael@0:     directories and subdirectories.
michael@0:         'foo/bar' matches 'foo/**/bar', or '**/bar'
michael@0:     '''
michael@0:     if not pattern:
michael@0:         return True
michael@0:     if not pattern in re_cache:
michael@0:         pattern = re.escape(pattern)
michael@0:         pattern = re.sub(r'(^|\\\/)\\\*\\\*\\\/', r'\1(?:.+/)?', pattern)
michael@0:         pattern = re.sub(r'(^|\\\/)\\\*\\\*$', r'(?:\1.+)?', pattern)
michael@0:         pattern = pattern.replace(r'\*', '[^/]*') + '(?:/.*)?$'
michael@0:         re_cache[pattern] = re.compile(pattern)
michael@0:     return re_cache[pattern].match(path) is not None
michael@0: 
michael@0: 
michael@0: def rebase(oldbase, base, relativepath):
michael@0:     '''
michael@0:     Return relativepath relative to base instead of oldbase.
michael@0:     '''
michael@0:     if base == oldbase:
michael@0:         return relativepath
michael@0:     if len(base) < len(oldbase):
michael@0:         assert basedir(oldbase, [base]) == base
michael@0:         relbase = relpath(oldbase, base)
michael@0:         result = join(relbase, relativepath)
michael@0:     else:
michael@0:         assert basedir(base, [oldbase]) == oldbase
michael@0:         relbase = relpath(base, oldbase)
michael@0:         result = relpath(relativepath, relbase)
michael@0:     result = normpath(result)
michael@0:     if relativepath.endswith('/') and not result.endswith('/'):
michael@0:         result += '/'
michael@0:     return result