normalize path letter case

fix.py

"""
normalize_path_case convert path
c:\foo\bar.txt
to
C:\Foo\Bar.txt
(as the file presents at file system, include case resgister)
"""

def correct_case(where, name):
    if where.endswith(':'):
        where += '/'
    l = filter(lambda x: x.lower() == name.lower(), os.listdir(where))
    if (len(l) == 1):
        return l[0]
    return ''


def normalize_path_case(path):
    parts = os.path.abspath(path).split(os.sep)
    result = parts.pop(0).upper()
    for p in parts:
        c = correct_case(result, p)
        if not c:
            return ''
        result += '/' + c
    return result