import os, tarfile, tempfile, shutil

temp_dir = tempfile.mkdtemp()
os.chdir(temp_dir)

short_dir_path1 = 'a'
short_dir_path2 = 'b/'
long_dir_path1 = 'a' * 101
long_dir_path2 = ('b' * 101) + '/'

os.mkdir(short_dir_path1)
os.mkdir(short_dir_path2)
os.mkdir(long_dir_path1)
os.mkdir(long_dir_path2)

tf = tarfile.open('test.tar', 'w')
tf.add(short_dir_path1)
tf.add(short_dir_path2)
tf.add(long_dir_path1)
tf.add(long_dir_path2)
tf.close()

tf = tarfile.open('test.tar')

# For short names I need to omit the trailing slash
tf.getmember(short_dir_path1) # This works, no trailing slash
try:
    tf.getmember(short_dir_path2) # This fails due to trailing slash
except KeyError:
    pass
else:
    print "KeyError not raised"
tf.getmember('b') # Omitting the trailing slash works

# For long names I need to include the trailing slash
try:
    tf.getmember(long_dir_path1) # Fails due to lack of trailing slash
except KeyError:
    pass
else:
    print "KeyError not raised"
tf.getmember(long_dir_path1 + '/') # Works if I include it
tf.getmember(long_dir_path2) # Also works since it has trailing slash

# This is a work around for consistent behavior (only in 2.7, as 2.6 lacks 
# the 'normalize' keywork)
tf._getmember(long_dir_path1, normalize=True) 

shutil.rmtree(temp_dir)