test_charmapcodec
abc == abc: OK
abcdef == abcdef: OK
defabc == defabc: OK
dabcf == dabcf: OK
dabcfabc == dabcfabc: OK
abc == abc: OK
abcdef == abcdef: OK
defabc == defabc: OK
dabcf == dabcf: OK
dabcfabc == dabcfabc: OK
def == def: OK
def == def: OK
df == df: OK
df == df: OK
\001 maps to undefined: OK