issue/inconsistent behavior for all *. rules

[theagilehacker]

if there is a rule like:
*.abc.com
I would expect that if you give it
substuf.def.abc.com that the public suffix should be def.abc.com.

from publicsuffixlist import PublicSuffixList

# RULES TESTED:
# *.awdev.ca
# *.advisor.ws
#
# *.compute.amazonaws.com
# *.compute-1.amazonaws.com
# *.compute.amazonaws.com.cn
#
# *.elb.amazonaws.com
# *.elb.amazonaws.com.cn

psl = PublicSuffixList()
input = [
    'test.awdev.ca',
    'test.advisor.ws',
    
    'test.compute.amazonaws.com',
    'test.compute-1.amazonaws.com',
    'test.compute.amazonaws.com.cn',
    
    'test.elb.amazonaws.com',
    'test.amazonaws.com.cn',
    
    # add another level and it gets weird
    'sub.test.awdev.ca',
    'sub.test.advisor.ws',
    
    'sub.test.compute.amazonaws.com',
    'sub.test.compute-1.amazonaws.com',
    'sub.test.compute.amazonaws.com.cn',

    'sub.test.elb.amazonaws.com',
    'sub.test.amazonaws.com.cn',
]


output = [(i, psl.privatesuffix(i)) for i in input]

for t in output:
    print(f'{t[0]} -> {t[1]}')

Output from the run:

test.awdev.ca -> None
test.advisor.ws -> None
test.compute.amazonaws.com -> None
test.compute-1.amazonaws.com -> None
test.compute.amazonaws.com.cn -> None
test.elb.amazonaws.com -> None
test.amazonaws.com.cn -> amazonaws.com.cn
sub.test.awdev.ca -> sub.test.awdev.ca
sub.test.advisor.ws -> sub.test.advisor.ws
sub.test.compute.amazonaws.com -> sub.test.compute.amazonaws.com
sub.test.compute-1.amazonaws.com -> sub.test.compute-1.amazonaws.com
sub.test.compute.amazonaws.com.cn -> sub.test.compute.amazonaws.com.cn
sub.test.elb.amazonaws.com -> sub.test.elb.amazonaws.com
sub.test.amazonaws.com.cn -> amazonaws.com.cn

I would have expected the first set to return the domains unchanged and the second set to return the part minus the sub. part.

in either case the behavior is inconsistent for 2 reasons:

1. test.amazonaws.com.cn -> amazonaws.com.cn the return was not None like all the others.
2. why are all the domains with sub returning unchanged? again with the sub.test.amazonaws.com.cn -> amazonaws.com.cn behaving differently.

[ko-zu]

privatesuffix() returns None if input has no private part. test.amazonaws.com.cn does not match *.elb.amazonaws.com.cn so com.cn should be public part.
Please try publicsuffix() instead privatesuffix() to see where the PSL matches input.

[theagilehacker]

Thank you for responding so quickly. I will try publicsuffix() and let you know what I get on my actual data.

[theagilehacker]

You are correct there is not inconsistency. I messed up my test by accidentally removing the elb from that test domain passed in. So YAY, and egg on my face then.