tests: fix bytes literals in test-fncache.t # skip-blame just b prefixes Differential Revision: https://phab.mercurial-scm.org/D2612

scmutil: avoid using basestring and add explicit handling of unicodes This resolves some Python 3 defects, and I don't think it is a meaningful behavior change in Python 2. Differential Revision: https://phab.mercurial-scm.org/D2611

tests: fix inline extension bytes in test-ssh-proto-unbundle.t # skip-blame just b prefixes Differential Revision: https://phab.mercurial-scm.org/D2610

hghave: fix up clang-libfuzzer regex to be bytes Fixes this check on Python 3. # skip-blame just a b prefix Differential Revision: https://phab.mercurial-scm.org/D2607

py3: accept both unicode and byte strings as filename carried by IOError Follows up 77f98867538f. We could assume there's no bytes filename in our codebase, but it's probably better to not raise UnicodeError because of a unicode filename.

py3: back out c77c925987d7 to store bytes filename in IOError Appears that this is how Python 3 works.

largefiles: headers and values need to be sysstrs, add r prefixes # skip-blame just some r prefixes Differential Revision: https://phab.mercurial-scm.org/D2606

cext: accept arguments as Py_buffer The s*/y* value formatters receive a Py_buffer instead of a char *. This value format is more flexible in the types that it allows. We change bdiff() to accept any object that conforms to the buffer protocol. We validate the buffers are contiguous and have a single dimension. This allows memoryview instances to be handled by the function, so we revert a recent change to cast arguments to bytes before calling this function. Differential Revision: https://phab.mercurial-scm.org/D2587