bpo-29240: On FreeBSD, if the LC_CTYPE locale is "C" or "POSIX",
writing and reading non-ASCII bytes into/from a TTY works,
but readline or ncurses ignores non-ASCII bytes on read.
Add new fuctions ignoring the UTF-8 mode:
* _Py_DecodeCurrentLocale()
* _Py_EncodeCurrentLocale()
* _PyUnicode_DecodeCurrentLocaleAndSize()
* _PyUnicode_EncodeCurrentLocale()
Modify the readline module to use these functions.
Re-enable test_readline.test_nonascii().
Skip the test which fails on FreeBSD with POSIX locale.
Skip the test to fix FreeBSD buildbots, until a fix can be found, so
the buildbots can catch other regressions.
Turns out that history-size was added in readline 6.0. This explain why
this tests fail on FreeBSD when using readline 5.2. We skip now the
history size if readline does not support it.
See https://cnswww.cns.cwru.edu/php/chet/readline/CHANGES for
details.
If history-length is set in .inputrc, and the history file is double the
history size (or more), history_get(N) returns NULL, and python
segfaults. Fix that by checking for NULL return value.
It seems that the root cause is incorrect handling of bigger history in
readline, but Python should not segfault even if readline returns
unexpected value.
This issue affects only GNU readline. When using libedit emulation
system history size option does not work.
I have compared output between pre- and post-patch runs of these tests
to make sure there's nothing missing and nothing broken, on both
Windows and Linux. The only differences I found were actually tests
that were previously *not* run.
