bpo-37596: Update test_deterministic_sets to correctly handle different string hash algorithms

[brandtbucher]

$ for HASH_ALGORITHM in siphash24 fnv
> do
>     ./configure --with-hash-algorithm=$HASH_ALGORITHM &> /dev/null
>     make -j &> /dev/null
>     ./python -c 'import sys; print(f"{sys.hash_info.algorithm = }")'
>     ./python -m test test_marshal
> done

sys.hash_info.algorithm = 'siphash24'
0:00:00 load avg: 3.28 Run tests sequentially
0:00:00 load avg: 3.28 [1/1] test_marshal

== Tests result: SUCCESS ==

1 test OK.

Total duration: 316 ms
Tests result: SUCCESS

sys.hash_info.algorithm = 'fnv'
0:00:00 load avg: 15.70 Run tests sequentially
0:00:00 load avg: 15.70 [1/1] test_marshal

== Tests result: SUCCESS ==

1 test OK.

Total duration: 311 ms
Tests result: SUCCESS

https://bugs.python.org/issue37596

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @brandtbucher for commit e72a25b 🤖

If you want to schedule another build, you need to add the ":hammer: test-with-buildbots" label again.

[gvanrossum]

So did you just try different strings until you found one that hashes the same under fnv and siphash24?? That's amazing. (I didn't even know we had all this machinery -- all I know is that we have "hash randomization" and that you can force the seed by setting an env var. :-)

[brandtbucher]

So did you just try different strings until you found one that hashes the same under fnv and siphash24?? That's amazing.

No, I just needed to find one that hashes in such a way that sets containing them have different orders under PYTHONHASHSEED=0 and PYTHONHASHSEED=1 for each algorithm! It's a much easier task. 🙃

(I didn't even know we had all this machinery -- all I know is that we have "hash randomization" and that you can force the seed by setting an env var. :-)

Same, I learned a lot about this stuff today!

[brandtbucher]

That buildbot's been failing for a while with that same error. I'll open an issue for it.

[bedevere-bot]

@brandtbucher: Please replace # with GH- in the commit message next time. Thanks!

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Fedora Stable LTO 3.x has failed when building commit 3beef86.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/271/builds/562) and take a look at the build logs.
4. Check if the failure is related to this commit (3beef86) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/271/builds/562

Summary of the results of the build (if available):

== Tests result: ENV CHANGED ==

413 tests OK.

10 slowest tests:

• test_peg_generator: 3 min 34 sec
• test_concurrent_futures: 2 min 31 sec
• test_gdb: 1 min 43 sec
• test_nntplib: 1 min 20 sec
• test_multiprocessing_spawn: 1 min 7 sec
• test_multiprocessing_forkserver: 58.9 sec
• test_asyncio: 56.2 sec
• test_multiprocessing_fork: 53.0 sec
• test_signal: 47.1 sec
• test_io: 37.1 sec

1 test altered the execution environment:
test_ftplib

13 tests skipped:
test_devpoll test_ioctl test_kqueue test_msilib test_ossaudiodev
test_startfile test_tix test_tk test_ttk_guionly test_winconsoleio
test_winreg test_winsound test_zipfile64

Total duration: 4 min 43 sec

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/threading.py", line 1009, in _bootstrap_inner
    self.run()
    ^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/test/test_ftplib.py", line 297, in run
    asyncore.loop(timeout=0.1, count=1)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asyncore.py", line 214, in loop
    poll_fun(timeout, map)
    ^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asyncore.py", line 157, in poll
    read(obj)
    ^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asyncore.py", line 94, in read
    obj.handle_error()
    ^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/test/test_ftplib.py", line 139, in handle_error
    raise Exception
    ^^^^^^^^^^^^^^^
Exception


Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asyncore.py", line 90, in read
    obj.handle_read_event()
    ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asyncore.py", line 427, in handle_read_event
    self.handle_read()
    ^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/asynchat.py", line 179, in handle_read
    self.found_terminator()
    ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/test/test_ftplib.py", line 134, in found_terminator
    method(arg)
    ^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/test/test_ftplib.py", line 159, in cmd_pasv
    conn, addr = sock.accept()
                 ^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-x86_64.lto/build/Lib/socket.py", line 293, in accept
    fd, addr = self._accept()
               ^^^^^^^^^^^^^^
TimeoutError: timed out