[MRG] Fix max hash deprecation warnings

[ctb]

In #1128, we deprecated direct use of max_hash attribute as of 3.5, slated for removal in 5.0. This PR cleans up the sourmash codebase so that the associated deprecation warnings do not come from internal code, at least 😄

Specifically, this PR -

• removes MinHash.max_hash from most code in sourmash, including tests.
• creates a new private _max_hash proprety on class MinHash.
• uses Minhash._max_hash in the few remaining places in the code base.

I also updated the screed version requirement in setup.cfg to v1.0.5, which removes another DeprecationWarning from old py2.7/3.6 code.

Fixes #1296, clean up deprecation warnings
Fixes #1297, update screed version

Checklist

• Is it mergeable?
• make test Did it pass the tests?
• make coverage Is the new code covered?
• Did it change the command-line interface? Only additions are allowed
  without a major version increment. Changing file formats also requires a
  major version number increment.
• Was a spellchecker run on the source code and documentation after
  changes were made?

[codecov]

Codecov Report

Merging #1301 (b821f76) into latest (3c1241b) will increase coverage by 5.26%.
The diff coverage is 93.93%.

@@            Coverage Diff             @@
##           latest    #1301      +/-   ##
==========================================
+ Coverage   88.70%   93.97%   +5.26%     
==========================================
  Files         125       98      -27     
  Lines       18293    14678    -3615     
  Branches     1438     1437       -1     
==========================================
- Hits        16226    13793    -2433     
+ Misses       1821      640    -1181     
+ Partials      246      245       -1     

Flag	Coverage Δ
python	93.97% <93.93%> (+<0.01%)	⬆️
rust	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/sourmash/compare.py	87.87% <ø> (ø)
src/sourmash/commands.py	82.39% <60.00%> (ø)
src/sourmash/minhash.py	94.54% <100.00%> (+0.36%)	⬆️
tests/test__minhash.py	99.26% <100.00%> (ø)
tests/test_cmd_signature.py	100.00% <100.00%> (ø)
tests/test_jaccard.py	98.91% <100.00%> (+<0.01%)	⬆️
tests/test_signature.py	94.97% <100.00%> (ø)
tests/test_sourmash_compute.py	100.00% <100.00%> (ø)
tests/test_sourmash_sketch.py	100.00% <100.00%> (ø)
src/core/src/ffi/signature.rs
... and 26 more

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[ctb]

ready for review @luizirber

[luizirber]

Next PR down the line from this one is removing max_hash from MinHash.__init__, and I think that will remove most of the uses of MinHash._max_hash too?

[ctb]

Next PR down the line from this one is removing max_hash from MinHash.__init__, and I think that will remove most of the uses of MinHash._max_hash too?

Do you mean, that SHOULD be the next PR down the line? I'm not sure I want to do that for 4.0; involves a few more changes, and might break pickled MinHash objects.

[luizirber]

Do you mean, that SHOULD be the next PR down the line? I'm not sure I want to do that for 4.0; involves a few more changes, and might break pickled MinHash objects.

I sure hope no one is depending on storing pickled MinHash objects 😬

[ctb]

On Thu, Feb 04, 2021 at 04:23:52PM -0800, Luiz Irber wrote: > Do you mean, that SHOULD be the next PR down the line? I'm not sure I want to do that for 4.0; involves a few more changes, and might break pickled MinHash objects. I sure hope no one is depending on storing pickled MinHash objects :grimacing:

I think I might be, in spacegraphcats 😁

[luizirber]

I sure hope no one is depending on storing pickled MinHash objects

I think I might be, in spacegraphcats

May be worth a look (faster and safer pickle): https://jcristharif.com/quickle/