chardet v4.0.0 Release Notes

Release Date: 2020-12-10 // 10 months ago
  • ๐Ÿš€ โš ๏ธ This will be the last release of chardet to support Python 2.7. chardet 5.0 will only support 3.6+ โš ๏ธ

    Major Changes

    ๐Ÿš€ This release is multiple years in the making, and provides some quality of life improvements to chardet. The primary user-facing changes are:

    ๐Ÿ‘€ 1. Single-byte charset probers now use nested dictionaries under the hood, so they are usually a little faster than before. (See #121 for details)

    1. The CharsetGroupProber class now properly short-circuits when one of the probers in the group is considered a definite match. This lead to a substantial speedup.
    2. There is now a chardet.detect_all function that returns a list of possible encodings for the input with associated confidences. ๐Ÿ‘ 4. We have dropped support for Python 2.6, 3.4, and 3.5 as they are all past end-of-life.

    ๐Ÿš€ The changes in this release have also laid the groundwork for retraining the models to make them more accurate, and to support some more encodings/languages (see #99 for progress). This is our main focus for chardet 5.0 (beyond dropping Python 2 support).

    Benchmarks

    โš™ Running on a MacBook Pro (15-inch, 2018) with 2.2GHz 6-core i7 processor and 32GB RAM

    old version (chardet 3.0.4)

    Benchmarking chardet 3.0.4 on CPython 3.7.5 (default, Sep 8 2020, 12:19:42)
    [Clang 11.0.3 (clang-1103.0.32.62)]
    --------------------------------------------------------------------------------
    Calls per second for each encoding:
    ascii: 25559.439366240098
    big5: 7.187002209518091
    cp932: 4.71090956645177
    cp949: 2.937256786994428
    euc-jp: 4.870580412090848
    euc-kr: 6.6910755971933416
    euc-tw: 87.71098043480079
    gb2312: 6.614302607154443
    ibm855: 27.595893549680685
    ibm866: 29.93483661732791
    iso-2022-jp: 3379.5052775763434
    iso-2022-kr: 26181.67290886392
    iso-8859-1: 120.63424740403983
    iso-8859-5: 32.65106262196898
    iso-8859-7: 62.480089080556084
    koi8-r: 13.72481001727257
    maccyrillic: 33.018537255804496
    shift_jis: 4.996013583677438
    tis-620: 14.323112928341818
    utf-16: 166771.53081510935
    utf-32: 198782.18009478672
    utf-8: 13.966236809766901
    utf-8-sig: 193732.28637413395
    windows-1251: 23.038910006925768
    windows-1252: 99.48409117053738 
    windows-1255: 6.336261495718825
    
    Total time: 357.05358052253723s (10.054513372323958 calls per second)
    

    ๐Ÿ†• new version (chardet 4.0.0)

    Benchmarking chardet 4.0.0 on CPython 3.7.5 (default, Sep 8 2020, 12:19:42)
    [Clang 11.0.3 (clang-1103.0.32.62)]
    --------------------------------------------------------------------------------
    .......................................................................................................................................................................................................................................................................................................................................................................
    Calls per second for each encoding:
    ascii: 38176.31067961165
    big5: 12.86915132656389
    cp932: 4.656400877065864
    cp949: 7.282976434315926
    euc-jp: 4.329381447610525
    euc-kr: 8.16386823884839
    euc-tw: 90.230745070368
    gb2312: 14.248865889128146
    ibm855: 33.30225548069821
    ibm866: 44.181691968506
    iso-2022-jp: 3024.2295767539117
    iso-2022-kr: 25055.57945041816
    iso-8859-1: 59.25262902122995
    iso-8859-5: 39.7069713674529
    iso-8859-7: 61.008422013862194
    koi8-r: 41.21560517643845
    maccyrillic: 31.402474369805002
    shift_jis: 4.9091652743515155
    tis-620: 14.408875278821073
    utf-16: 177349.00634249471
    utf-32: 186413.51111111112
    utf-8: 108.62174360115105
    utf-8-sig: 181965.46637744035
    windows-1251: 43.16933400329809
    windows-1252: 211.27653358317968
    windows-1255: 16.15113643694104
    
    Total time: 268.0230791568756s (13.394368915143872 calls per second)
    

    ๐Ÿš€ Thank you to @aaaxx, @edumco, @hrnciar, @hroncok, @jdufresne, @mdamien, @saintamh , @xeor for submitting pull requests, to all of our users for being patient with how long this release has taken.

    Full changelog


Previous changes from v3.0.4

  • ๐Ÿ›  This minor bugfix release just fixes some packaging and documentation issues:

    • ๐Ÿ›  Fix issue with setup.py where pytest_runner was always being installed. (PR #119, thanks @zmedico)
    • โœ… Make sure test.py is included in the manifest (PR #118, thanks @zmedico)
    • ๐Ÿ›  Fix a bunch of old URLs in the README and other docs. (PRs #123 and #129, thanks @qfan and @jdufresne)
    • ๐Ÿ“š Update documentation to no longer imply we test/support Python 3 versions before 3.3 (PR #130, thanks @jdufresne)