Changelog

1.0 (2026-05-19)

Added

• New parser which preserves case and leading zeros.

  v1.0

  >>> Version.parse("2026.05BETA")
  <Version '2026.05BETA'>
  

  v0.5

  >>> Version.parse("2026.05BETA")
  <Version '2026.5beta'>
  

• Improved error messages.

  v1.0

  >>> Version.parse("abc")
  Traceback (most recent call last):
  ...
  parver.NoLeadingNumberError: Expected a release number at position 0, found 'a'
  
  >>> Version.parse("1.2alpha1", strict=True)
  Traceback (most recent call last):
  ...
  parver.StrictPreTagError: Pre-release tag 'alpha' is not allowed in strict mode; use 'a'
  
  >>> Version.parse("1.2-1", strict=True)
  Traceback (most recent call last):
  ...
  parver.StrictSegmentError: Implicit post-release shorthand '-1' is not allowed
  in strict mode; use '.post1'
  
  >>> Version.parse("1+ABC", strict=True)
  Traceback (most recent call last):
  ...
  parver.InvalidLocalError: Local version segment 'ABC' is not allowed in strict
  mode: must be lowercase alphanumeric; use 'abc'
  

  v0.5

  >>> Version.parse("abc")
  Traceback (most recent call last):
  ...
  parver.ParseError: Expected v or int at position (1, 1) => '*abc'.
  
  >>> Version.parse("1.2alpha1", strict=True)
  Traceback (most recent call last):
  ...
  parver.ParseError: Expected pre_post_num at position (1, 5) => '1.2a*lpha1'.
  
  >>> Version.parse("1.2-1", strict=True)
  Traceback (most recent call last):
  ...
  parver.ParseError: Expected dot or 'a' or 'b' or 'rc' or sep or '+' or EOF at
  position (1, 4) => '1.2*-1'.
  
  >>> Version.parse("1+ABC", strict=True)
  Traceback (most recent call last):
  ...
  parver.ParseError: Expected alpha or int at position (1, 3) => '1+*ABC'.
  

• The following methods preserve leading zeros, and gain a new width argument.

  • bump_epoch()

  • bump_release()

  • bump_release_to()

  • set_release()

  • bump_pre()

  • bump_post()

  • bump_dev()

• Support for non-standard development release tags, such as DEV, across:

  • dev_tag

  • The dev_tag argument to Version

  • The tag argument to bump_dev()

• Support for Python 3.13 and 3.14.

Changed

• BREAKING CHANGE. The Version constructor is now keyword-only.

• BREAKING CHANGE. Version.parse() now requires strict to be passed as a keyword argument.

• BREAKING CHANGE. Version.v now stores "v", "V", or None instead of True or False.

• BREAKING CHANGE. dev_sep was renamed to dev_sep1.

Removed

• Support for Python 3.8 and 3.9.

Fixed

• Development releases can now use a separator between dev and the following number as permitted by PEP 440. The separator is exposed as dev_sep2 and as a Version keyword argument (#33).

0.5 (2023-10-03)

Added

• Support for Python 3.12

Removed

• Support for Python 3.7

0.4 (2022-11-11)

Added

• Type hints.

Removed

• Support for Python 2.7, 3.5, and 3.6.

• __version__, __author__, and __email__ attributes from parver module. Use importlib.metadata instead.

0.3.1 (2020-09-28)

Added

• Grammar is parsed when first used to improve import time.

Fixed

• attrs deprecation warning. The minimum attrs version is now 19.2

• Errors raised for keyword-only argument errors on Python 3 did not have the right error message.

0.3 (2020-02-20)

Added

• Version.truncate method to remove trailing zeros from the release segment.

• Version now validates each item in the release sequence.

• Version.bump_epoch method.

• Add by keyword argument to bump_pre, bump_post, and bump_dev methods, which e.g. .bump_dev(by=-1).

Changed

• BREAKING CHANGE. The Version constructor now uses an empty string to represent an implicit zero instead of None.

  >>> Version(release=1, post='')
  <Version '1.post'>
  

Removed

• BREAKING CHANGE. Version.clear is no longer necessary. Use Version.replace(pre=None, post=None, dev=None) instead.

Fixed

• Version incorrectly allowed an empty release sequence.

• Version rejects bool for numeric components.

• Version rejects negative integers for numeric components.

• The strict parser no longer accepts local versions with - or _ separators, or uppercase letters.

• The strict parser no longer accepts numbers with leading zeros.

• The local version was only being converted to lowercase when parsing with strict=False. It is now always converted.

• The local version separators were not being normalized to use ..

0.2.1 (2018-12-31)

Fixed

• On Python 2, Version was incorrectly rejecting long integer values.

0.2 (2018-11-21)

Added

• Version.bump_release_to method for control over the value to bump to, e.g. for CalVer.

• Version.set_release method for finer control over release values without resetting subsequent indices to zero.

Changed

• BREAKING CHANGE. The argument to Version.bump_release is now a keyword only argument, e.g. Version.bump_release(index=0).

• The release parameter to Version now accepts any iterable.

Fixed

• Deprecation warnings about invalid escape sequences in _parse.py.

0.1.1 (2018-06-19)

Fixed

• Version accepted pre=None and post_tag=None, which produces an ambiguous version number. This is because an implicit pre-release number combined with an implicit post-release looks like a pre-release with a custom separator:

  >>> Version(release=1, pre_tag='a', pre=None, post_tag=None, post=2)
  <Version '1a-2'>
  >>> Version(release=1, pre_tag='a', pre_sep2='-', pre=2)
  <Version '1a-2'>
  

  The first form now raises a ValueError.

• Don’t allow post=None when post_tag=None. Implicit post releases cannot have implicit post release numbers.

0.1 (2018-05-20)

First release.