Version information

We switched to the `release-branch-semver`_ version scheme. This only affects,

the version information for development builds. Their version number now

describes the targeted release, i.e. 3.5.0.dev820+g6768ef8c4c.d20210520

is 820 commits after the previous release and is scheduled to be officially

released as 3.5.0 later.

In addition to the string ``__version__``, there is now a namedtuple

``__version_info__`` as well, which is modelled after `sys.version_info`_.

Its primary use is safely comparing version information, e.g.

``if __version_info__ >= (3, 4, 2)``.

.. _release-branch-semver: https://github.com/pypa/setuptools_scm#version-number-construction

.. _sys.version_info: https://docs.python.org/3/library/sys.html#sys.version_info

_VersionInfo = namedtuple('_VersionInfo',

'major, minor, micro, releaselevel, serial')

def _parse_to_version_info(version_str):

"""

v = parse_version(version_str)

if v.pre is None and v.post is None and v.dev is None:

return _VersionInfo(v.major, v.minor, v.micro, 'final', 0)

elif v.dev is not None:

return _VersionInfo(v.major, v.minor, v.micro, 'alpha', v.dev)

elif v.pre is not None:

releaselevel = {

'a': 'alpha',

'b': 'beta',

'rc': 'candidate'}.get(v.pre[0], 'alpha')

return _VersionInfo(v.major, v.minor, v.micro, releaselevel, v.pre[1])

else:

# fallback for v.post: guess-next-dev scheme from setuptools_scm

return _VersionInfo(v.major, v.minor, v.micro + 1, 'alpha', v.post)

def _get_version():

"""Return the version string used for __version__."""

# Only shell out to a git subprocess if really needed, and not on a

# shallow clone, such as those used by CI, as the latter would trigger

# a warning from setuptools_scm.

root = Path(__file__).resolve().parents[2]

if (root / ".git").exists() and not (root / ".git/shallow").exists():

return setuptools_scm.get_version(

root=root,

version_scheme="post-release",

local_scheme="node-and-date",

fallback_version=_version.version,

)

else: # Get the version from the _version.py setuptools_scm file.

return _version.version

def __getattr__(name):

if name in ("__version__", "__version_info__"):

__version__ = _get_version()

global __version__info__ # cache it.

__version_info__ = _parse_to_version_info(__version__)

return __version__ if name == "__version__" else __version_info__

def test_parse_to_version_info(version_str, version_tuple):

assert matplotlib._parse_to_version_info(version_str) == version_tuple