updated with latest feedback + PEP 345 changes

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Tarek Ziadé 2009-10-20 08:35:18 +00:00
parent 1c4110d282
commit 2b2e353c74
1 changed files with 46 additions and 23 deletions

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@ -19,22 +19,29 @@ Distutils.
Motivation
==========
Distutils will soon extend the metadata standard, by including the
`install_requires` field from Setuptools [#requires]_ among other changes.
Distutils will soon extend the metadata standard, by including an
``install_requires``-like field from Setuptools [#requires]_ among
other changes. This field will be called ``Requires-Dist``.
These changes are a work in progress in PEP 345 [#pep345]_, but validating
the current PEP is mandatory to continue the work.
These changes are located in PEP 345 [#pep345]_.
The `install_requires` field will allow a package to define a dependency on
another package and optionally restrict this dependency to a set of
compatible versions.
The ``Requires-Dist`` field will allow a package to define a dependency on
another package and optionally restrict this dependency to a set of
compatible versions, so one may write::
Requires-Dist: zope.interface (>3.5.0)
This means that the distribution requires ``zope.interface``, as long as its
version is superior to ``3.5.0``.
That's why Distutils needs to provide a robust standard and reference
implementation to compare versions numbers.
version scheme, and an API to provide version comparisons.
This will also provide to the community a convention for their package
versioning needs.
This PEP describes a new version scheme that will be added in Distutils.
Of course developers are **not** required to conform to this scheme, but
it is suggested to use it as a standard for interoperability between the
existing Python distributions installers.
Current status
==============
@ -246,12 +253,11 @@ The new versioning algorithm
During Pycon, members of the Python, Ubuntu and Fedora community worked on
a version standard that would be acceptable for everyone.
It's currently called `verlib` and a prototype lives here :
http://bitbucket.org/tarek/distutilsversion/src/
It's currently called `verlib` and a prototype lives at [#prototype]_.
The pseudo-format supported is::
N.N[.N]+[abc]N[.N]+[.postN+][.devN+]
N.N[.N]+[abc]N[.N]+[.postN+][.devN+]
Some examples probably make it clearer::
@ -267,16 +273,19 @@ Some examples probably make it clearer::
... < V('1.0c1')
... < V('1.0.dev456')
... < V('1.0')
... < V('1.0.post623.dev456')
... < V('1.0.post456.dev34')
... < V('1.0.post456'))
True
The trailing ".dev123" is for pre-releases. The ".post123" is for
The trailing ``.dev123`` is for pre-releases. The ``.post123`` is for
post-releases -- which apparently is used by a number of projects out there
(e.g. Twisted [#twisted]_). For example *after* a "1.2.0" release there might
be a "1.2.0-r678" release. We used "post" instead of "r" because the "r" is
ambiguous as to whether it indicates a pre- or post-release.
Last ".post623.dev456" is a development version of a post-release.
(e.g. Twisted [#twisted]_). For example *after* a ``1.2.0`` release there might
be a ``1.2.0-r678`` release. We used ``post`` instead of ``r`` because the
``r`` is ambiguous as to whether it indicates a pre- or post-release.
Last, ``.post456.dev34`` indicates a dev parker for a post release, that sorts
before a ``.post345`` marker. This can be used to do development versions
of post releases.
``verlib`` provides a ``RationalVersion`` class and a
``suggest_rational_version`` function.
@ -310,7 +319,6 @@ Each part is a tuple and there are three parts:
- the main version part
- the pre-release part
- the `postdev` marker part
Examples ::
@ -326,10 +334,22 @@ Examples ::
>>> str(version)
'1.0c4.dev34'
suggest_rational_version
------------------------
XXX explain here suggest_rational_version
``suggest_rational_version`` is a function that suggests a rational version
close to the given version string. If you have a version string that isn't
rational (i.e. ``RationalVersion`` doesn't like it) then you might be able
to get an equivalent (or close) rational version from this function.
This does a number of simple normalizations to the given string, based
on observation of versions currently in use on PyPI. Given a dump of those
version during PyCon 2009, 4287 of them:
- 2312 (53.93%) match RationalVersion without change with the automatic
suggestion
- 3474 (81.04%) match when using this suggestion method
References
@ -365,8 +385,11 @@ References
.. [#pep345]
http://svn.python.org/projects/peps/branches/jim-update-345/pep-0345.txt
Aknowledgments
==============
.. [#prototype]
http://bitbucket.org/tarek/distutilsversion/
Acknowledgments
===============
Trent Mick, Matthias Klose, Phillip Eby, and many people at Pycon and
Distutils-SIG.