Cannot create partial versions

[vstojkovic]

If I pass '2.0' to the Version constructor, I get a ValueError regardless of whether I specified partial=True or not. I suspect that this is because version_re and partial_version_re are completely identical.

If this is intended behavior, then the documentation should be fixed to reflect that.

[rbarrois]

Indeed, the documentation is not very clear on that topic.

A partial Version is mostly used for the SpecItem class, it is mostly a distinction between ==2.0.0 (doesn't match 2.0.0+1) and ~=2.0.0 (matches 2.0.0+1).

That's not a very useful behaviour, my plan on this topic is:

1. Add support for coercing arbitrary version strings into semver-compatible ones
2. Move that code into a private part of SpecItem.

[cvrebert]

The docs are just plain wrong on the topic. They claim:

In order to define “relaxed” version strings, you must pass in partial=True:

>> v = semantic_version.Version('0.1', partial=True)
>> list(v)
[0, 1, None, None, None]

In reality:

Python 2.7.3 (default, Feb  5 2013, 11:06:02) 
[GCC 4.2.1 Compatible Apple Clang 4.0 ((tags/Apple/clang-421.0.60))] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import semantic_version
>>> v = semantic_version.Version('0.1', partial=True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/chris.rebert/envs/frank/lib/python2.7/site-packages/semantic_version/base.py", line 64, in __init__
    major, minor, patch, prerelease, build = self.parse(version_string, partial)
  File "/Users/chris.rebert/envs/frank/lib/python2.7/site-packages/semantic_version/base.py", line 86, in parse
    raise ValueError('Invalid version string: %r' % version_string)
ValueError: Invalid version string: '0.1'

[vstojkovic]

Thanks!