Create a _metadata.py file to re-use version number and author

This makes it so the version number only needs to be bumped in one
location (and it's named clearly) instead of 3.

Can be modified in the future if we want to add more fields,
like a date. There's also the possibility to auto-update that file with
git tags but might be a bit overkill for now.

docs/conf.py

@@ -15,6 +15,9 @@
 
 sys.path.insert(0, os.path.abspath('..'))
 
+meta = {}
+exec(open(os.path.abspath('../vsutil/_metadata.py')).read(), meta)
+
 
 # -- Project information -----------------------------------------------------
 
@@ -23,7 +26,7 @@
 author = 'Irrational Encoding Wizardry'
 
 # The full version, including alpha/beta/rc tags
-version = release = '0.5.0'
+version = release = meta['__version__']
 
 
 # -- General configuration ---------------------------------------------------

setup.py

@@ -1,5 +1,19 @@
 from setuptools import setup, find_packages
 from setuptools.command.test import test
+from distutils.util import convert_path
+
+# We can't import the submodule normally as that would "run" the main module
+# code while the setup script is meant to *build* the module.
+
+# Besides preventing a whole possible mess of issues with an un-built package,
+# this also prevents the vapoursynth import which breaks the docs on RTD.
+
+# convert_path is used here because according to the distutils docs:
+# '...filenames in the setup script are always supplied in Unix
+# style, and have to be converted to the local convention before we can
+# actually use them in the filesystem.'
+meta = {}
+exec(open(convert_path('vsutil/_metadata.py')).read(), meta)
 
 
 class DiscoverTest(test):
@@ -20,15 +34,15 @@ def run_tests(self):
 
 setup(
     name='vsutil',
-    version='0.5.0',
+    version=meta['__version__'],
     packages=find_packages(exclude=['tests']),
     package_data={
         'vsutil': ['py.typed']
     },
     url='https://encode.moe/vsutil',
     license='MIT',
-    author='kageru',
-    author_email='[email protected]',
+    author=meta['__author__'].split()[0],
+    author_email=meta['__author__'].split()[1][1:-1],
     description='A collection of general-purpose Vapoursynth functions to be reused in modules and scripts.',
     install_requires=[
         "vapoursynth"

vsutil/__init__.py

@@ -14,3 +14,8 @@
 __all__ = []
 for _pkg in _mods:
     __all__ += __import__(__name__ + '.' + _pkg, fromlist=_mods).__all__
+
+try:
+    from ._metadata import __author__, __version__
+except ImportError:
+    __author__ = __version__ = 'unknown'

vsutil/_metadata.py

@@ -0,0 +1,2 @@
+__author__ = 'kageru <[email protected]>'
+__version__ = '0.5.0'