python: Have setup.py read the version number without importing

Importing the notmuch module in setup.py is a no-no, and we want
to auto-generate the version number in the release process.

Outsource __VERSION__ to the new version.py which contains nothing else
and which can therefor easily be autogenerated. Have setup.py read in
the file via execfile and test if importing the version number actually
worked.

This should make all happy.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>

bindings/python/notmuch/__init__.py

@@ -57,6 +57,6 @@ from notmuch.message import Messages, Message
 from notmuch.thread import Threads, Thread
 from notmuch.tag import Tags
 from notmuch.globals import nmlib, STATUS, NotmuchError
+from notmuch.version import __VERSION__
 __LICENSE__ = "GPL v3+"
-__VERSION__ = '0.6'
 __AUTHOR__ = 'Sebastian Spaeth <Sebastian@SSpaeth.de>'

bindings/python/notmuch/version.py

@@ -0,0 +1,2 @@
+# This file is potentially auto-generated. Do not modify
+__VERSION__ = '0.6'

bindings/python/setup.py

@@ -4,18 +4,11 @@ import os
 import re
 from distutils.core import setup
 
-def get_version():
-    file = open('notmuch/__init__.py')
-    try:
-        for line in file:
-            if re.match('__VERSION__\s*=\s*',line) != None:
-                version = line.split('=', 1)[1]
-                return eval(version, {}, {})
-    finally:
-        file.close()
-    raise IOError('Unexpected end-of-file')
-
-__VERSION__=get_version()
+# get the notmuch version number without importing the notmuch module
+version_file = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                            'notmuch', 'version.py')
+execfile(version_file)
+assert __VERSION__, 'Failed to read the notmuch binding version number'
 
 setup(name='notmuch',
       version=__VERSION__,