Fix install problems related to the __version__ variable

Author: slarse

repomate_plug/__init__.py

@@ -1,14 +1,13 @@
 import pluggy
 
+from repomate_plug.__version import __version__
 from repomate_plug.pluginmeta import Plugin
 from repomate_plug.util import hookimpl as repomate_hook
 from repomate_plug.util import HookResult
 from repomate_plug.util import Status
 from repomate_plug.corehooks import PeerReviewHook as _peer_hook
 from repomate_plug.exthooks import CloneHook as _clone_hook
 
-__version__ = '0.4.0'
-
 manager = pluggy.PluginManager(__package__)
 manager.add_hookspecs(_clone_hook)
 manager.add_hookspecs(_peer_hook)

repomate_plug/__version.py

@@ -0,0 +1 @@
+__version__ = '0.4.0'

setup.py

@@ -1,9 +1,15 @@
+import re
 from setuptools import setup, find_packages
-from repomate_plug import __version__
 
 with open('README.md', mode='r', encoding='utf-8') as f:
     readme = f.read()
 
+# parse the version instead of importing it to avoid dependency-related crashes
+with open('repomate_plug/__version.py', mode='r', encoding='utf-8') as f:
+    line = f.readline()
+    __version__ = line.split('=')[1].strip(" '\"")
+    assert re.match(r'\d\.\d\.\d', __version__)
+
 test_requirements = ['pytest', 'pytest-cov', 'codecov']
 required = ['pluggy']