Use subprocess instead of os.popen

mopidy/__init__.py

@@ -1,30 +1,27 @@
-import os
 import sys
 if not (2, 6) <= sys.version_info < (3,):
     sys.exit(u'Mopidy requires Python >= 2.6, < 3')
 
+from subprocess import PIPE, Popen
+
 VERSION = (0, 4, 0)
 
-def is_in_git_repo():
-    git_dir = os.path.abspath(os.path.join(
-        os.path.dirname(__file__), '../.git'))
-    return os.path.exists(git_dir)
-
 def get_git_version():
-    if not is_in_git_repo():
-        return None
-    git_version = os.popen('git describe').read().strip()
-    if git_version.startswith('v'):
-        git_version = git_version[1:]
-    return git_version
+    process = Popen(['git', 'describe'], stdout=PIPE)
+    if process.wait() != 0:
+        raise Exception|('Execution of "git describe" failed')
+    version = process.stdout.read().strip()
+    if version.startswith('v'):
+        version = version[1:]
+    return version
 
 def get_plain_version():
     return '.'.join(map(str, VERSION))
 
 def get_version():
-    if is_in_git_repo():
+    try:
         return get_git_version()
-    else:
+    except Exception:
         return get_plain_version()
 
 class MopidyException(Exception):