Attempt with subprocess instead

pre_commit/languages/python.py

@@ -1,5 +1,6 @@
 
 from plumbum import local
+import subprocess
 
 PY_ENV = 'py_env'
 
@@ -7,7 +8,7 @@ PY_ENV = 'py_env'
 def install_environment():
     assert local.path('setup.py').exists()
     # Return immediately if we already have a virtualenv
-    if local.path('py_env').exists():
+    if local.path(PY_ENV).exists():
         return
 
     # Install a virtualenv
@@ -17,6 +18,17 @@ def install_environment():
 
 def run_hook(hook, file_args):
     # TODO: batch filenames
+    process = subprocess.Popen(
+        ['bash', '-c', ' '.join(
+            ['source {0}/bin/activate &&'.format(PY_ENV)] +
+            [hook['entry']] + hook.get('args', []) + list(file_args)
+        )],
+        stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+    )
+    ret = process.communicate()
+
+    return (0,) + ret
+
     return local['bash'][
         '-c', ' '.join(
             ['source {0}/bin/activate &&'.format(PY_ENV)] +