Fix argument parsing in python 2.7.9

[Changaco]

With python 2.7.9 honcho doesn't read the env files provided via the -e command line argument, because of a change in the argparse module.

[Changaco]

The change in the argparse module:

--- argparse-2.7.8.py   2014-12-18 18:44:37.956126224 +0100
+++ argparse-2.7.9.py   2014-12-18 18:44:23.426106089 +0100
@@ -1089,7 +1089,14 @@
         # parse all the remaining options into the namespace
         # store any unrecognized options on the object, so that the top
         # level parser can decide what to do with them
-        namespace, arg_strings = parser.parse_known_args(arg_strings, namespace)
+
+        # In case this subparser defines new defaults, we parse them
+        # in a new namespace object and then update the original
+        # namespace for the relevant parts.
+        subnamespace, arg_strings = parser.parse_known_args(arg_strings, None)
+        for key, value in vars(subnamespace).items():
+            setattr(namespace, key, value)
+
         if arg_strings:
             vars(namespace).setdefault(_UNRECOGNIZED_ARGS_ATTR, [])
             getattr(namespace, _UNRECOGNIZED_ARGS_ATTR).extend(arg_strings)

[slafs]

Thanks for bringing this up.
I've restarted our latest master build on Travis-CI and yeah... now the build on python 2.7.9 is failing.

I'm not very familiar with argparse to be honest, but it seems that your PR fixes those tests that are broken on 2.7.9 now. Although it introduced some problems with test_export.py

[Changaco]

I've found a backward-compatible way of fixing the problem, tests are now passing.

[slafs]

Thanks but now I think it's even more broken than before. A simple honcho --help gives me

usage: honcho [-e ENV] [-d APP_ROOT] [-f PROCFILE] [-v]
              {check,export,help,run,start,version} ...
honcho: error: too few arguments

on both python 2.7 (including 2.7.9) and 3.4.

I will have to take a closer look on this I guess.

[Changaco]

Problem fixed by removing add_help=False.

[nickstenning]

Thank you for your help. I've reworked this slightly and committed it as 1319da7. It's now released as v0.6.4.

[ecdsa]

Thank you for your help. I have had a related issue in electrum.
As a workaround, I reverted the last change to argparse._SubParsersAction.__call__
see spesmilo/electrum@1d1d76b