dash_e: fixes #109 and #111

Behaviour of -e has not changed, but can be set by passing True or False
as a parameter multi_dash_e to tox/_config.py: prepare_parse()

This parameter should come from a user specifyable default value
for backwards compatibility. Default should preferable be True after
that is implemented.

_split_env() was factored out of class parseini to enable testing

The issue #111: error on specifying same env twice ("tox -e py27,py27")
fixed. Multiple specifications of the same environment result in
multiple invocation (this could also be selectable in a
configuration file)

2 files changed, 11 insertions, 38 deletions

diff --git a/tests/test_config.py b/tests/test_config.py
index 6870af1..029bf11 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -931,34 +931,26 @@ class TestCmdInvocation:
 
 class TestArgumentParser:
 
-    def test_dash_e_silent1(self):
-        parser = prepare_parse('testpkg', None)
-        args = parser.parse_args('-e py26 -e py33'.split())
+    def test_dash_e_single_1(self):
+        parser = prepare_parse('testpkg')
+        args = parser.parse_args('-e py26'.split())
         envlist = _split_env(args.env)
-        assert envlist == ['py33']
+        assert envlist == ['py26']
 
-    def test_dash_e_silent2(self):
-        parser = prepare_parse('testpkg', None)
+    def test_dash_e_single_2(self):
+        parser = prepare_parse('testpkg')
         args = parser.parse_args('-e py26,py33'.split())
         envlist = _split_env(args.env)
         assert envlist == ['py26', 'py33']
 
-    def test_dash_e_silent3(self):
-        parser = prepare_parse('testpkg', None)
+    def test_dash_e_same(self):
+        parser = prepare_parse('testpkg')
         args = parser.parse_args('-e py26,py26'.split())
         envlist = _split_env(args.env)
         assert envlist == ['py26', 'py26']
 
-    def test_dash_e_warn(self, capsys):
-        parser = prepare_parse('testpkg', False)
-        args = parser.parse_args('-e py26,py32 -e py33'.split())
-        envlist = _split_env(args.env)
-        out, err = capsys.readouterr()
-        assert 'WARNING: previous optional argument "-e py26' in out
-        assert envlist == ['py33']
-
     def test_dash_e_combine(self):
-        parser = prepare_parse('testpkg', True)
+        parser = prepare_parse('testpkg')
         args = parser.parse_args('-e py26,py25,py33 -e py33,py27'.split())
         envlist = _split_env(args.env)
         assert envlist == ['py26', 'py25', 'py33', 'py33', 'py27']
diff --git a/tox/_config.py b/tox/_config.py
index 16cd288..6b4862f 100644
--- a/tox/_config.py
+++ b/tox/_config.py
@@ -66,18 +66,7 @@ class CountAction(argparse.Action):
         else:
             setattr(namespace, self.dest, 0)
 
-class CheckSingleStoreAction(argparse.Action):
-    """issue a warning when the store action is called multiple times"""
-    def __call__(self, parser, namespace, values, option_string=None):
-        if getattr(namespace, self.dest, None) is not None:
-            py.builtin.print_(
-                'WARNING: previous optional argument "' + option_string + " " +
-                getattr(namespace, self.dest) + '" overwritten by "' +
-                option_string + " " + values + '"')
-        setattr(namespace, self.dest, values)
-
-
-def prepare_parse(pkgname, multi_dash_e=None):
+def prepare_parse(pkgname):
     """setup ArgumentParser
 
     multi_dash_e:
@@ -101,13 +90,7 @@ def prepare_parse(pkgname, multi_dash_e=None):
     parser.add_argument("-c", action="store", default="tox.ini",
         dest="configfile",
         help="use the specified config file name.")
-    if multi_dash_e is None:
-        dash_e_action = "store"
-    elif multi_dash_e is False:
-        dash_e_action = CheckSingleStoreAction
-    elif multi_dash_e is True:
-        dash_e_action = "append"
-    parser.add_argument("-e", action=dash_e_action, dest="env",
+    parser.add_argument("-e", action="append", dest="env",
         metavar="envlist",
         help="work against specified environments (ALL selects all).")
     parser.add_argument("--notest", action="store_true", dest="notest",
@@ -376,8 +359,6 @@ class parseini:
 def _split_env(env):
     """if handed a list, action="append" was used for -e """
     envlist = []
-    if not isinstance(env, list):
-        env = [env]
     for to_split in env:
         for single_env in to_split.split(","):
             # "remove True or", if not allowing multiple same runs, update tests