# HG changeset patch
# User Clark Boylan <clark.boylan@gmail.com>
# Date 1391830704 28800
# Node ID 62fe57a8fd3f8f44be8957e59846387d2f505227
# Parent  b0360a54ab368ef428c7f83601ba6b64f6fec64f
Fix command expansion and parsing.

Tox testenv commands are parsed to expand variable substitutions and
construct the argv list that will be passed to exec. Prior to this
commit this parsing ate quotes surrounding variables and treated
multiword variables as single argv items. Neither behavior was correct.
To fix this create the expanded command before handing it off to shlex
to do the tokenization of the argv list. Doing the parsing in this
order ensures it is correct.

diff --git a/tests/test_config.py b/tests/test_config.py
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -278,7 +278,7 @@
         #    "reader.getargvlist('section', 'key1')")
         assert reader.getargvlist('section', 'key1') == []
         x = reader.getargvlist("section", "key2")
-        assert x == [["cmd1", "with space", "grr"],
+        assert x == [["cmd1", "with", "space", "grr"],
                      ["cmd2", "grr"]]
 
     def test_argvlist_windows_escaping(self, tmpdir, newconfig):
@@ -304,7 +304,7 @@
         #    "reader.getargvlist('section', 'key1')")
         assert reader.getargvlist('section', 'key1') == []
         x = reader.getargvlist("section", "key2")
-        assert x == [["cmd1", "with space", "grr"]]
+        assert x == [["cmd1", "with", "space", "grr"]]
 
 
     def test_argvlist_quoting_in_command(self, tmpdir, newconfig):
diff --git a/tox/_config.py b/tox/_config.py
--- a/tox/_config.py
+++ b/tox/_config.py
@@ -527,30 +527,35 @@
     def _processcommand(self, command):
         posargs = getattr(self, "posargs", None)
 
-        # special treat posargs which might contain multiple arguments
-        # in their defaults
+        # Iterate through each word of the command substituting as
+        # appropriate to construct the new command string. This
+        # string is then broken up into exec argv components using
+        # shlex.
         newcommand = ""
         for word in CommandParser(command).words():
-            if word.startswith("{posargs:") and word.endswith("}"):
+            if word == "{posargs}" or word == "[]":
                 if posargs:
-                    word = "{posargs}"
+                    newcommand += " ".join(posargs)
+                continue
+            elif word.startswith("{posargs:") and word.endswith("}"):
+                if posargs:
+                    newcommand += " ".join(posargs)
+                    continue
                 else:
                     word = word[9:-1]
-            newcommand += word
+            new_arg = ""
+            new_word = self._replace(word)
+            new_word = self._replace(new_word)
+            new_arg += new_word
+            newcommand += new_arg
 
-        # now we can properly parse the command
-        argv = []
-        for arg in shlex.split(newcommand):
-            if arg in ('[]', "{posargs}"):
-                if posargs:
-                    argv.extend(posargs)
-                continue
-            new_arg = ""
-            for word in CommandParser(arg).words():
-                new_word = self._replace(word)
-                new_word = self._replace(new_word)
-                new_arg += new_word
-            argv.append(new_arg)
+        # Construct shlex object that will not escape any values,
+        # use all values as is in argv.
+        shlexer = shlex.shlex(newcommand, posix=True)
+        shlexer.whitespace_split = True
+        shlexer.escape = ''
+        shlexer.commenters = ''
+        argv = list(shlexer)
         return argv
 
     def getargv(self, section, name, default=None, replace=True):