Fixes for argcomplete

- separate out most argcomplete related stuff in new file _argcomplete.py
  (could probably be in the py library)
- allow positional arguments to be interspaced with optional arguments
  ( + test in test_parseopt.py )
- removed double argument in tox.ini
- add documentation on installing argcomplete (>=0.5.7 as needed for
  Python 3), might need improving/incorporation in index.

This does not work on 2.5 yet. I have patches for argcomplete
(with/print()/"".format) but I am not sure they will be accepted.
Agreed with hpk not to push for that.

Removing argcomplete and leaving completion code active now works by early
exit, so <TAB> no longer re-runs the programs without parameters
(which took long for py.test)

test calls bash with a script that redirects filedescriptor 8 (as used by
argcomplete), so the result can be tested.

--HG--
branch : argcomplete

testing/test_parseopt.py

@@ -130,6 +130,21 @@ class TestParser:
         args = parser.parse(['--ultimate-answer', '42'])
         assert args.ultimate_answer == 42
 
+    def test_parse_split_positional_arguments(self):
+        parser = parseopt.Parser()
+        parser.addoption("-R", action='store_true')
+        parser.addoption("-S", action='store_false')
+        args = parser.parse(['-R', '4', '2', '-S'])
+        assert getattr(args, parseopt.Config._file_or_dir) == ['4', '2']
+        args = parser.parse(['-R', '-S', '4', '2', '-R'])
+        assert getattr(args, parseopt.Config._file_or_dir) == ['4', '2']
+        assert args.R == True
+        assert args.S == False
+        args = parser.parse(['-R', '4', '-S', '2'])
+        assert getattr(args, parseopt.Config._file_or_dir) == ['4', '2']
+        assert args.R == True
+        assert args.S == False
+
     def test_parse_defaultgetter(self):
         def defaultget(option):
             if not hasattr(option, 'type'):
@@ -158,3 +173,28 @@ def test_addoption_parser_epilog(testdir):
     #assert result.ret != 0
     result.stdout.fnmatch_lines(["hint: hello world", "hint: from me too"])
 
+@pytest.mark.skipif("sys.version_info < (2,5)")
+def test_argcomplete(testdir):
+    import os
+    p = py.path.local.make_numbered_dir(prefix="test_argcomplete-",
+                keep=None, rootdir=testdir.tmpdir)
+    script = p._fastjoin('test_argcomplete')
+    with open(str(script), 'w') as fp:
+        # redirect output from argcomplete to stdin and stderr is not trivial
+        # http://stackoverflow.com/q/12589419/1307905
+        # so we use bash
+        fp.write('COMP_WORDBREAKS="$COMP_WORDBREAKS" $(which py.test) '
+                 '8>&1 9>&2')
+    os.environ['_ARGCOMPLETE'] = "1"
+    os.environ['_ARGCOMPLETE_IFS'] =  "\x0b"
+    os.environ['COMP_LINE'] = "py.test --fu"
+    os.environ['COMP_POINT'] = "12"
+    os.environ['COMP_WORDBREAKS'] = ' \\t\\n"\\\'><=;|&(:'
+
+    result = testdir.run('bash', str(script), '--fu')
+    print dir(result), result.ret
+    if result.ret == 255:
+        # argcomplete not found
+        assert True
+    else:
+        result.stdout.fnmatch_lines(["--funcargs", "--fulltrace"])