fix handling of unicode in KV loader

CaselessStrEnum had to be updated to typecheck basestring instead of str

tests included

IPython/config/loader.py

@@ -379,7 +379,20 b' class KeyValueConfigLoader(CommandLineConfigLoader):'
         super(KeyValueConfigLoader, self).clear()
         self.extra_args = []
         
-
+    
+    def _decode_argv(self, argv, enc=None):
+        """decode argv if bytes, using stin.encoding, falling back on default enc"""
+        uargv = []
+        if enc is None:
+            enc = sys.stdin.encoding or sys.getdefaultencoding()
+        for arg in argv:
+            if not isinstance(arg, unicode):
+                # only decode if not already decoded
+                arg = arg.decode(enc)
+            uargv.append(arg)
+        return uargv
+                
+                
     def load_config(self, argv=None, aliases=None, flags=None):
         """Parse the configuration and generate the Config object.
         
@@ -413,7 +426,7 b' class KeyValueConfigLoader(CommandLineConfigLoader):'
         if flags is None:
             flags = self.flags
         
-        for item in argv:
+        for item in self._decode_argv(argv):
             if kv_pattern.match(item):
                 lhs,rhs = item.split('=',1)
                 # Substitute longnames for aliases.
@@ -427,9 +440,10 b' class KeyValueConfigLoader(CommandLineConfigLoader):'
                     exec exec_str in locals(), globals()
                 except (NameError, SyntaxError):
                     # This case happens if the rhs is a string but without
-                    # the quote marks.  We add the quote marks and see if
+                    # the quote marks. Use repr, to get quote marks, and
+                    # 'u' prefix and see if
                     # it succeeds. If it still fails, we let it raise.
-                    exec_str = 'self.config.' + lhs + '="' + rhs + '"'
+                    exec_str = u'self.config.' + lhs + '=' + repr(rhs)
                     exec exec_str in locals(), globals()
             elif flag_pattern.match(item):
                 # trim leading '--'

IPython/config/tests/test_loader.py

@@ -21,9 +21,12 b' Authors:'
 #-----------------------------------------------------------------------------
 
 import os
+import sys
 from tempfile import mkstemp
 from unittest import TestCase
 
+from nose import SkipTest
+
 from IPython.utils.traitlets import Int, Unicode
 from IPython.config.configurable import Configurable
 from IPython.config.loader import (
@@ -130,6 +133,23 b' class TestKeyValueCL(TestCase):'
         self.assertEquals(cl.extra_args, ['b', 'd'])
         self.assertEquals(config.a, 5)
         self.assertEquals(config.c, 10)
+    
+    def test_unicode_args(self):
+        cl = KeyValueConfigLoader()
+        argv = [u'a=épsîlön']
+        config = cl.load_config(argv)
+        self.assertEquals(config.a, u'épsîlön')
+    
+    def test_unicode_bytes_args(self):
+        uarg = u'a=é'
+        try:
+            barg = uarg.encode(sys.stdin.encoding)
+        except (TypeError, UnicodeEncodeError):
+            raise SkipTest("sys.stdin.encoding can't handle 'é'")
+        
+        cl = KeyValueConfigLoader()
+        config = cl.load_config([barg])
+        self.assertEquals(config.a, u'é')
 
 
 class TestConfig(TestCase):

IPython/utils/traitlets.py

@@ -1099,7 +1099,7 b' class CaselessStrEnum(Enum):'
             if self._allow_none:
                 return value
 
-        if not isinstance(value, str):
+        if not isinstance(value, basestring):
             self.error(obj, value)
 
         for v in self.values: