diff --git a/IPython/core/completerlib.py b/IPython/core/completerlib.py
index 850fe33..b03ad5e 100644
--- a/IPython/core/completerlib.py
+++ b/IPython/core/completerlib.py
@@ -20,7 +20,6 @@ import glob
 import inspect
 import os
 import re
-import shlex
 import sys
 
 # Third-party imports
@@ -31,6 +30,7 @@ from zipimport import zipimporter
 from IPython.core.completer import expand_user, compress_user
 from IPython.core.error import TryNext
 from IPython.utils import py3compat
+from IPython.utils._process_common import arg_split
 
 # FIXME: this should be pulled in with the right call via the component system
 from IPython.core.ipapi import get as get_ipython
@@ -56,40 +56,6 @@ magic_run_re = re.compile(r'.*(\.ipy|\.py[w]?)$')
 # Local utilities
 #-----------------------------------------------------------------------------
 
-def shlex_split(x):
-    """Helper function to split lines into segments.
-    """
-    # shlex.split raises an exception if there is a syntax error in sh syntax
-    # for example if no closing " is found. This function keeps dropping the
-    # last character of the line until shlex.split does not raise
-    # an exception. It adds end of the line to the result of shlex.split
-    #
-    # Example:
-    # %run "c:/python -> ['%run','"c:/python']
-
-    # shlex.split has unicode bugs in Python 2, so encode first to str
-    if not py3compat.PY3:
-        x = py3compat.cast_bytes(x)
-
-    endofline = []
-    while x != '':
-        try:
-            comps = shlex.split(x)
-            if len(endofline) >= 1:
-                comps.append(''.join(endofline))
-            if not py3compat.PY3:
-                comps = [py3compat.cast_unicode(x) for x in comps]
-            return comps
-
-        except ValueError:
-            endofline = [x[-1:]]+endofline
-            x = x[:-1]
-
-    x = ''.join(endofline)
-    if not py3compat.PY3:
-        x = py3compat.cast_unicode(x)
-    return [x]
-
 def module_list(path):
     """
     Return the list containing the names of the modules available in the given
@@ -270,7 +236,7 @@ def module_completer(self,event):
 def magic_run_completer(self, event):
     """Complete files that end in .py or .ipy for the %run command.
     """
-    comps = shlex_split(event.line)
+    comps = arg_split(event.line)
     relpath = (len(comps) > 1 and comps[-1] or '').strip("'\"")
 
     #print("\nev=", event)  # dbg
diff --git a/IPython/core/tests/test_completerlib.py b/IPython/core/tests/test_completerlib.py
new file mode 100644
index 0000000..94af88c
--- /dev/null
+++ b/IPython/core/tests/test_completerlib.py
@@ -0,0 +1,61 @@
+# -*- coding: utf-8 -*-
+"""Tests for completerlib.
+
+"""
+from __future__ import absolute_import
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+import os
+import shutil
+import sys
+import tempfile
+import unittest
+from os.path import join
+
+import nose.tools as nt
+from nose import SkipTest
+
+from IPython.core.completerlib import magic_run_completer
+from IPython.testing import decorators as dec
+from IPython.testing import tools as tt
+from IPython.utils import py3compat
+
+
+class MockEvent(object):
+    def __init__(self, line):
+        self.line = line
+
+#-----------------------------------------------------------------------------
+# Test functions begin
+#-----------------------------------------------------------------------------
+class Test_magic_run_completer(unittest.TestCase):
+    def setUp(self):
+        self.BASETESTDIR = tempfile.mkdtemp()
+        for fil in [u"aaå.py", u"a.py", u"b.py"]:
+            with open(join(self.BASETESTDIR, fil), "w") as sfile:
+                sfile.write("pass\n")
+        self.oldpath = os.getcwdu()
+        os.chdir(self.BASETESTDIR)
+
+    def tearDown(self):
+        os.chdir(self.oldpath)
+        shutil.rmtree(self.BASETESTDIR)
+
+    def test_1(self):
+        """Test magic_run_completer, should match two alterntives
+        """
+        event = MockEvent(u"%run a")
+        mockself = None
+        match = magic_run_completer(mockself, event) 
+        self.assertEqual(match, [u"a.py", u"aaå.py",])
+
+    def test_2(self):
+        """Test magic_run_completer, should match one alterntive
+        """
+        event = MockEvent(u"%run aa")
+        mockself = None
+        match = magic_run_completer(mockself, event) 
+        self.assertEqual(match, [u"aaå.py",])