diff -r 78a3d3700233 Lib/idlelib/config.py
--- a/Lib/idlelib/config.py	Sun Jul 03 19:11:13 2016 -0400
+++ b/Lib/idlelib/config.py	Mon Jul 04 00:04:09 2016 -0400
@@ -20,8 +20,9 @@
 
 import os
 import sys
-
+import idlelib
 from configparser import ConfigParser
+from io import StringIO
 from tkinter.font import Font, nametofont
 
 class InvalidConfigType(Exception): pass
@@ -29,6 +30,8 @@
 class InvalidFgBg(Exception): pass
 class InvalidTheme(Exception): pass
 
+use_userfiles = not idlelib.testing
+
 class IdleConfParser(ConfigParser):
     """
     A ConfigParser specialised for idle configuration file handling
@@ -115,17 +118,24 @@
             self.set(section, option, value)
             return True
 
-    def RemoveFile(self):
-        "Remove user config file self.file from disk if it exists."
-        if os.path.exists(self.file):
-            os.remove(self.file)
+    def reset(self):
+        "Remove sections from userfile for testing."
+        for section in self.sections():
+            self.remove_section(section)
+
+    _load_funcs = {str: ConfigParser.read_string,
+                   dict: ConfigParser.read_dict,
+                   StringIO: ConfigParser.read_file}
+
+    def load(self, source):
+        "Load user options for testing."
+        self._load_funcs[type(source)](self, source)
 
     def Save(self):
         """Update user configuration file.
 
         Remove empty sections. If resulting config isn't empty, write the file
         to disk. If config is empty, remove the file from disk if it exists.
-
         """
         if not self.IsEmpty():
             fname = self.file
@@ -139,6 +149,12 @@
         else:
             self.RemoveFile()
 
+    def RemoveFile(self):
+        "Remove user config file self.file from disk if it exists."
+        if os.path.exists(self.file):
+            os.remove(self.file)
+
+
 class IdleConf:
     """Hold config parsers for all idle config files in singleton instance.
 
@@ -161,24 +177,13 @@
 
     def CreateConfigHandlers(self):
         "Populate default and user config parser dictionaries."
-        #build idle install path
-        if __name__ != '__main__': # we were imported
-            idleDir=os.path.dirname(__file__)
-        else: # we were exec'ed (for testing only)
-            idleDir=os.path.abspath(sys.path[0])
-        userDir=self.GetUserCfgDir()
-
-        defCfgFiles = {}
-        usrCfgFiles = {}
-        # TODO eliminate these temporaries by combining loops
-        for cfgType in self.config_types: #build config file names
-            defCfgFiles[cfgType] = os.path.join(
-                    idleDir, 'config-' + cfgType + '.def')
-            usrCfgFiles[cfgType] = os.path.join(
-                    userDir, 'config-' + cfgType + '.cfg')
-        for cfgType in self.config_types: #create config parsers
-            self.defaultCfg[cfgType] = IdleConfParser(defCfgFiles[cfgType])
-            self.userCfg[cfgType] = IdleUserConfParser(usrCfgFiles[cfgType])
+        idledir = os.path.dirname(__file__)
+        userdir = self.GetUserCfgDir()
+        for cfg_type in self.config_types:
+            self.defaultCfg[cfg_type] = IdleConfParser(
+                os.path.join(idledir, 'config-' + cfg_type + '.def'))
+            self.userCfg[cfg_type] = IdleUserConfParser(
+                os.path.join(userdir, 'config-' + cfg_type + '.cfg'))
 
     def GetUserCfgDir(self):
         """Return a filesystem directory for storing user config files.
@@ -725,7 +730,8 @@
         "Load all configuration files."
         for key in self.defaultCfg:
             self.defaultCfg[key].Load()
-            self.userCfg[key].Load() #same keys
+            if use_userfiles:
+                self.userCfg[key].Load() #same keys
 
     def SaveUserCfgFiles(self):
         "Write all loaded user configuration files to disk."
@@ -735,6 +741,7 @@
 
 idleConf = IdleConf()
 
+
 # TODO Revise test output, write expanded unittest
 #
 if __name__ == '__main__':
diff -r 78a3d3700233 Lib/idlelib/idle_test/test_config.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Lib/idlelib/idle_test/test_config.py	Mon Jul 04 00:04:09 2016 -0400
@@ -0,0 +1,33 @@
+"""Unittests for idlelib.config_help.py"""
+import unittest
+
+#import idlelib
+#idlelib.testing = True
+# As long as idlelib.run imports something that imports config,
+# above does not work for individual file run from IDLE.
+# Instead, after config import, reset each user cfg, in setUpModule.
+
+def setUpModule():
+    global config, idleconf
+    from idlelib import config
+    config.use_userfiles = False
+    idleconf = config.idleConf
+    for cfg in idleconf.config_types:
+        idleconf.userCfg[cfg].reset()
+
+def tearDownModule():
+    config.use_userfiles = True
+
+
+class UserLoadTest(unittest.TestCase):
+
+    def test_user_load(self):
+        usermain = idleconf.userCfg['main']
+        self.assertTrue(not usermain.sections())
+        usermain.load('[General]\nautosave=2')
+        self.assertEqual(usermain['General']['autosave'],'2')
+        usermain.remove_section('General')
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2, exit=False)