Tweak code with suggestions from yesterday.

IPython/config/loader.py

@@ -285,7 +285,8 b' class PyFileConfigLoader(FileConfigLoader):'
             return self.config
 
         namespace = dict(load_subconfig=load_subconfig, get_config=get_config)
-        conf_filename = self.full_filename.encode(sys.getfilesystemencoding())
+        fs_encoding = sys.getfilesystemencoding() or 'ascii'
+        conf_filename = self.full_filename.encode(fs_encoding)
         execfile(conf_filename, namespace)
 
     def _convert_to_config(self):

IPython/core/application.py

@@ -362,6 +362,10 b' class Application(object):'
         This tries to load the config file from disk.  If successful, the
         ``CONFIG_FILE`` config variable is set to the resolved config file
         location.  If not successful, an empty config is used.
+        
+        By default, errors in loading config are handled, and a warning
+        printed on screen. For testing, the suppress_errors option is set
+        to False, so errors will make tests fail.
         """
         self.log.debug("Attempting to load config file: %s" %
                        self.config_file_name)

IPython/core/tests/test_compilerop.py

@@ -16,6 +16,7 b' from __future__ import print_function'
 
 # Stdlib imports
 import linecache
+import sys
 
 # Third-party imports
 import nose.tools as nt
@@ -47,10 +48,12 b' def test_compiler():'
     cp('x=1', 'single')
     nt.assert_true(len(linecache.cache) > ncache)
 
-def test_compiler_unicode():
-    import sys
+def setUp():
+    # Check we're in a proper Python 2 environment (some imports, such
+    # as GTK, can change the default encoding, which can hide bugs.)
     nt.assert_equal(sys.getdefaultencoding(), "ascii")
-    
+
+def test_compiler_unicode():
     cp = compilerop.CachingCompiler()
     ncache = len(linecache.cache)
     cp(u"t = 'žćčšđ'", "single")

IPython/core/tests/test_history.py

@@ -17,8 +17,10 b' import nose.tools as nt'
 from IPython.utils.tempdir import TemporaryDirectory
 from IPython.core.history import HistoryManager, extract_hist_ranges
 
-def test_history():
+def setUp():
     nt.assert_equal(sys.getdefaultencoding(), "ascii")
+
+def test_history():
     ip = get_ipython()
     with TemporaryDirectory() as tmpdir:
         #tmpdir = '/software/temp'

IPython/testing/iptest.py

@@ -168,6 +168,10 b' def make_exclude():'
 
     if not have['wx']:
         exclusions.append(ipjoin('lib', 'inputhookwx'))
+        
+    # We do this unconditionally, so that the test suite doesn't import
+    # gtk, changing the default encoding and masking some unicode bugs.
+    exclusions.append(ipjoin('lib', 'inputhookgtk'))
 
     # These have to be skipped on win32 because the use echo, rm, cd, etc.
     # See ticket https://bugs.launchpad.net/bugs/366982