Use a full unicode layer in preferences.py

CHANGES.txt

@@ -8,7 +8,7 @@ Enhancements
 
 * Apptools now have a changelog!
 * Preferences system defaults to utf-8 encoded string with ConfigObj providing
-  better support for unicode in the PreferenceHelper (#41).
+  better support for unicode in the PreferenceHelper (#41, #45).
 * Added a traitsified backport of Python 3's lru_cache (#39).
 * Added PyTables support to the io submodule (#19, #20, and #24 through #34).
 * Added a SelectionService for managing selections within an application (#15, #16, #17,

apptools/preferences/preferences.py

@@ -541,6 +541,11 @@ def _remove_preferences_listener(self, listener):
 
     def _set(self, key, value):
         """ Set the value of a preference in this node. """
+
+        # everything must be unicode encoded so that ConfigObj configuration
+        # can properly serialize the data. Python str are supposed to be ASCII
+        # encoded.
+        value = unicode(value)
 
         self._lk.acquire()
         old = self._preferences.get(key)

apptools/preferences/preferences_helper.py

@@ -128,15 +128,10 @@ def _get_value(self, trait_name, value):
         trait = self.trait(trait_name)
         handler = trait.handler
 
-        # If the trait type is 'Str' then we just take the raw value.
-        if isinstance(handler, Str) or trait.is_str:
+        # If the trait type is 'Str' or Unicode then we just take the raw value.
+        if isinstance(handler, (Str, Unicode)) or trait.is_str:
             pass
 
-        elif isinstance(handler, Unicode):
-            # Just in case we get back an ASCII `str` object, convert it to a
-            # `unicode` object.     
-            value = unicode(value) 
-
         # Otherwise, we eval it!
         else:
             try:

apptools/preferences/tests/preferences_helper_test_case.py

@@ -201,7 +201,7 @@ class AcmeUIPreferencesHelper(PreferencesHelper):
         return
 
     def test_real_unicode_values(self):
-        """ default values """
+        """ Test with real life unicode values """
 
         p = self.preferences
         p.load(self.example)
@@ -217,25 +217,30 @@ class AcmeUIPreferencesHelper(PreferencesHelper):
             width       = Int(50)
             ratio       = Float(1.0)
             visible     = Bool(True)
-            description = Unicode(u'U\xdc\xf2ser')
+            description = Unicode(u'')
             offsets     = List(Int, [1, 2, 3, 4])
             names       = List(Str, ['joe', 'fred', 'jane'])
 
         helper = AcmeUIPreferencesHelper()
 
+        first_unicode_str = u'U\xdc\xf2ser'
+        first_utf8_str = 'U\xc3\x9c\xc3\xb2ser'
+
         original_description = helper.description
-        helper.description = u'U\xdc\xf2ser'
-        self.assertEqual(u'U\xdc\xf2ser', helper.description)
+        helper.description = first_unicode_str
+        self.assertEqual(first_unicode_str, helper.description)
 
 
-        helper.description = u'caf\xe9'
-        self.assertEqual(u'caf\xe9', helper.description)
-        self.assertEqual(u'caf\xe9', p.get('acme.ui.description'))
+        second_unicode_str = u'caf\xe9'
+        second_utf8_str = 'caf\xc3\xa9'
+        helper.description = second_unicode_str
+        self.assertEqual(second_unicode_str, helper.description)
+        self.assertEqual(second_unicode_str, p.get('acme.ui.description'))
 
         p.save(self.example)
 
         p.load(self.example)
-        self.assertEqual(u'caf\xe9', p.get('acme.ui.description'))
+        self.assertEqual(second_unicode_str, p.get('acme.ui.description'))
         self.assertEqual(u'True', p.get('acme.ui.visible'))
         self.assertEqual(True, helper.visible)
 
@@ -496,11 +501,11 @@ def _width_changed(self, trait_name, old, new):
         # ratio to get set via the static trait change handler on the helper.
         p.set('acme.ui.width', 42)
         self.assertEqual(42, helper.width)
-        self.assertEqual(42, p.get('acme.ui.width'))
+        self.assertEqual('42', p.get('acme.ui.width'))
 
         # Did the ratio get changed?
         self.assertEqual(3.0, helper.ratio)
-        self.assertEqual(3.0, p.get('acme.ui.ratio'))
+        self.assertEqual('3.0', p.get('acme.ui.ratio'))
 
         return