5 files changed, 12 insertions, 8 deletions
diff --git a/src/zope/i18n/gettextmessagecatalog.py b/src/zope/i18n/gettextmessagecatalog.py
index 7b3985c..307e5be 100644
--- a/src/zope/i18n/gettextmessagecatalog.py
+++ b/src/zope/i18n/gettextmessagecatalog.py
@@ -18,6 +18,7 @@ from gettext import GNUTranslations
 from zope.i18n.interfaces import IGlobalMessageCatalog
 from zope.interface import implementer
 
+
 class _KeyErrorRaisingFallback(object):
     def ugettext(self, message):
         raise KeyError(message)
@@ -32,8 +33,8 @@ class GettextMessageCatalog(object):
 
     def __init__(self, language, domain, path_to_file):
         """Initialize the message catalog"""
-        self.language = language
-        self.domain = domain
+        self.language = language.decode('utf-8') if isinstance(language, bytes) else language
+        self.domain = domain.decode("utf-8") if isinstance(domain, bytes) else domain
         self._path_to_file = path_to_file
         self.reload()
         catalog = self._catalog
diff --git a/src/zope/i18n/simpletranslationdomain.py b/src/zope/i18n/simpletranslationdomain.py
index e131c57..b50fb68 100644
--- a/src/zope/i18n/simpletranslationdomain.py
+++ b/src/zope/i18n/simpletranslationdomain.py
@@ -39,7 +39,7 @@ class SimpleTranslationDomain(object):
 
     def __init__(self, domain, messages=None):
         """Initializes the object. No arguments are needed."""
-        self.domain = domain
+        self.domain = domain.decode("utf-8") if isinstance(domain, bytes) else domain
         self.messages = messages if messages is not None else {}
         assert self.messages is not None
 
diff --git a/src/zope/i18n/tests/test_formats.py b/src/zope/i18n/tests/test_formats.py
index a77fc8e..6d1380d 100644
--- a/src/zope/i18n/tests/test_formats.py
+++ b/src/zope/i18n/tests/test_formats.py
@@ -99,9 +99,9 @@ class LocaleCalendarStub(object):
 
 
 class _TestCase(TestCase):
-    if not hasattr(TestCase, 'assertRaisesRegex'):
-        # Avoid deprecation warnings in Python 3
-        assertRaisesRegex = TestCase.assertRaisesRegexp
+    # Avoid deprecation warnings in Python 3 by making the preferred
+    # method name available for Python 2.
+    assertRaisesRegex = getattr(TestCase, 'assertRaisesRegex', TestCase.assertRaisesRegexp)
 
 
 class TestDateTimePatternParser(_TestCase):
diff --git a/src/zope/i18n/tests/test_imessagecatalog.py b/src/zope/i18n/tests/test_imessagecatalog.py
index 28866e3..2856c67 100644
--- a/src/zope/i18n/tests/test_imessagecatalog.py
+++ b/src/zope/i18n/tests/test_imessagecatalog.py
@@ -16,12 +16,13 @@
 import unittest
 from zope.interface.verify import verifyObject
 from zope.i18n.interfaces import IMessageCatalog
+from zope.schema import getValidationErrors
 
 
 class TestIMessageCatalog(unittest.TestCase):
 
 
-    # This should be overwritten by every class that inherits this test
+    # This should be overridden by every class that inherits this test
     def _getMessageCatalog(self):
         raise NotImplementedError()
 
@@ -34,6 +35,8 @@ class TestIMessageCatalog(unittest.TestCase):
 
     def testInterface(self):
         verifyObject(IMessageCatalog, self._catalog)
+        errors = getValidationErrors(IMessageCatalog, self._catalog)
+        self.assertFalse(errors)
 
     def testGetMessage(self):
         catalog = self._catalog
diff --git a/src/zope/i18n/translationdomain.py b/src/zope/i18n/translationdomain.py
index 274b744..684fa9b 100644
--- a/src/zope/i18n/translationdomain.py
+++ b/src/zope/i18n/translationdomain.py
@@ -38,7 +38,7 @@ text_type = str if bytes is not str else unicode
 class TranslationDomain(object):
 
     def __init__(self, domain, fallbacks=None):
-        self.domain = domain
+        self.domain = domain.decode("utf-8") if isinstance(domain, bytes) else domain
         # _catalogs maps (language, domain) to IMessageCatalog instances
         self._catalogs = {}
         # _data maps IMessageCatalog.getIdentifier() to IMessageCatalog