Prevent attribute error when trying to decode none value

CHANGELOG.rst

@@ -1,6 +1,15 @@
 Changelog
 =========
 
+Upcoming release
+----------------
+
+- Prevent ``AttributeError`` when trying to humanize ``None`` value (`#6`_),
+  thanks to `@earlbread`_ for the report.
+
+.. _#6: https://github.com/vitalk/flask-humanize/pull/6
+.. _@earlbread: https://github.com/earlbread
+
 0.3.0 (2016-03-26)
 ------------------
 

flask_humanize/__init__.py

@@ -16,15 +16,18 @@
 from flask import current_app
 from werkzeug.datastructures import ImmutableDict
 
-from . import compat
+from .compat import (
+    text_type, string_types
+)
 
 
 __version__ = '0.3.0'
 
 
 def force_unicode(value):
-    if not isinstance(value, compat.text_type):
-        return value.decode('utf-8')
+    if isinstance(value, string_types):
+        if not isinstance(value, text_type):
+            return value.decode('utf-8')
     return value
 
 

flask_humanize/compat.py

@@ -7,5 +7,7 @@
 
 if PY2:
     text_type = unicode
+    string_types = basestring,
 else:
     text_type = str
+    string_types = str,

tests/test_humanize.py

@@ -43,6 +43,9 @@ def test_defaults(self, config, h):
 @pytest.mark.usefixtures('app')
 class TestHumanize:
 
+    def test_none(self, h):
+        assert h._humanize(None) is None
+
     def test_naturalday(self, h):
         assert h._humanize(today, 'naturalday') == 'today'
         assert h._humanize(today + one_day, 'naturalday') == 'tomorrow'