Moved smart_unicode and StrAndUnicode to django.utils.encoding. They are useful

outside of newforms. This is backwards compatible as far as smart_unicode goes
(since newforms.util still imports it). All imports of smart_unicode and
StrAndUnicode have also been updated.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@4918 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/utils/encoding.py

@@ -0,0 +1,28 @@
+from django.conf import settings
+from django.utils.functional import Promise
+
+def smart_unicode(s):
+    if isinstance(s, Promise):
+        # The input is the result of a gettext_lazy() call, or similar. It will
+        # already be encoded in DEFAULT_CHARSET on evaluation and we don't want
+        # to evaluate it until render time.
+        return s
+    if not isinstance(s, basestring,):
+        if hasattr(s, '__unicode__'):
+            s = unicode(s)
+        else:
+            s = unicode(str(s), settings.DEFAULT_CHARSET)
+    elif not isinstance(s, unicode):
+        s = unicode(s, settings.DEFAULT_CHARSET)
+    return s
+
+class StrAndUnicode(object):
+    """
+    A class whose __str__ returns its __unicode__ as a bytestring
+    according to settings.DEFAULT_CHARSET.
+
+    Useful as a mix-in.
+    """
+    def __str__(self):
+        return self.__unicode__().encode(settings.DEFAULT_CHARSET)
+