lazy gettext support. Fixes #39

emails/message.py

@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 
 from email.utils import getaddresses, formataddr
 
-from .compat import (string_types, is_callable, to_bytes, formataddr as compat_formataddr)
+from .compat import (string_types, is_callable, to_bytes, formataddr as compat_formataddr, to_unicode)
 from .utils import (SafeMIMEText, SafeMIMEMultipart, sanitize_address,
                     parse_name_and_email, load_email_charsets,
                     encode_header as encode_header_,
@@ -189,6 +189,9 @@ class MessageBuildMixin(object):
             # TODO: may be remove header here ?
             return
 
+        if not isinstance(value, string_types):
+            value = to_unicode(value)
+
         # Prevent header injection
         if '\n' in value or '\r' in value:
             raise BadHeaderError("Header values can't contain newlines (got %r for header %r)" % (value, key))

emails/testsuite/message/test_lazy_gettext.py

@@ -0,0 +1,25 @@
+# encoding: utf-8
+from __future__ import unicode_literals, print_function
+import gettext
+from emails import Message
+from emails.utils import decode_header
+
+def lazy_string(func, string, **variables):
+    from speaklater import make_lazy_string
+    return make_lazy_string(func, string, **variables)
+
+
+def test_lazy_translated():
+    # prepare translations
+    T = gettext.GNUTranslations()
+    T._catalog = {'invitation': 'invitaci\xf3n'}
+    _ = T.gettext
+
+    msg = Message(html='...', subject=lazy_string(_, 'invitation'))
+    assert decode_header(msg.as_message()['subject']) == _('invitation')
+
+    msg = Message(html='...', subject='invitaci\xf3n')
+    assert decode_header(msg.as_message()['subject']) == 'invitaci\xf3n'
+
+
+

requirements/tests-base.txt

@@ -1,4 +1,5 @@
 jinja2
 mako
+speaklater
 pytest
 pytest-cov