allow getting the language format from the user + only offset datetimes, not dates

email_template_dateutil/email_template.py

@@ -35,16 +35,32 @@ from openerp.addons.email_template import email_template
 
 
 @contextfilter
-def format_date(context, dtstr, new_format, tz=None):
+def format_date(context, dtstr, new_format=None, tz=None):
     if not dtstr:
         return dtstr
 
+    if not new_format:
+        if context.get("user") and context["user"].lang:
+            user = context["user"]
+            lang_obj = user.pool["res.lang"]
+            cr, uid = user._cr, user._uid
+            lang = lang_obj.search(cr, uid, [
+                ('code', '=', user.lang)
+            ])
+            if lang:
+                new_format = lang_obj.browse(cr, uid, lang[0]).date_format
+
+    new_format = new_format or DFMT
+
     try:
         date = datetime.strptime(dtstr, DTFMT)
     except ValueError:
         # Maybe this is a date, not datetime
         date = datetime.strptime(dtstr, DFMT)
-
+    else:
+        # If this was a date, calculating timezones will give unexpected
+        # results. Any timezone with a negative offset will be the day
+        # before, since (midnight - anything) is the previous day
         if tz:
             tz_name = tz
         elif context.get("user") and context["user"].tz: