bugzilla: add xmlrpcemail submission for Bugzilla 3.6 email interface

bugzilla: add xmlrpcemail submission for Bugzilla 3.6 email interface

Some of the formatting details required for bug submission via email
changed between Bugzilla 3.4 and 3.6. Bugzilla 3.4 requires lines of
the form '@fieldname = value', while 3.6 wants '@fieldname value'.
Also the field @bug_id in 3.4 becomes @id in 3.6.

Bugzilla up to and including 4.0 also recognises the 3.4 format. To save
surprises in the future, check the Bugzilla version and use the 3.6
format from all major versions >= 4. At some point we will
drop support for Bugzilla prior to 3.6 and support the new format only.

--- a/hgext/bugzilla.py	Thu Mar 01 15:27:24 2012 +0000
+++ b/hgext/bugzilla.py	Thu Mar 01 14:50:31 2012 +0000
@@ -612,6 +612,9 @@
                                             'FIXED')
 
         self.bzproxy = xmlrpclib.ServerProxy(bzweb, self.transport(bzweb))
+        ver = self.bzproxy.Bugzilla.version()['version'].split('.')
+        self.bzvermajor = int(ver[0])
+        self.bzverminor = int(ver[1])
         self.bzproxy.User.login(dict(login=user, password=passwd))
 
     def transport(self, uri):
@@ -673,6 +676,13 @@
     But bugs can be marked fixed via email from 3.4 onwards.
     """
 
+    # The email interface changes subtly between 3.4 and 3.6. In 3.4,
+    # in-email fields are specified as '@<fieldname> = <value>'. In
+    # 3.6 this becomes '@<fieldname> <value>'. And fieldname @bug_id
+    # in 3.4 becomes @id in 3.6. 3.6 and 4.0 both maintain backwards
+    # compatibility, but rather than rely on this use the new format for
+    # 4.0 onwards.
+
     def __init__(self, ui):
         bzxmlrpc.__init__(self, ui)
 
@@ -681,6 +691,14 @@
             raise util.Abort(_("configuration 'bzemail' missing"))
         mail.validateconfig(self.ui)
 
+    def makecommandline(self, fieldname, value):
+        if self.bzvermajor >= 4:
+            return "@%s %s" % (fieldname, str(value))
+        else:
+            if fieldname == "id":
+                fieldname = "bug_id"
+            return "@%s = %s" % (fieldname, str(value))
+
     def send_bug_modify_email(self, bugid, commands, comment, committer):
         '''send modification message to Bugzilla bug via email.
 
@@ -701,8 +719,9 @@
                 raise util.Abort(_("default bugzilla user %s email not found") %
                                  user)
         user = matches['users'][0]['email']
+        commands.append(self.makecommandline("id", bugid))
 
-        text = "\n".join(commands) + "\n@bug_id = %d\n\n" % bugid + comment
+        text = "\n".join(commands) + "\n\n" + comment
 
         _charsets = mail._charsets(self.ui)
         user = mail.addressencode(self.ui, user, _charsets)