[FIX] mass_mailing: support partner_id field

A sale.order is an authorised model for mass mailing but it does not have
an email or email_from field.
When trying to send a mass mailing campaign on sale orders, an error was raised
as sale_order.email_from does not exists

closes odoo/odoo#30220

addons/mass_mailing/i18n/mass_mailing.pot

@@ -6,8 +6,8 @@ msgid ""
 msgstr ""
 "Project-Id-Version: Odoo Server 12.0\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2019-01-09 10:32+0000\n"
-"PO-Revision-Date: 2019-01-09 10:32+0000\n"
+"POT-Creation-Date: 2019-01-15 10:48+0000\n"
+"PO-Revision-Date: 2019-01-15 10:48+0000\n"
 "Last-Translator: <>\n"
 "Language-Team: \n"
 "MIME-Version: 1.0\n"
@@ -2158,6 +2158,12 @@ msgstr ""
 msgid "Unsubscription Date"
 msgstr ""
 
+#. module: mass_mailing
+#: code:addons/mass_mailing/models/mass_mailing.py:806
+#, python-format
+msgid "Unsupported mass mailing model %r"
+msgstr ""
+
 #. module: mass_mailing
 #. openerp-web
 #: code:addons/mass_mailing/static/src/xml/mass_mailing.xml:17

addons/mass_mailing/models/mass_mailing.py

@@ -798,15 +798,28 @@ class MassMailing(models.Model):
         """Returns a set of emails already targeted by current mailing/campaign (no duplicates)"""
         self.ensure_one()
         target = self.env[self.mailing_model_real]
-        mail_field = 'email' if 'email' in target._fields else 'email_from'
-        # avoid loading a large number of records in memory
-        # + use a basic heuristic for extracting emails
-        query = """
-            SELECT lower(substring(t.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)'))
-              FROM mail_mail_statistics s
-              JOIN %(target)s t ON (s.res_id = t.id)
-             WHERE substring(t.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)') IS NOT NULL
-        """
+        if set(['email', 'email_from']) & set(target._fields):
+            mail_field = 'email' if 'email' in target._fields else 'email_from'
+            # avoid loading a large number of records in memory
+            # + use a basic heuristic for extracting emails
+            query = """
+                SELECT lower(substring(t.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)'))
+                  FROM mail_mail_statistics s
+                  JOIN %(target)s t ON (s.res_id = t.id)
+                 WHERE substring(t.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)') IS NOT NULL
+            """
+        elif 'partner_id' in target._fields:
+            mail_field = 'email'
+            query = """
+                SELECT lower(substring(p.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)'))
+                  FROM mail_mail_statistics s
+                  JOIN %(target)s t ON (s.res_id = t.id)
+                  JOIN res_partner p ON (t.partner_id = p.id)
+                 WHERE substring(p.%(mail_field)s, '([^ ,;<@]+@[^> ,;]+)') IS NOT NULL
+            """
+        else:
+            raise UserError(_("Unsupported mass mailing model %s") % self.mailing_model_id.name)
+
         if self.mass_mailing_campaign_id.unique_ab_testing:
             query +="""
                AND s.mass_mailing_campaign_id = %%(mailing_campaign_id)s;