[T3411] FIX: create the billing group when none is selected

recurring_contract/models/recurring_contract.py

@@ -370,9 +370,34 @@ def create(self, vals_list):
                 vals["reference"] = self.env["ir.sequence"].next_by_code(
                     "recurring.contract.ref"
                 )
+            if not vals.get("group_id") and vals.get("partner_id"):
+                vals["group_id"] = self._default_group(vals["partner_id"]).id
         res = super().create(vals_list)
         return res
 
+    def _default_group(self, partner_id):
+        """Billing group to use when none was picked on the contract (T3411).
+
+        Restricted to groups without a payment mode: no collection method was
+        chosen here, so we must not attach the contract to an existing
+        arrangement (LSV, Permanent Order, ...) the sponsor never agreed to.
+        The mode is set later, once it is.
+        """
+        group_model = self.env["recurring.contract.group"]
+        company = self.env.company
+        group = group_model.search(
+            [
+                ("partner_id", "=", partner_id),
+                ("company_id", "=", company.id),
+                ("payment_mode_id", "=", False),
+            ],
+            order="id desc",
+            limit=1,
+        )
+        return group or group_model.create(
+            {"partner_id": partner_id, "company_id": company.id}
+        )
+
     def write(self, vals):
         """Perform various checks when a contract is modified."""
         res = super().write(vals)

recurring_contract/views/recurring_contract_view.xml

@@ -114,6 +114,8 @@
                                 domain="[('partner_id', '=', partner_id)]"
                                 context="{'default_partner_id': partner_id, 'contract_id': id,}"
                                 options="{'no_quick_create': True}"
+                                required="0"
+                                placeholder="Created automatically if left empty"
                             />
                             <field
                                 name="company_id"