[19.0][FIX] ddmrp: drop the unreachable product-UoM-change buffer guard

ddmrp/models/product_template.py

@@ -1,8 +1,7 @@
 # Copyright 2019-20 ForgeFlow S.L. (http://www.forgeflow.com)
 # License LGPL-3.0 or later (https://www.gnu.org/licenses/lgpl.html).
 
-from odoo import api, fields, models
-from odoo.exceptions import ValidationError
+from odoo import fields, models
 
 
 class ProductTemplate(models.Model):
@@ -16,29 +15,5 @@ def _compute_buffer_count(self):
                 variant.buffer_count for variant in rec.product_variant_ids
             )
 
-    # UOM: (stock_orderpoint_uom):
-    @api.constrains("uom_id")
-    def _check_buffer_procure_uom(self):
-        for rec in self:
-            buffers = self.env["stock.buffer"].search(
-                [
-                    ("product_id", "in", rec.product_variant_ids.ids),
-                ],
-            )
-            uom_id = rec.uom_id
-            incompatible = buffers.filtered(
-                lambda b, uom_id=uom_id: b.procure_uom_id
-                and not b.procure_uom_id._compute_quantity(
-                    1.0, uom_id, raise_if_failure=False
-                )
-            )
-            if incompatible:
-                raise ValidationError(
-                    rec.env._(
-                        "At least one stock buffer for this product has a "
-                        "different Procurement unit of measure category."
-                    )
-                )
-
     def action_view_stock_buffers(self):
         return self.product_variant_ids.action_view_stock_buffers()

ddmrp/tests/test_ddmrp.py

@@ -1569,3 +1569,31 @@ def test_55_purchase_line_form_no_newid_domain_warning(self):
             with po_form.order_line.new() as line:
                 line.product_id = self.product_purchased
         po_form.save()
+
+    def test_53_procure_uom_follows_product_uom_change(self):
+        """Changing a product UoM resets the buffers' procurement UoM.
+
+        _compute_procure_uom_id re-derives procure_uom_id from the product
+        UoM whenever it changes, so buffers can never be left with a
+        procurement UoM incompatible with the new product UoM.
+        """
+        product = self.productModel.create(
+            {
+                "name": "Product UoM follow",
+                "is_storable": True,
+                "uom_id": self.uom_unit.id,
+            }
+        )
+        buffer = self.bufferModel.create(
+            {
+                "buffer_profile_id": self.buffer_profile_pur.id,
+                "product_id": product.id,
+                "warehouse_id": self.warehouse.id,
+                "location_id": self.stock_location.id,
+                "adu_calculation_method": self.adu_fixed.id,
+                "procure_uom_id": self.dozen_unit.id,
+            }
+        )
+        meter = self.env.ref("uom.product_uom_meter")
+        product.product_tmpl_id.uom_id = meter
+        self.assertEqual(buffer.procure_uom_id, meter)