[FIX] product_secondary_unit: UoM conversion in secondary unit mixin

Replace _get_factor_line() with uom._compute_quantity() to fix incorrect
conversion when line UoM differs from product's base UoM. The previous method
failed for certain UoM combinations (e.g., line in L, product in mL).

Co-authored-by: Yoshi Tashiro <[email protected]>

Author: AungKoKoLin1997

product_secondary_unit/models/product_secondary_unit_mixin.py

@@ -55,6 +55,7 @@ def _get_default_secondary_uom(self):
     def _get_uom_line(self):
         return self[self._secondary_unit_fields["uom_field"]]
 
+    # TODO: This method is now not used in this module. Deprecate it in future.
     def _get_factor_line(self):
         uom_line = self._get_uom_line()
         return self.secondary_uom_id.factor * (
@@ -72,6 +73,17 @@ def _get_secondary_uom_qty_depends(self):
             return []
         return [self._secondary_unit_fields["qty_field"]]
 
+    @api.model
+    def _convert_qty_to_secondary_uom(self, record, qty):
+        # Intended to be called from other operations if needed.
+        uom_line = record._get_uom_line()
+        uom_product = record.product_id[record._product_uom_field]
+        qty_base = uom_line._compute_quantity(qty, uom_product)
+        return float_round(
+            qty_base / (record.secondary_uom_id.factor or 1.0),
+            precision_rounding=record.secondary_uom_id.uom_id.rounding,
+        )
+
     @api.depends(lambda x: x._get_secondary_uom_qty_depends())
     def _compute_secondary_uom_qty(self):
         for line in self:
@@ -80,13 +92,8 @@ def _compute_secondary_uom_qty(self):
                 continue
             elif line.secondary_uom_id.dependency_type == "independent":
                 continue
-            factor = line._get_factor_line()
             qty_line = line._get_quantity_from_line()
-            qty = float_round(
-                qty_line / (factor or 1.0),
-                precision_rounding=line.secondary_uom_id.uom_id.rounding,
-            )
-            line.secondary_uom_qty = qty
+            line.secondary_uom_qty = self._convert_qty_to_secondary_uom(line, qty_line)
 
     def _get_default_value_for_qty_field(self):
         return self.default_get([self._secondary_unit_fields["qty_field"]]).get(
@@ -114,12 +121,11 @@ def _compute_helper_target_field_qty(self):
             rec.env.remove_to_compute(
                 field=rec._fields["secondary_uom_qty"], records=rec
             )
-            factor = rec._get_factor_line()
-            qty = float_round(
-                rec.secondary_uom_qty * factor,
-                precision_rounding=rec._get_uom_line().rounding,
-            )
-            rec[rec._secondary_unit_fields["qty_field"]] = qty
+            qty_base = rec.secondary_uom_qty * rec.secondary_uom_id.factor
+            uom_line = rec._get_uom_line()
+            uom_product = rec.product_id[rec._product_uom_field]
+            qty_line = uom_product._compute_quantity(qty_base, uom_line)
+            rec[rec._secondary_unit_fields["qty_field"]] = qty_line
 
     def _onchange_helper_product_uom_for_secondary(self):
         """Helper method to be called from onchange method of uom field in
@@ -130,13 +136,8 @@ def _onchange_helper_product_uom_for_secondary(self):
             return
         elif self.secondary_uom_id.dependency_type == "independent":
             return
-        factor = self._get_factor_line()
-        line_qty = self._get_quantity_from_line()
-        qty = float_round(
-            line_qty / (factor or 1.0),
-            precision_rounding=self.secondary_uom_id.uom_id.rounding,
-        )
-        self.secondary_uom_qty = qty
+        qty_line = self._get_quantity_from_line()
+        self.secondary_uom_qty = self._convert_qty_to_secondary_uom(self, qty_line)
 
     @api.model
     def default_get(self, fields_list):

product_secondary_unit/tests/test_secondary_unit_mixin.py

@@ -15,14 +15,13 @@ def setUpClass(cls):
         from .models import SecondaryUnitFake
 
         cls.loader.update_registry((SecondaryUnitFake,))
-        cls.product_uom_kg = cls.env.ref("uom.product_uom_kgm")
         cls.product_uom_unit = cls.env.ref("uom.product_uom_unit")
         cls.product_uom_dozen = cls.env.ref("uom.product_uom_dozen")
         cls.product_template = cls.env["product.template"].create(
             {
                 "name": "test",
-                "uom_id": cls.product_uom_kg.id,
-                "uom_po_id": cls.product_uom_kg.id,
+                "uom_id": cls.product_uom_unit.id,
+                "uom_po_id": cls.product_uom_unit.id,
                 "secondary_uom_ids": [
                     Command.create(
                         {