add merge funcions for units (#1146)

mealie/repos/repository_units.py

@@ -0,0 +1,32 @@
+from pydantic import UUID4
+
+from mealie.db.models.recipe.ingredient import IngredientUnitModel
+from mealie.schema.recipe.recipe_ingredient import IngredientUnit
+
+from .repository_generic import RepositoryGeneric
+
+
+class RepositoryUnit(RepositoryGeneric[IngredientUnit, IngredientUnitModel]):
+    def merge(self, from_unit: UUID4, to_unit: UUID4) -> IngredientUnit | None:
+
+        from_model: IngredientUnitModel = (
+            self.session.query(self.sql_model).filter_by(**self._filter_builder(**{"id": from_unit})).one()
+        )
+
+        to_model: IngredientUnitModel = (
+            self.session.query(self.sql_model).filter_by(**self._filter_builder(**{"id": to_unit})).one()
+        )
+
+        to_model.ingredients += from_model.ingredients
+
+        try:
+            self.session.delete(from_model)
+            self.session.commit()
+        except Exception as e:
+            self.session.rollback()
+            raise e
+
+        return self.get_one(to_unit)
+
+    def by_group(self, group_id: UUID4) -> "RepositoryUnit":
+        return super().by_group(group_id)  # type: ignore