fix: skip covered rows when ordering from the mrp report (#58249) (#58312)

erpnext/manufacturing/report/material_requirements_planning_report/material_requirements_planning_report.py

@@ -1298,7 +1298,7 @@ def get_item_capacity(item_code, bucket_size):
 
 
 @frappe.whitelist()
-def make_order(selected_rows, company, warehouse=None, mps=None):
+def make_order(selected_rows: str | list, company: str, warehouse: str | None = None, mps: str | None = None):
 	if not frappe.has_permission("Purchase Order", "create"):
 		frappe.throw(_("Not permitted to make Purchase Orders"), frappe.PermissionError)
 
@@ -1308,16 +1308,33 @@ def make_order(selected_rows, company, warehouse=None, mps=None):
 	if not frappe.db.exists("Company", company):
 		frappe.throw(_("Company {0} does not exist").format(company))
 
+	qty_precision = frappe.get_precision("Purchase Order Item", "qty")
 	purchase_orders = {}
 	work_orders = []
+	covered_rows = 0
 	for row in selected_rows:
 		row = frappe._dict(row)
+		# what is left to order once stock and the orders already placed are counted. rounding
+		# to the precision an order is stored in, so what is left of a covered row after all the
+		# subtracting does not become an order line of its own
+		if flt(row.required_qty, qty_precision) <= 0:
+			covered_rows += 1
+			continue
+
 		if row.type_of_material == "Purchase":
 			purchase_orders.setdefault((row.default_supplier, row.release_date), []).append(row)
 
 		if row.type_of_material == "Manufacture" and row.bom_no:
 			work_orders.append(row)
 
+	if not purchase_orders and not work_orders:
+		frappe.msgprint(
+			_("Nothing to order, the selected rows are already covered by stock or existing orders")
+			if covered_rows
+			else _("Nothing to order from the selected rows")
+		)
+		return
+
 	if purchase_orders:
 		make_purchase_orders(purchase_orders, company, warehouse=warehouse, mps=mps)
 

erpnext/manufacturing/report/material_requirements_planning_report/test_material_requirements_planning_report.py

@@ -20,6 +20,7 @@ COMPANY = "_Test Company"
 WAREHOUSE = "_Test Warehouse - _TC"
 SUPPLIER = "_Test Supplier"
 TAX_TEMPLATE = "_Test Purchase Taxes and Charges Template - _TC"
+WIP_WAREHOUSE = "_Test Warehouse 1 - _TC"
 
 
 class TestMaterialRequirementsPlanningReport(ERPNextTestSuite):
@@ -105,6 +106,62 @@ class TestMaterialRequirementsPlanningReport(ERPNextTestSuite):
 		self.assertEqual(work_order.bom_no, plan.bom)
 		self.assertEqual(work_order.qty, plan.planned_qty)
 
+	def test_make_order_skips_rows_that_are_already_covered(self):
+		"""
+		A row whose requirement is met by stock or by an order placed earlier has nothing left
+		to order. It must be left out instead of failing, and the rows beside it must still be
+		created.
+		"""
+		plan = make_mrp_plan(self)
+		covered_row, remaining_rows = plan.rows[0], plan.rows[1:]
+		self.assertTrue(remaining_rows, msg="the plan needs a second row to order")
+		covered_row.required_qty = 0
+
+		make_order(plan.rows, COMPANY, warehouse=WAREHOUSE, mps=plan.mps)
+
+		ordered_items = [
+			row.item_code
+			for doctype in ("Purchase Order", "Work Order")
+			for order in frappe.get_all(doctype, filters={"mps": plan.mps}, pluck="name")
+			for row in get_ordered_items(doctype, order)
+		]
+		self.assertNotIn(covered_row.item_code, ordered_items)
+		self.assertEqual(sorted(ordered_items), sorted([row.item_code for row in remaining_rows]))
+
+	def test_make_order_creates_nothing_when_every_row_is_covered(self):
+		plan = make_mrp_plan(self)
+		for row in plan.rows:
+			row.required_qty = 0
+
+		make_order(plan.rows, COMPANY, warehouse=WAREHOUSE, mps=plan.mps)
+
+		for doctype in ("Purchase Order", "Work Order"):
+			self.assertFalse(frappe.get_all(doctype, filters={"mps": plan.mps}, pluck="name"))
+
+	def test_make_order_ignores_a_requirement_left_over_by_rounding(self):
+		"""What is left of a covered row after subtracting is not a quantity worth ordering."""
+		plan = make_mrp_plan(self)
+		for row in plan.rows:
+			row.required_qty = 0.0000000001
+
+		make_order(plan.rows, COMPANY, warehouse=WAREHOUSE, mps=plan.mps)
+
+		for doctype in ("Purchase Order", "Work Order"):
+			self.assertFalse(frappe.get_all(doctype, filters={"mps": plan.mps}, pluck="name"))
+
+	def test_work_order_keeps_the_company_wip_warehouse(self):
+		"""
+		The item's own warehouse is where the finished goods go, the work in progress warehouse
+		stays the one the company keeps for it.
+		"""
+		plan = make_mrp_plan(self)
+		frappe.db.set_value("Company", COMPANY, "default_wip_warehouse", WIP_WAREHOUSE)
+
+		make_order(plan.rows, COMPANY, warehouse=WAREHOUSE, mps=plan.mps)
+
+		work_order = get_created_order(plan.mps, "Work Order")
+		self.assertEqual(work_order.wip_warehouse, WIP_WAREHOUSE)
+
 	def test_purchase_order_gets_defaults_from_set_missing_values(self):
 		plan = make_mrp_plan(self)
 		make_tax_rule(tax_type="Purchase", purchase_tax_template=TAX_TEMPLATE, priority=1, save=1)
@@ -204,6 +261,14 @@ def make_mrp_plan(test_case, planned_qty=10, rm_qty=2):
 	)
 
 
+def get_ordered_items(doctype, order):
+	child_doctype = "Purchase Order Item" if doctype == "Purchase Order" else None
+	if not child_doctype:
+		return frappe.get_all(doctype, filters={"name": order}, fields=["production_item as item_code"])
+
+	return frappe.get_all(child_doctype, filters={"parent": order}, fields=["item_code"])
+
+
 def get_created_order(mps, doctype):
 	names = frappe.get_all(doctype, filters={"mps": mps}, pluck="name")
 	if len(names) != 1: