fix(stock): update variant attributes on value rename

erpnext/controllers/item_variant.py

@@ -7,6 +7,7 @@ import json
 
 import frappe
 from frappe import _
+from frappe.query_builder import Case
 from frappe.utils import cstr, flt
 
 from erpnext.utilities.product import get_item_codes_by_attributes
@@ -156,18 +157,22 @@ def update_variant_attribute_values(item_attribute):
 
 	item_variant_table = frappe.qb.DocType("Item Variant Attribute")
 	item_table = frappe.qb.DocType("Item")
+	attribute_value = item_variant_table.attribute_value
+	attribute_value_case = Case()
 
 	for old_value, new_value in value_map.items():
-		(
+		attribute_value_case = attribute_value_case.when(attribute_value == old_value, new_value)
-			frappe.qb.update(item_variant_table)
+
-			.join(item_table)
+	(
-			.on(item_table.name == item_variant_table.parent)
+		frappe.qb.update(item_variant_table)
-			.set(item_variant_table.attribute_value, new_value)
+		.join(item_table)
-			.where(item_table.variant_of.isnotnull())
+		.on(item_table.name == item_variant_table.parent)
-			.where(item_table.variant_of != "")
+		.set(attribute_value, attribute_value_case.else_(attribute_value))
-			.where(item_variant_table.attribute == item_attribute.name)
+		.where(item_table.variant_of.isnotnull())
-			.where(item_variant_table.attribute_value == old_value)
+		.where(item_table.variant_of != "")
-		).run()
+		.where(item_variant_table.attribute == item_attribute.name)
+		.where(attribute_value.isin(list(value_map)))
+	).run()
 
 	frappe.flags.attribute_values = None
 

erpnext/stock/doctype/item/test_item.py

@@ -395,6 +395,54 @@ class TestItem(FrappeTestCase):
 			"Larger",
 		)
 
+	def test_swapped_attribute_value_renames_update_variants(self):
+		frappe.delete_doc_if_exists("Item", "_Test Variant Item-L", force=1)
+		frappe.delete_doc_if_exists("Item", "_Test Variant Item-S", force=1)
+
+		large_variant = create_variant("_Test Variant Item", {"Test Size": "Large"})
+		large_variant.save()
+
+		small_variant = create_variant("_Test Variant Item", {"Test Size": "Small"})
+		small_variant.save()
+
+		attribute = frappe.get_doc("Item Attribute", "Test Size")
+		original_values = {row.name: row.attribute_value for row in attribute.item_attribute_values}
+
+		def restore_test_size_values():
+			doc = frappe.get_doc("Item Attribute", "Test Size")
+			for row in doc.item_attribute_values:
+				row.attribute_value = original_values[row.name]
+			frappe.flags.attribute_values = None
+			doc.save()
+
+		self.addCleanup(restore_test_size_values)
+
+		for row in attribute.item_attribute_values:
+			if row.attribute_value == "Large":
+				row.attribute_value = "Small"
+			elif row.attribute_value == "Small":
+				row.attribute_value = "Large"
+
+		frappe.flags.attribute_values = None
+		attribute.save()
+
+		self.assertEqual(
+			frappe.db.get_value(
+				"Item Variant Attribute",
+				{"parent": large_variant.name, "attribute": "Test Size"},
+				"attribute_value",
+			),
+			"Small",
+		)
+		self.assertEqual(
+			frappe.db.get_value(
+				"Item Variant Attribute",
+				{"parent": small_variant.name, "attribute": "Test Size"},
+				"attribute_value",
+			),
+			"Large",
+		)
+
 	def test_make_item_variant(self):
 		frappe.delete_doc_if_exists("Item", "_Test Variant Item-L", force=1)