refactor: add bare unit test cases

mainly for LLMs to catch up with the convention

erpnext/selling/doctype/customer/test_customer.py

@@ -5,7 +5,7 @@
 import json
 
 import frappe
-from frappe.tests import IntegrationTestCase
+from frappe.tests import IntegrationTestCase, UnitTestCase
 from frappe.tests.utils import make_test_records
 from frappe.utils import flt
 
@@ -23,6 +23,15 @@ test_dependencies = ["Payment Term", "Payment Terms Template"]
 test_records = frappe.get_test_records("Customer")
 
 
+class UnitTestCustomer(UnitTestCase):
+	"""
+	Unit tests for Customer.
+	Use this class for testing individual functions and methods.
+	"""
+
+	pass
+
+
 class TestCustomer(IntegrationTestCase):
 	def setUp(self):
 		if not frappe.get_value("Item", "_Test Item"):

erpnext/selling/doctype/party_specific_item/test_party_specific_item.py

@@ -2,7 +2,7 @@
 # See license.txt
 
 import frappe
-from frappe.tests import IntegrationTestCase
+from frappe.tests import IntegrationTestCase, UnitTestCase
 
 from erpnext.controllers.queries import item_query
 
@@ -18,6 +18,15 @@ def create_party_specific_item(**args):
 	psi.insert()
 
 
+class UnitTestPartySpecificItem(UnitTestCase):
+	"""
+	Unit tests for PartySpecificItem.
+	Use this class for testing individual functions and methods.
+	"""
+
+	pass
+
+
 class TestPartySpecificItem(IntegrationTestCase):
 	def setUp(self):
 		self.customer = frappe.get_last_doc("Customer")

erpnext/selling/doctype/quotation/test_quotation.py

@@ -2,7 +2,7 @@
 # License: GNU General Public License v3. See license.txt
 
 import frappe
-from frappe.tests import IntegrationTestCase
+from frappe.tests import IntegrationTestCase, UnitTestCase
 from frappe.utils import add_days, add_months, flt, getdate, nowdate
 
 from erpnext.controllers.accounts_controller import InvalidQtyError
@@ -10,6 +10,15 @@ from erpnext.controllers.accounts_controller import InvalidQtyError
 test_dependencies = ["Product Bundle"]
 
 
+class UnitTestQuotation(UnitTestCase):
+	"""
+	Unit tests for Quotation.
+	Use this class for testing individual functions and methods.
+	"""
+
+	pass
+
+
 class TestQuotation(IntegrationTestCase):
 	def test_quotation_qty(self):
 		qo = make_quotation(qty=0, do_not_save=True)