fix: ensure tax withholding entries respect date range of category

(cherry picked from commit 9ead8d4e3f)

erpnext/accounts/doctype/tax_withholding_category/test_tax_withholding_category.py

@@ -5,8 +5,7 @@ import datetime
 from unittest.mock import patch
 
 import frappe
-from frappe.custom.doctype.custom_field.custom_field import create_custom_fields
+from frappe.utils import add_days, add_months, getdate, today
-from frappe.utils import add_days, add_months, today
 
 from erpnext.accounts.doctype.payment_entry.payment_entry import get_payment_entry
 from erpnext.accounts.utils import get_fiscal_year
@@ -1922,7 +1921,6 @@ class TestTaxWithholdingCategory(ERPNextTestSuite):
 
 	def set_previous_fy_and_tax_category(self):
 		test_company = "_Test Company"
-		category = "Cumulative Threshold TDS"
 
 		def add_company_to_fy(fy, company):
 			if not [x.company for x in fy.companies if x.company == company]:
@@ -1948,20 +1946,6 @@ class TestTaxWithholdingCategory(ERPNextTestSuite):
 			)
 			self.prev_fy.save()
 
-		# setup tax withholding category for previous fiscal year
-		cat = frappe.get_doc("Tax Withholding Category", category)
-		cat.append(
-			"rates",
-			{
-				"from_date": self.prev_fy.year_start_date,
-				"to_date": self.prev_fy.year_end_date,
-				"tax_withholding_rate": 10,
-				"single_threshold": 0,
-				"cumulative_threshold": 30000,
-			},
-		)
-		cat.save()
-
 	def test_tds_across_fiscal_year(self):
 		"""
 		Advance TDS on previous fiscal year should be properly allocated on Invoices in upcoming fiscal year
@@ -1972,6 +1956,14 @@ class TestTaxWithholdingCategory(ERPNextTestSuite):
 		supplier = "Test TDS Supplier"
 		# Cumulative threshold 30000 and tax rate 10%
 		category = "Cumulative Threshold TDS"
+		create_tax_withholding_category(
+			category_name=category,
+			rate=10,
+			from_date=self.prev_fy.year_start_date,
+			to_date=self.prev_fy.year_end_date,
+			account="TDS - _TC",
+			cumulative_threshold=30000,
+		)
 		frappe.db.set_value(
 			"Supplier",
 			supplier,
@@ -2043,6 +2035,158 @@ class TestTaxWithholdingCategory(ERPNextTestSuite):
 		self.assertEqual(pi2.taxes, [])
 		self.assertEqual(payment.taxes[0].tax_amount, 6000)
 
+	def test_threshold_resets_in_new_fiscal_year(self):
+		"""
+		Threshold entries from a previous FY must not carry over into the new FY.
+		"""
+		self.set_previous_fy_and_tax_category()
+		invoices = []
+		supplier = "Test TDS Supplier"
+		category = "Cumulative Threshold TDS"
+		create_tax_withholding_category(
+			category_name=category,
+			rate=10,
+			from_date=self.prev_fy.year_start_date,
+			to_date=self.prev_fy.year_end_date,
+			account="TDS - _TC",
+			cumulative_threshold=30000,
+		)
+		self.setup_party_with_category("Supplier", supplier, category)
+		prev_fy_date = add_days(self.prev_fy.year_end_date, -10)
+
+		# Previous FY: 3 invoices to cross the 30000 cumulative threshold
+		for _ in range(3):
+			pi = create_purchase_invoice(supplier=supplier, posting_date=prev_fy_date, set_posting_time=True)
+			pi.submit()
+			invoices.append(pi)
+
+		# Third invoice crosses the threshold - 3000 TDS deducted across all three
+		self.validate_tax_deduction(invoices[-1], 3000)
+
+		# Current FY: 10000 invoice - must be Under Withheld, threshold resets
+		pi_curr = create_purchase_invoice(supplier=supplier)
+		pi_curr.submit()
+		invoices.append(pi_curr)
+		self.validate_tax_deduction(pi_curr, 0)
+
+		self.validate_tax_withholding_entries(
+			"Purchase Invoice",
+			pi_curr.name,
+			[
+				self.get_tax_withholding_entry(
+					tax_withholding_category=category,
+					party_type="Supplier",
+					party=supplier,
+					taxable_doctype="Purchase Invoice",
+					taxable_name=pi_curr.name,
+					tax_rate=10.0,
+					taxable_amount=10000.0,
+					withholding_amount=0.0,
+					status="Under Withheld",
+					withholding_doctype=None,
+					withholding_name=None,
+					under_withheld_reason=None,
+				)
+			],
+		)
+		self.cleanup_invoices(invoices)
+
+	def test_tax_on_excess_threshold_resets_in_new_fiscal_year(self):
+		"""
+		For tax-on-excess categories, unused threshold must reset each FY.
+		"""
+		self.set_previous_fy_and_tax_category()
+		invoices = []
+		supplier = "Test TDS Supplier3"
+		category = "New TDS Category"
+		create_tax_withholding_category(
+			category_name=category,
+			rate=10,
+			from_date=self.prev_fy.year_start_date,
+			to_date=self.prev_fy.year_end_date,
+			account="TDS - _TC",
+			cumulative_threshold=30000,
+			tax_on_excess_amount=1,
+			round_off_tax_amount=1,
+		)
+		self.setup_party_with_category("Supplier", supplier, category)
+		prev_fy_date = add_days(self.prev_fy.year_end_date, -10)
+
+		for _ in range(2):
+			pi = create_purchase_invoice(supplier=supplier, posting_date=prev_fy_date, set_posting_time=True)
+			pi.submit()
+			invoices.append(pi)
+
+		pi3 = create_purchase_invoice(
+			supplier=supplier, rate=20000, posting_date=prev_fy_date, set_posting_time=True
+		)
+		pi3.submit()
+		invoices.append(pi3)
+
+		self.validate_tax_deduction(pi3, 1000)
+		self.validate_tax_withholding_entries(
+			"Purchase Invoice",
+			pi3.name,
+			[
+				self.get_tax_withholding_entry(
+					tax_withholding_category=category,
+					party_type="Supplier",
+					party=supplier,
+					taxable_doctype="Purchase Invoice",
+					taxable_name=pi3.name,
+					tax_rate=10.0,
+					taxable_amount=10000.0,
+					withholding_amount=0.0,
+					status="Settled",
+					withholding_doctype="Purchase Invoice",
+					withholding_name=pi3.name,
+					under_withheld_reason="Threshold Exemption",
+				),
+				self.get_tax_withholding_entry(
+					tax_withholding_category=category,
+					party_type="Supplier",
+					party=supplier,
+					taxable_doctype="Purchase Invoice",
+					taxable_name=pi3.name,
+					tax_rate=10.0,
+					taxable_amount=10000.0,
+					withholding_amount=1000.0,
+					status="Settled",
+					withholding_doctype="Purchase Invoice",
+					withholding_name=pi3.name,
+					under_withheld_reason=None,
+				),
+			],
+		)
+
+		# no excess, so no TDS
+		pi_curr = create_purchase_invoice(supplier=supplier, rate=30000)
+		pi_curr.submit()
+		invoices.append(pi_curr)
+		self.validate_tax_deduction(pi_curr, 0)
+
+		self.validate_tax_withholding_entries(
+			"Purchase Invoice",
+			pi_curr.name,
+			[
+				self.get_tax_withholding_entry(
+					tax_withholding_category=category,
+					party_type="Supplier",
+					party=supplier,
+					taxable_doctype="Purchase Invoice",
+					taxable_name=pi_curr.name,
+					tax_rate=10.0,
+					taxable_amount=30000.0,
+					withholding_amount=0.0,
+					status="Settled",
+					withholding_doctype="Purchase Invoice",
+					withholding_name=pi_curr.name,
+					under_withheld_reason="Threshold Exemption",
+				),
+			],
+		)
+		self.cleanup_invoices(invoices)
+
 	@ERPNextTestSuite.change_settings("Accounts Settings", {"delete_linked_ledger_entries": 1})
 	def test_tds_payment_entry_cancellation(self):
 		"""
@@ -3997,7 +4141,7 @@ def create_tax_withholding_category(
 	tax_deduction_basis="Net Total",
 ):
 	if not frappe.db.exists("Tax Withholding Category", category_name):
-		frappe.get_doc(
+		doc = frappe.get_doc(
 			{
 				"doctype": "Tax Withholding Category",
 				"name": category_name,
@@ -4018,6 +4162,22 @@ def create_tax_withholding_category(
 				"accounts": [{"company": "_Test Company", "account": account}],
 			}
 		).insert()
+	else:
+		doc = frappe.get_doc("Tax Withholding Category", category_name)
+		if not any(getdate(r.from_date) == getdate(from_date) for r in doc.rates):
+			doc.append(
+				"rates",
+				{
+					"from_date": from_date,
+					"to_date": to_date,
+					"tax_withholding_rate": rate,
+					"single_threshold": single_threshold,
+					"cumulative_threshold": cumulative_threshold,
+				},
+			)
+			doc.save()
+
+	return doc
 
 
 def create_lower_deduction_certificate(

erpnext/accounts/doctype/tax_withholding_entry/tax_withholding_entry.py

@@ -640,6 +640,7 @@ class TaxWithholdingController:
 			.where(entry.tax_withholding_category == category.name)
 			.where(entry.company == self.doc.company)
 			.where(entry.docstatus == 1)
+			.where(entry.taxable_date.between(category.from_date, category.to_date))
 			.groupby(entry.status)
 		)