feat: Income tax slab (#21399)

* Feat: Multiple tax as per new taxation rule

* patch:for multiple tax slab, fix: payroll and exemption validation

* Test: Fixture

* feat: income tax slab with other charges and tax exempted deduction components

* fix: added missing init file

* fix: Patch fixed

* fix: Patch fixed

* fix: test fixes

* fix: validate duplicate exemption declaration

* fix: payment entry test case

Co-authored-by: Anurag Mishra <mishranaman123@gmail.com>

erpnext/patches/v11_0/set_salary_component_properties.py

@@ -5,8 +5,7 @@ def execute():
 	frappe.reload_doc('hr', 'doctype', 'salary_detail')
 	frappe.reload_doc('hr', 'doctype', 'salary_component')
 
-	frappe.db.sql("update `tabSalary Component` set is_payable=1, is_tax_applicable=1 where type='Earning'")
-	frappe.db.sql("update `tabSalary Component` set is_payable=0 where type='Deduction'")
+	frappe.db.sql("update `tabSalary Component` set is_tax_applicable=1 where type='Earning'")
 
 	frappe.db.sql("""update `tabSalary Component` set variable_based_on_taxable_salary=1
 	    where type='Deduction' and name in ('TDS', 'Tax Deducted at Source')""")

erpnext/patches/v13_0/move_tax_slabs_from_payroll_period_to_income_tax_slab.py

@@ -0,0 +1,99 @@
+# Copyright (c) 2019, Frappe and Contributors
+# License: GNU General Public License v3. See license.txt
+
+from __future__ import unicode_literals
+
+import frappe
+from frappe.model.utils.rename_field import rename_field
+
+def execute():
+	if not frappe.db.table_exists("Payroll Period"):
+		return
+
+	for doctype in ("income_tax_slab", "salary_structure_assignment", "employee_other_income"):
+		frappe.reload_doc("hr", "doctype", doctype)
+
+
+	for company in frappe.get_all("Company"):
+		payroll_periods =  frappe.db.sql("""
+			SELECT
+				name, start_date, end_date, standard_tax_exemption_amount
+			FROM
+				`tabPayroll Period`
+			WHERE company=%s
+			ORDER BY start_date DESC
+		""", company.name, as_dict = 1)
+			
+		for i, period in enumerate(payroll_periods):
+			income_tax_slab = frappe.new_doc("Income Tax Slab")
+			income_tax_slab.name = "Tax Slab:" + period.name
+
+			if i == 0:
+				income_tax_slab.disabled = 0
+			else:
+				income_tax_slab.disabled = 1
+
+			income_tax_slab.effective_from = period.start_date
+			income_tax_slab.company = company.name
+			income_tax_slab.allow_tax_exemption = 1
+			income_tax_slab.standard_tax_exemption_amount = period.standard_tax_exemption_amount
+
+			income_tax_slab.flags.ignore_mandatory = True
+			income_tax_slab.submit()
+
+			frappe.db.sql(
+			""" UPDATE `tabTaxable Salary Slab`
+				SET parent = %s , parentfield = 'slabs' , parenttype = "Income Tax Slab"
+				WHERE parent = %s
+			""", (income_tax_slab.name, period.name), as_dict = 1)
+
+			if i == 0:
+				frappe.db.sql("""
+					UPDATE
+						`tabSalary Structure Assignment`
+					set
+						income_tax_slab = %s
+					where
+						company = %s
+						and from_date >= %s
+						and docstatus < 2
+				""", (income_tax_slab.name, company.name, period.start_date))
+
+	# move other incomes to separate document
+	migrated = []
+	proofs = frappe.get_all("Employee Tax Exemption Proof Submission",
+		filters = {'docstatus': 1},
+		fields =['payroll_period', 'employee', 'company', 'income_from_other_sources']
+	)
+	for proof in proofs:
+		if proof.income_from_other_sources:
+			employee_other_income = frappe.new_doc("Employee Other Income")
+			employee_other_income.employee = proof.employee
+			employee_other_income.payroll_period = proof.payroll_period
+			employee_other_income.company = proof.company
+			employee_other_income.amount = proof.income_from_other_sources
+
+			try:
+				employee_other_income.submit()
+				migrated.append([proof.employee, proof.payroll_period])
+			except:
+				pass
+
+	declerations = frappe.get_all("Employee Tax Exemption Declaration",
+		filters = {'docstatus': 1},
+		fields =['payroll_period', 'employee', 'company', 'income_from_other_sources']
+	)
+
+	for declaration in declerations:
+		if declaration.income_from_other_sources \
+				and [declaration.employee, declaration.payroll_period] not in migrated:
+			employee_other_income = frappe.new_doc("Employee Other Income")
+			employee_other_income.employee = declaration.employee
+			employee_other_income.payroll_period = declaration.payroll_period
+			employee_other_income.company = declaration.company
+			employee_other_income.amount = declaration.income_from_other_sources
+
+			try:
+				employee_other_income.submit()
+			except:
+				pass