Merge branch 'develop' into leave-opening-balance
diff --git a/erpnext/hr/doctype/holiday_list/test_holiday_list.py b/erpnext/hr/doctype/holiday_list/test_holiday_list.py
index c9239ed..aed901a 100644
--- a/erpnext/hr/doctype/holiday_list/test_holiday_list.py
+++ b/erpnext/hr/doctype/holiday_list/test_holiday_list.py
@@ -2,6 +2,7 @@
 # License: GNU General Public License v3. See license.txt
 
 import unittest
+from contextlib import contextmanager
 from datetime import timedelta
 
 import frappe
@@ -30,3 +31,24 @@
 		"holidays" : holiday_dates
 		}).insert()
 	return doc
+
+
+@contextmanager
+def set_holiday_list(holiday_list, company_name):
+	"""
+	Context manager for setting holiday list in tests
+	"""
+	try:
+		company = frappe.get_doc('Company', company_name)
+		previous_holiday_list = company.default_holiday_list
+
+		company.default_holiday_list = holiday_list
+		company.save()
+
+		yield
+
+	finally:
+		# restore holiday list setup
+		company = frappe.get_doc('Company', company_name)
+		company.default_holiday_list = previous_holiday_list
+		company.save()
diff --git a/erpnext/hr/doctype/leave_application/leave_application.js b/erpnext/hr/doctype/leave_application/leave_application.js
index 9e8cb55..85997a4 100755
--- a/erpnext/hr/doctype/leave_application/leave_application.js
+++ b/erpnext/hr/doctype/leave_application/leave_application.js
@@ -52,7 +52,7 @@
 	make_dashboard: function(frm) {
 		var leave_details;
 		let lwps;
-		if (frm.doc.employee) {
+		if (frm.doc.employee && frm.doc.from_date) {
 			frappe.call({
 				method: "erpnext.hr.doctype.leave_application.leave_application.get_leave_details",
 				async: false,
@@ -146,6 +146,7 @@
 	},
 
 	to_date: function(frm) {
+		frm.trigger("make_dashboard");
 		frm.trigger("half_day_datepicker");
 		frm.trigger("calculate_total_days");
 	},
diff --git a/erpnext/hr/doctype/leave_application/leave_application.py b/erpnext/hr/doctype/leave_application/leave_application.py
index ef5f4bc..0fa34ac 100755
--- a/erpnext/hr/doctype/leave_application/leave_application.py
+++ b/erpnext/hr/doctype/leave_application/leave_application.py
@@ -1,6 +1,7 @@
 # Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
 # License: GNU General Public License v3. See license.txt
 
+from typing import Dict
 
 import frappe
 from frappe import _
@@ -35,6 +36,10 @@
 class OverlapError(frappe.ValidationError): pass
 class AttendanceAlreadyMarkedError(frappe.ValidationError): pass
 class NotAnOptionalHoliday(frappe.ValidationError): pass
+class InsufficientLeaveBalanceError(frappe.ValidationError):
+	pass
+class LeaveAcrossAllocationsError(frappe.ValidationError):
+	pass
 
 from frappe.model.document import Document
 
@@ -135,21 +140,35 @@
 	def validate_dates_across_allocation(self):
 		if frappe.db.get_value("Leave Type", self.leave_type, "allow_negative"):
 			return
-		def _get_leave_allocation_record(date):
-			allocation = frappe.db.sql("""select name from `tabLeave Allocation`
-				where employee=%s and leave_type=%s and docstatus=1
-				and %s between from_date and to_date""", (self.employee, self.leave_type, date))
 
-			return allocation and allocation[0][0]
+		alloc_on_from_date, alloc_on_to_date = self.get_allocation_based_on_application_dates()
+
+		if not (alloc_on_from_date or alloc_on_to_date):
+			frappe.throw(_("Application period cannot be outside leave allocation period"))
+		elif self.is_separate_ledger_entry_required(alloc_on_from_date, alloc_on_to_date):
+			frappe.throw(_("Application period cannot be across two allocation records"), exc=LeaveAcrossAllocationsError)
+
+	def get_allocation_based_on_application_dates(self):
+		"""Returns allocation name, from and to dates for application dates"""
+		def _get_leave_allocation_record(date):
+			LeaveAllocation = frappe.qb.DocType("Leave Allocation")
+			allocation = (
+				frappe.qb.from_(LeaveAllocation)
+				.select(LeaveAllocation.name, LeaveAllocation.from_date, LeaveAllocation.to_date)
+				.where(
+					(LeaveAllocation.employee == self.employee)
+					& (LeaveAllocation.leave_type == self.leave_type)
+					& (LeaveAllocation.docstatus == 1)
+					& ((date >= LeaveAllocation.from_date) & (date <= LeaveAllocation.to_date))
+				)
+			).run(as_dict=True)
+
+			return allocation and allocation[0]
 
 		allocation_based_on_from_date = _get_leave_allocation_record(self.from_date)
 		allocation_based_on_to_date = _get_leave_allocation_record(self.to_date)
 
-		if not (allocation_based_on_from_date or allocation_based_on_to_date):
-			frappe.throw(_("Application period cannot be outside leave allocation period"))
-
-		elif allocation_based_on_from_date != allocation_based_on_to_date:
-			frappe.throw(_("Application period cannot be across two allocation records"))
+		return allocation_based_on_from_date, allocation_based_on_to_date
 
 	def validate_back_dated_application(self):
 		future_allocation = frappe.db.sql("""select name, from_date from `tabLeave Allocation`
@@ -261,15 +280,34 @@
 				frappe.throw(_("The day(s) on which you are applying for leave are holidays. You need not apply for leave."))
 
 			if not is_lwp(self.leave_type):
-				self.leave_balance = get_leave_balance_on(self.employee, self.leave_type, self.from_date, self.to_date,
-					consider_all_leaves_in_the_allocation_period=True)
-				if self.status != "Rejected" and (self.leave_balance < self.total_leave_days or not self.leave_balance):
-					if frappe.db.get_value("Leave Type", self.leave_type, "allow_negative"):
-						frappe.msgprint(_("Note: There is not enough leave balance for Leave Type {0}")
-							.format(self.leave_type))
-					else:
-						frappe.throw(_("There is not enough leave balance for Leave Type {0}")
-							.format(self.leave_type))
+				leave_balance = get_leave_balance_on(self.employee, self.leave_type, self.from_date, self.to_date,
+					consider_all_leaves_in_the_allocation_period=True, for_consumption=True)
+				self.leave_balance = leave_balance.get("leave_balance")
+				leave_balance_for_consumption = leave_balance.get("leave_balance_for_consumption")
+
+				if self.status != "Rejected" and (leave_balance_for_consumption < self.total_leave_days or not leave_balance_for_consumption):
+					self.show_insufficient_balance_message(leave_balance_for_consumption)
+
+	def show_insufficient_balance_message(self, leave_balance_for_consumption):
+		alloc_on_from_date, alloc_on_to_date = self.get_allocation_based_on_application_dates()
+
+		if frappe.db.get_value("Leave Type", self.leave_type, "allow_negative"):
+			if leave_balance_for_consumption != self.leave_balance:
+				msg = _("Warning: Insufficient leave balance for Leave Type {0} in this allocation.").format(frappe.bold(self.leave_type))
+				msg += "<br><br>"
+				msg += _("Actual leave balance is {0} but only {1} leave(s) can be consumed between {2} (Application Date) and {3} (Allocation Expiry).").format(
+					frappe.bold(self.leave_balance), frappe.bold(leave_balance_for_consumption),
+					frappe.bold(formatdate(self.from_date)),
+					frappe.bold(formatdate(alloc_on_from_date.to_date)))
+				msg += "<br>"
+				msg += _("Remaining leaves would be compensated in the next allocation.")
+			else:
+				msg = _("Warning: Insufficient leave balance for Leave Type {0}.").format(frappe.bold(self.leave_type))
+
+			frappe.msgprint(msg, title=_("Warning"), indicator="orange")
+		else:
+			frappe.throw(_("Insufficient leave balance for Leave Type {0}").format(frappe.bold(self.leave_type)),
+				exc=InsufficientLeaveBalanceError, title=_("Insufficient Balance"))
 
 	def validate_leave_overlap(self):
 		if not self.name:
@@ -426,54 +464,111 @@
 		if self.status != 'Approved' and submit:
 			return
 
-		expiry_date = get_allocation_expiry(self.employee, self.leave_type,
+		expiry_date = get_allocation_expiry_for_cf_leaves(self.employee, self.leave_type,
 			self.to_date, self.from_date)
-
 		lwp = frappe.db.get_value("Leave Type", self.leave_type, "is_lwp")
 
 		if expiry_date:
 			self.create_ledger_entry_for_intermediate_allocation_expiry(expiry_date, submit, lwp)
 		else:
-			raise_exception = True
-			if frappe.flags.in_patch:
-				raise_exception=False
+			alloc_on_from_date, alloc_on_to_date = self.get_allocation_based_on_application_dates()
+			if self.is_separate_ledger_entry_required(alloc_on_from_date, alloc_on_to_date):
+				# required only if negative balance is allowed for leave type
+				# else will be stopped in validation itself
+				self.create_separate_ledger_entries(alloc_on_from_date, alloc_on_to_date, submit, lwp)
+			else:
+				raise_exception = False if frappe.flags.in_patch else True
+				args = dict(
+					leaves=self.total_leave_days * -1,
+					from_date=self.from_date,
+					to_date=self.to_date,
+					is_lwp=lwp,
+					holiday_list=get_holiday_list_for_employee(self.employee, raise_exception=raise_exception) or ''
+				)
+				create_leave_ledger_entry(self, args, submit)
 
-			args = dict(
-				leaves=self.total_leave_days * -1,
+	def is_separate_ledger_entry_required(self, alloc_on_from_date=None, alloc_on_to_date=None) -> bool:
+		"""Checks if application dates fall in separate allocations"""
+		if ((alloc_on_from_date and not alloc_on_to_date)
+			or (not alloc_on_from_date and alloc_on_to_date)
+			or (alloc_on_from_date and alloc_on_to_date and alloc_on_from_date.name != alloc_on_to_date.name)):
+			return True
+		return False
+
+	def create_separate_ledger_entries(self, alloc_on_from_date, alloc_on_to_date, submit, lwp):
+		"""Creates separate ledger entries for application period falling into separate allocations"""
+		# for creating separate ledger entries existing allocation periods should be consecutive
+		if submit and alloc_on_from_date and alloc_on_to_date and add_days(alloc_on_from_date.to_date, 1) != alloc_on_to_date.from_date:
+			frappe.throw(_("Leave Application period cannot be across two non-consecutive leave allocations {0} and {1}.").format(
+				get_link_to_form("Leave Allocation", alloc_on_from_date.name), get_link_to_form("Leave Allocation", alloc_on_to_date)))
+
+		raise_exception = False if frappe.flags.in_patch else True
+
+		if alloc_on_from_date:
+			first_alloc_end = alloc_on_from_date.to_date
+			second_alloc_start = add_days(alloc_on_from_date.to_date, 1)
+		else:
+			first_alloc_end = add_days(alloc_on_to_date.from_date, -1)
+			second_alloc_start = alloc_on_to_date.from_date
+
+		leaves_in_first_alloc = get_number_of_leave_days(self.employee, self.leave_type,
+			self.from_date, first_alloc_end, self.half_day, self.half_day_date)
+		leaves_in_second_alloc = get_number_of_leave_days(self.employee, self.leave_type,
+			second_alloc_start, self.to_date, self.half_day, self.half_day_date)
+
+		args = dict(
+			is_lwp=lwp,
+			holiday_list=get_holiday_list_for_employee(self.employee, raise_exception=raise_exception) or ''
+		)
+
+		if leaves_in_first_alloc:
+			args.update(dict(
 				from_date=self.from_date,
+				to_date=first_alloc_end,
+				leaves=leaves_in_first_alloc * -1
+			))
+			create_leave_ledger_entry(self, args, submit)
+
+		if leaves_in_second_alloc:
+			args.update(dict(
+				from_date=second_alloc_start,
 				to_date=self.to_date,
+				leaves=leaves_in_second_alloc * -1
+			))
+			create_leave_ledger_entry(self, args, submit)
+
+	def create_ledger_entry_for_intermediate_allocation_expiry(self, expiry_date, submit, lwp):
+		"""Splits leave application into two ledger entries to consider expiry of allocation"""
+		raise_exception = False if frappe.flags.in_patch else True
+
+		leaves = get_number_of_leave_days(self.employee, self.leave_type,
+			self.from_date, expiry_date, self.half_day, self.half_day_date)
+
+		if leaves:
+			args = dict(
+				from_date=self.from_date,
+				to_date=expiry_date,
+				leaves=leaves * -1,
 				is_lwp=lwp,
 				holiday_list=get_holiday_list_for_employee(self.employee, raise_exception=raise_exception) or ''
 			)
 			create_leave_ledger_entry(self, args, submit)
 
-	def create_ledger_entry_for_intermediate_allocation_expiry(self, expiry_date, submit, lwp):
-		''' splits leave application into two ledger entries to consider expiry of allocation '''
-
-		raise_exception = True
-		if frappe.flags.in_patch:
-			raise_exception=False
-
-		args = dict(
-			from_date=self.from_date,
-			to_date=expiry_date,
-			leaves=(date_diff(expiry_date, self.from_date) + 1) * -1,
-			is_lwp=lwp,
-			holiday_list=get_holiday_list_for_employee(self.employee, raise_exception=raise_exception) or ''
-		)
-		create_leave_ledger_entry(self, args, submit)
-
 		if getdate(expiry_date) != getdate(self.to_date):
 			start_date = add_days(expiry_date, 1)
-			args.update(dict(
-				from_date=start_date,
-				to_date=self.to_date,
-				leaves=date_diff(self.to_date, expiry_date) * -1
-			))
-			create_leave_ledger_entry(self, args, submit)
+			leaves = get_number_of_leave_days(self.employee, self.leave_type,
+				start_date, self.to_date, self.half_day, self.half_day_date)
+
+			if leaves:
+				args.update(dict(
+					from_date=start_date,
+					to_date=self.to_date,
+					leaves=leaves * -1
+				))
+				create_leave_ledger_entry(self, args, submit)
 
 
-def get_allocation_expiry(employee, leave_type, to_date, from_date):
+def get_allocation_expiry_for_cf_leaves(employee, leave_type, to_date, from_date):
 	''' Returns expiry of carry forward allocation in leave ledger entry '''
 	expiry =  frappe.get_all("Leave Ledger Entry",
 		filters={
@@ -481,7 +576,8 @@
 			'leave_type': leave_type,
 			'is_carry_forward': 1,
 			'transaction_type': 'Leave Allocation',
-			'to_date': ['between', (from_date, to_date)]
+			'to_date': ['between', (from_date, to_date)],
+			'docstatus': 1
 		},fields=['to_date'])
 	return expiry[0]['to_date'] if expiry else None
 
@@ -515,6 +611,7 @@
 			'to_date': ('>=', date),
 			'employee': employee,
 			'leave_type': allocation.leave_type,
+			'docstatus': 1
 		}, 'SUM(total_leaves_allocated)') or 0
 
 		remaining_leaves = get_leave_balance_on(employee, d, date, to_date = allocation.to_date,
@@ -522,29 +619,28 @@
 
 		end_date = allocation.to_date
 		leaves_taken = get_leaves_for_period(employee, d, allocation.from_date, end_date) * -1
-		leaves_pending = get_pending_leaves_for_period(employee, d, allocation.from_date, end_date)
+		leaves_pending = get_leaves_pending_approval_for_period(employee, d, allocation.from_date, end_date)
 
 		leave_allocation[d] = {
 			"total_leaves": total_allocated_leaves,
 			"expired_leaves": total_allocated_leaves - (remaining_leaves + leaves_taken),
 			"leaves_taken": leaves_taken,
-			"pending_leaves": leaves_pending,
+			"leaves_pending_approval": leaves_pending,
 			"remaining_leaves": remaining_leaves}
 
 	#is used in set query
-	lwps = frappe.get_list("Leave Type", filters = {"is_lwp": 1})
-	lwps = [lwp.name for lwp in lwps]
+	lwp = frappe.get_list("Leave Type", filters={"is_lwp": 1}, pluck="name")
 
-	ret = {
-		'leave_allocation': leave_allocation,
-		'leave_approver': get_leave_approver(employee),
-		'lwps': lwps
+	return {
+		"leave_allocation": leave_allocation,
+		"leave_approver": get_leave_approver(employee),
+		"lwps": lwp
 	}
 
-	return ret
 
 @frappe.whitelist()
-def get_leave_balance_on(employee, leave_type, date, to_date=None, consider_all_leaves_in_the_allocation_period=False):
+def get_leave_balance_on(employee, leave_type, date, to_date=None,
+	consider_all_leaves_in_the_allocation_period=False, for_consumption=False):
 	'''
 		Returns leave balance till date
 		:param employee: employee name
@@ -552,6 +648,11 @@
 		:param date: date to check balance on
 		:param to_date: future date to check for allocation expiry
 		:param consider_all_leaves_in_the_allocation_period: consider all leaves taken till the allocation end date
+		:param for_consumption: flag to check if leave balance is required for consumption or display
+			eg: employee has leave balance = 10 but allocation is expiring in 1 day so employee can only consume 1 leave
+			in this case leave_balance = 10 but leave_balance_for_consumption = 1
+			if True, returns a dict eg: {'leave_balance': 10, 'leave_balance_for_consumption': 1}
+			else, returns leave_balance (in this case 10)
 	'''
 
 	if not to_date:
@@ -561,11 +662,17 @@
 	allocation = allocation_records.get(leave_type, frappe._dict())
 
 	end_date = allocation.to_date if consider_all_leaves_in_the_allocation_period else date
-	expiry = get_allocation_expiry(employee, leave_type, to_date, date)
+	cf_expiry = get_allocation_expiry_for_cf_leaves(employee, leave_type, to_date, date)
 
 	leaves_taken = get_leaves_for_period(employee, leave_type, allocation.from_date, end_date)
 
-	return get_remaining_leaves(allocation, leaves_taken, date, expiry)
+	remaining_leaves = get_remaining_leaves(allocation, leaves_taken, date, cf_expiry)
+
+	if for_consumption:
+		return remaining_leaves
+	else:
+		return remaining_leaves.get('leave_balance')
+
 
 def get_leave_allocation_records(employee, date, leave_type=None):
 	"""Returns the total allocated leaves and carry forwarded leaves based on ledger entries"""
@@ -614,7 +721,7 @@
 		}))
 	return allocated_leaves
 
-def get_pending_leaves_for_period(employee, leave_type, from_date, to_date):
+def get_leaves_pending_approval_for_period(employee, leave_type, from_date, to_date):
 	''' Returns leaves that are pending approval '''
 	leaves = frappe.get_all("Leave Application",
 		filters={
@@ -628,38 +735,44 @@
 		}, fields=['SUM(total_leave_days) as leaves'])[0]
 	return leaves['leaves'] if leaves['leaves'] else 0.0
 
-def get_remaining_leaves(allocation, leaves_taken, date, expiry):
-	''' Returns minimum leaves remaining after comparing with remaining days for allocation expiry '''
+def get_remaining_leaves(allocation, leaves_taken, date, cf_expiry) -> Dict[str, float]:
+	'''Returns a dict of leave_balance and leave_balance_for_consumption
+	leave_balance returns the available leave balance
+	leave_balance_for_consumption returns the minimum leaves remaining after comparing with remaining days for allocation expiry
+	'''
 	def _get_remaining_leaves(remaining_leaves, end_date):
-
+		''' Returns minimum leaves remaining after comparing with remaining days for allocation expiry '''
 		if remaining_leaves > 0:
 			remaining_days = date_diff(end_date, date) + 1
 			remaining_leaves = min(remaining_days, remaining_leaves)
 
 		return remaining_leaves
 
-	total_leaves = flt(allocation.total_leaves_allocated) + flt(leaves_taken)
+	leave_balance = leave_balance_for_consumption = flt(allocation.total_leaves_allocated) + flt(leaves_taken)
 
-	if expiry and allocation.unused_leaves:
-		remaining_leaves = flt(allocation.unused_leaves) + flt(leaves_taken)
-		remaining_leaves = _get_remaining_leaves(remaining_leaves, expiry)
+	# balance for carry forwarded leaves
+	if cf_expiry and allocation.unused_leaves:
+		cf_leaves = flt(allocation.unused_leaves) + flt(leaves_taken)
+		remaining_cf_leaves = _get_remaining_leaves(cf_leaves, cf_expiry)
 
-		total_leaves = flt(allocation.new_leaves_allocated) + flt(remaining_leaves)
+		leave_balance = flt(allocation.new_leaves_allocated) + flt(cf_leaves)
+		leave_balance_for_consumption = flt(allocation.new_leaves_allocated) + flt(remaining_cf_leaves)
 
-	return _get_remaining_leaves(total_leaves, allocation.to_date)
+	remaining_leaves = _get_remaining_leaves(leave_balance_for_consumption, allocation.to_date)
+	return frappe._dict(leave_balance=leave_balance, leave_balance_for_consumption=remaining_leaves)
 
-def get_leaves_for_period(employee, leave_type, from_date, to_date, do_not_skip_expired_leaves=False):
+def get_leaves_for_period(employee, leave_type, from_date, to_date, skip_expired_leaves=True):
 	leave_entries = get_leave_entries(employee, leave_type, from_date, to_date)
 	leave_days = 0
 
 	for leave_entry in leave_entries:
 		inclusive_period = leave_entry.from_date >= getdate(from_date) and leave_entry.to_date <= getdate(to_date)
 
-		if  inclusive_period and leave_entry.transaction_type == 'Leave Encashment':
+		if inclusive_period and leave_entry.transaction_type == 'Leave Encashment':
 			leave_days += leave_entry.leaves
 
 		elif inclusive_period and leave_entry.transaction_type == 'Leave Allocation' and leave_entry.is_expired \
-			and (do_not_skip_expired_leaves or not skip_expiry_leaves(leave_entry, to_date)):
+			and not skip_expired_leaves:
 			leave_days += leave_entry.leaves
 
 		elif leave_entry.transaction_type == 'Leave Application':
@@ -681,11 +794,6 @@
 
 	return leave_days
 
-def skip_expiry_leaves(leave_entry, date):
-	''' Checks whether the expired leaves coincide with the to_date of leave balance check.
-		This allows backdated leave entry creation for non carry forwarded allocation '''
-	end_date = frappe.db.get_value("Leave Allocation", {'name': leave_entry.transaction_name}, ['to_date'])
-	return True if end_date == date and not leave_entry.is_carry_forward else False
 
 def get_leave_entries(employee, leave_type, from_date, to_date):
 	''' Returns leave entries between from_date and to_date. '''
diff --git a/erpnext/hr/doctype/leave_application/leave_application_dashboard.html b/erpnext/hr/doctype/leave_application/leave_application_dashboard.html
index 9f667a6..e755322 100644
--- a/erpnext/hr/doctype/leave_application/leave_application_dashboard.html
+++ b/erpnext/hr/doctype/leave_application/leave_application_dashboard.html
@@ -4,11 +4,11 @@
 	<thead>
 		<tr>
 			<th style="width: 16%">{{ __("Leave Type") }}</th>
-			<th style="width: 16%" class="text-right">{{ __("Total Allocated Leave") }}</th>
-			<th style="width: 16%" class="text-right">{{ __("Expired Leave") }}</th>
-			<th style="width: 16%" class="text-right">{{ __("Used Leave") }}</th>
-			<th style="width: 16%" class="text-right">{{ __("Pending Leave") }}</th>
-			<th style="width: 16%" class="text-right">{{ __("Available Leave") }}</th>
+			<th style="width: 16%" class="text-right">{{ __("Total Allocated Leave(s)") }}</th>
+			<th style="width: 16%" class="text-right">{{ __("Expired Leave(s)") }}</th>
+			<th style="width: 16%" class="text-right">{{ __("Used Leave(s)") }}</th>
+			<th style="width: 16%" class="text-right">{{ __("Leave(s) Pending Approval") }}</th>
+			<th style="width: 16%" class="text-right">{{ __("Available Leave(s)") }}</th>
 		</tr>
 	</thead>
 	<tbody>
@@ -18,7 +18,7 @@
 				<td class="text-right"> {%= value["total_leaves"] %} </td>
 				<td class="text-right"> {%= value["expired_leaves"] %} </td>
 				<td class="text-right"> {%= value["leaves_taken"] %} </td>
-				<td class="text-right"> {%= value["pending_leaves"] %} </td>
+				<td class="text-right"> {%= value["leaves_pending_approval"] %} </td>
 				<td class="text-right"> {%= value["remaining_leaves"] %} </td>
 			</tr>
 		{% } %}
diff --git a/erpnext/hr/doctype/leave_application/test_leave_application.py b/erpnext/hr/doctype/leave_application/test_leave_application.py
index 7b3aa49..87d79b3 100644
--- a/erpnext/hr/doctype/leave_application/test_leave_application.py
+++ b/erpnext/hr/doctype/leave_application/test_leave_application.py
@@ -17,12 +17,16 @@
 )
 
 from erpnext.hr.doctype.employee.test_employee import make_employee
+from erpnext.hr.doctype.holiday_list.test_holiday_list import set_holiday_list
 from erpnext.hr.doctype.leave_allocation.test_leave_allocation import create_leave_allocation
 from erpnext.hr.doctype.leave_application.leave_application import (
+	InsufficientLeaveBalanceError,
+	LeaveAcrossAllocationsError,
 	LeaveDayBlockedError,
 	NotAnOptionalHoliday,
 	OverlapError,
 	get_leave_balance_on,
+	get_leave_details,
 )
 from erpnext.hr.doctype.leave_policy_assignment.leave_policy_assignment import (
 	create_assignment_for_multiple_employees,
@@ -33,7 +37,7 @@
 	make_leave_application,
 )
 
-test_dependencies = ["Leave Allocation", "Leave Block List", "Employee"]
+test_dependencies = ["Leave Type", "Leave Allocation", "Leave Block List", "Employee"]
 
 _test_records = [
 	{
@@ -72,15 +76,24 @@
 class TestLeaveApplication(unittest.TestCase):
 	def setUp(self):
 		for dt in ["Leave Application", "Leave Allocation", "Salary Slip", "Leave Ledger Entry"]:
-			frappe.db.sql("DELETE FROM `tab%s`" % dt) #nosec
+			frappe.db.delete(dt)
 
 		frappe.set_user("Administrator")
 		set_leave_approver()
 
-		frappe.db.sql("delete from tabAttendance where employee='_T-Employee-00001'")
+		frappe.db.delete("Attendance", {"employee": "_T-Employee-00001"})
+		self.holiday_list = make_holiday_list()
+
+		if not frappe.db.exists("Leave Type", "_Test Leave Type"):
+			frappe.get_doc(dict(
+				leave_type_name="_Test Leave Type",
+				doctype="Leave Type",
+				include_holiday=True
+			)).insert()
 
 	def tearDown(self):
 		frappe.db.rollback()
+		frappe.set_user("Administrator")
 
 	def _clear_roles(self):
 		frappe.db.sql("""delete from `tabHas Role` where parent in
@@ -95,6 +108,132 @@
 		application.to_date = "2013-01-05"
 		return application
 
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
+	def test_validate_application_across_allocations(self):
+		# Test validation for application dates when negative balance is disabled
+		frappe.delete_doc_if_exists("Leave Type", "Test Leave Validation", force=1)
+		leave_type = frappe.get_doc(dict(
+			leave_type_name="Test Leave Validation",
+			doctype="Leave Type",
+			allow_negative=False
+		)).insert()
+
+		employee = get_employee()
+		date = getdate()
+		first_sunday = get_first_sunday(self.holiday_list, for_date=get_year_start(date))
+
+		leave_application = frappe.get_doc(dict(
+			doctype='Leave Application',
+			employee=employee.name,
+			leave_type=leave_type.name,
+			from_date=add_days(first_sunday, 1),
+			to_date=add_days(first_sunday, 4),
+			company="_Test Company",
+			status="Approved",
+			leave_approver = 'test@example.com'
+		))
+		# Application period cannot be outside leave allocation period
+		self.assertRaises(frappe.ValidationError, leave_application.insert)
+
+		make_allocation_record(leave_type=leave_type.name, from_date=get_year_start(date), to_date=get_year_ending(date))
+
+		leave_application = frappe.get_doc(dict(
+			doctype='Leave Application',
+			employee=employee.name,
+			leave_type=leave_type.name,
+			from_date=add_days(first_sunday, -10),
+			to_date=add_days(first_sunday, 1),
+			company="_Test Company",
+			status="Approved",
+			leave_approver = 'test@example.com'
+		))
+
+		# Application period cannot be across two allocation records
+		self.assertRaises(LeaveAcrossAllocationsError, leave_application.insert)
+
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
+	def test_insufficient_leave_balance_validation(self):
+		# CASE 1: Validation when allow negative is disabled
+		frappe.delete_doc_if_exists("Leave Type", "Test Leave Validation", force=1)
+		leave_type = frappe.get_doc(dict(
+			leave_type_name="Test Leave Validation",
+			doctype="Leave Type",
+			allow_negative=False
+		)).insert()
+
+		employee = get_employee()
+		date = getdate()
+		first_sunday = get_first_sunday(self.holiday_list, for_date=get_year_start(date))
+
+		# allocate 2 leaves, apply for more
+		make_allocation_record(leave_type=leave_type.name, from_date=get_year_start(date), to_date=get_year_ending(date), leaves=2)
+		leave_application = frappe.get_doc(dict(
+			doctype='Leave Application',
+			employee=employee.name,
+			leave_type=leave_type.name,
+			from_date=add_days(first_sunday, 1),
+			to_date=add_days(first_sunday, 3),
+			company="_Test Company",
+			status="Approved",
+			leave_approver = 'test@example.com'
+		))
+		self.assertRaises(InsufficientLeaveBalanceError, leave_application.insert)
+
+		# CASE 2: Allows creating application with a warning message when allow negative is enabled
+		frappe.db.set_value("Leave Type", "Test Leave Validation", "allow_negative", True)
+		make_leave_application(employee.name, add_days(first_sunday, 1), add_days(first_sunday, 3), leave_type.name)
+
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
+	def test_separate_leave_ledger_entry_for_boundary_applications(self):
+		# When application falls in 2 different allocations and Allow Negative is enabled
+		# creates separate leave ledger entries
+		frappe.delete_doc_if_exists("Leave Type", "Test Leave Validation", force=1)
+		leave_type = frappe.get_doc(dict(
+			leave_type_name="Test Leave Validation",
+			doctype="Leave Type",
+			allow_negative=True
+		)).insert()
+
+		employee = get_employee()
+		date = getdate()
+		year_start = getdate(get_year_start(date))
+		year_end = getdate(get_year_ending(date))
+
+		make_allocation_record(leave_type=leave_type.name, from_date=year_start, to_date=year_end)
+		# application across allocations
+
+		# CASE 1: from date has no allocation, to date has an allocation / both dates have allocation
+		application = make_leave_application(employee.name, add_days(year_start, -10), add_days(year_start, 3), leave_type.name)
+
+		# 2 separate leave ledger entries
+		ledgers = frappe.db.get_all("Leave Ledger Entry", {
+			"transaction_type": "Leave Application",
+			"transaction_name": application.name
+		}, ["leaves", "from_date", "to_date"], order_by="from_date")
+		self.assertEqual(len(ledgers), 2)
+
+		self.assertEqual(ledgers[0].from_date, application.from_date)
+		self.assertEqual(ledgers[0].to_date, add_days(year_start, -1))
+
+		self.assertEqual(ledgers[1].from_date, year_start)
+		self.assertEqual(ledgers[1].to_date, application.to_date)
+
+		# CASE 2: from date has an allocation, to date has no allocation
+		application = make_leave_application(employee.name, add_days(year_end, -3), add_days(year_end, 5), leave_type.name)
+
+		# 2 separate leave ledger entries
+		ledgers = frappe.db.get_all("Leave Ledger Entry", {
+			"transaction_type": "Leave Application",
+			"transaction_name": application.name
+		}, ["leaves", "from_date", "to_date"], order_by="from_date")
+		self.assertEqual(len(ledgers), 2)
+
+		self.assertEqual(ledgers[0].from_date, application.from_date)
+		self.assertEqual(ledgers[0].to_date, year_end)
+
+		self.assertEqual(ledgers[1].from_date, add_days(year_end, 1))
+		self.assertEqual(ledgers[1].to_date, application.to_date)
+
 	def test_overwrite_attendance(self):
 		'''check attendance is automatically created on leave approval'''
 		make_allocation_record()
@@ -119,6 +258,7 @@
 		for d in ('2018-01-01', '2018-01-02', '2018-01-03'):
 			self.assertTrue(getdate(d) in dates)
 
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
 	def test_attendance_for_include_holidays(self):
 		# Case 1: leave type with 'Include holidays within leaves as leaves' enabled
 		frappe.delete_doc_if_exists("Leave Type", "Test Include Holidays", force=1)
@@ -131,18 +271,17 @@
 		date = getdate()
 		make_allocation_record(leave_type=leave_type.name, from_date=get_year_start(date), to_date=get_year_ending(date))
 
-		holiday_list = make_holiday_list()
 		employee = get_employee()
-		frappe.db.set_value("Company", employee.company, "default_holiday_list", holiday_list)
-		first_sunday = get_first_sunday(holiday_list)
+		first_sunday = get_first_sunday(self.holiday_list)
 
-		leave_application = make_leave_application(employee.name, first_sunday, add_days(first_sunday, 3), leave_type.name)
+		leave_application = make_leave_application(employee.name, add_days(first_sunday, 1), add_days(first_sunday, 4), leave_type.name)
 		leave_application.reload()
 		self.assertEqual(leave_application.total_leave_days, 4)
 		self.assertEqual(frappe.db.count('Attendance', {'leave_application': leave_application.name}), 4)
 
 		leave_application.cancel()
 
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
 	def test_attendance_update_for_exclude_holidays(self):
 		# Case 2: leave type with 'Include holidays within leaves as leaves' disabled
 		frappe.delete_doc_if_exists("Leave Type", "Test Do Not Include Holidays", force=1)
@@ -155,10 +294,8 @@
 		date = getdate()
 		make_allocation_record(leave_type=leave_type.name, from_date=get_year_start(date), to_date=get_year_ending(date))
 
-		holiday_list = make_holiday_list()
 		employee = get_employee()
-		frappe.db.set_value("Company", employee.company, "default_holiday_list", holiday_list)
-		first_sunday = get_first_sunday(holiday_list)
+		first_sunday = get_first_sunday(self.holiday_list)
 
 		# already marked attendance on a holiday should be deleted in this case
 		config = {
@@ -320,16 +457,14 @@
 		application.half_day_date = "2013-01-05"
 		application.insert()
 
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
 	def test_optional_leave(self):
 		leave_period = get_leave_period()
 		today = nowdate()
 		holiday_list = 'Test Holiday List for Optional Holiday'
 		employee = get_employee()
 
-		default_holiday_list = make_holiday_list()
-		frappe.db.set_value("Company", employee.company, "default_holiday_list", default_holiday_list)
-		first_sunday = get_first_sunday(default_holiday_list)
-
+		first_sunday = get_first_sunday(self.holiday_list)
 		optional_leave_date = add_days(first_sunday, 1)
 
 		if not frappe.db.exists('Holiday List', holiday_list):
@@ -503,11 +638,13 @@
 			leave_type_name="_Test_CF_leave_expiry",
 			is_carry_forward=1,
 			expire_carry_forwarded_leaves_after_days=90)
-		leave_type.submit()
+		leave_type.insert()
 
 		create_carry_forwarded_allocation(employee, leave_type)
+		details = get_leave_balance_on(employee.name, leave_type.name, nowdate(), add_days(nowdate(), 8), for_consumption=True)
 
-		self.assertEqual(get_leave_balance_on(employee.name, leave_type.name, nowdate(), add_days(nowdate(), 8)), 21)
+		self.assertEqual(details.leave_balance_for_consumption, 21)
+		self.assertEqual(details.leave_balance, 30)
 
 	def test_earned_leaves_creation(self):
 
@@ -561,7 +698,14 @@
 	# test to not consider current leave in leave balance while submitting
 	def test_current_leave_on_submit(self):
 		employee = get_employee()
-		leave_type = 'Sick leave'
+
+		leave_type = 'Sick Leave'
+		if not frappe.db.exists('Leave Type', leave_type):
+			frappe.get_doc(dict(
+				leave_type_name=leave_type,
+				doctype='Leave Type'
+			)).insert()
+
 		allocation = frappe.get_doc(dict(
 			doctype = 'Leave Allocation',
 			employee = employee.name,
@@ -704,6 +848,35 @@
 		employee.leave_approver = ""
 		employee.save()
 
+	@set_holiday_list('Salary Slip Test Holiday List', '_Test Company')
+	def test_get_leave_details_for_dashboard(self):
+		employee = get_employee()
+		date = getdate()
+		year_start = getdate(get_year_start(date))
+		year_end = getdate(get_year_ending(date))
+
+		# ALLOCATION = 30
+		allocation = make_allocation_record(employee=employee.name, from_date=year_start, to_date=year_end)
+
+		# USED LEAVES = 4
+		first_sunday = get_first_sunday(self.holiday_list)
+		leave_application = make_leave_application(employee.name, add_days(first_sunday, 1), add_days(first_sunday, 4), '_Test Leave Type')
+		leave_application.reload()
+
+		# LEAVES PENDING APPROVAL = 1
+		leave_application = make_leave_application(employee.name, add_days(first_sunday, 5), add_days(first_sunday, 5),
+			'_Test Leave Type', submit=False)
+		leave_application.status = 'Open'
+		leave_application.save()
+
+		details = get_leave_details(employee.name, allocation.from_date)
+		leave_allocation = details['leave_allocation']['_Test Leave Type']
+		self.assertEqual(leave_allocation['total_leaves'], 30)
+		self.assertEqual(leave_allocation['leaves_taken'], 4)
+		self.assertEqual(leave_allocation['expired_leaves'], 0)
+		self.assertEqual(leave_allocation['leaves_pending_approval'], 1)
+		self.assertEqual(leave_allocation['remaining_leaves'], 26)
+
 
 def create_carry_forwarded_allocation(employee, leave_type):
 		# initial leave allocation
@@ -725,19 +898,22 @@
 			carry_forward=1)
 		leave_allocation.submit()
 
-def make_allocation_record(employee=None, leave_type=None, from_date=None, to_date=None):
+def make_allocation_record(employee=None, leave_type=None, from_date=None, to_date=None, carry_forward=False, leaves=None):
 	allocation = frappe.get_doc({
 		"doctype": "Leave Allocation",
 		"employee": employee or "_T-Employee-00001",
 		"leave_type": leave_type or "_Test Leave Type",
 		"from_date": from_date or "2013-01-01",
 		"to_date": to_date or "2019-12-31",
-		"new_leaves_allocated": 30
+		"new_leaves_allocated": leaves or 30,
+		"carry_forward": carry_forward
 	})
 
 	allocation.insert(ignore_permissions=True)
 	allocation.submit()
 
+	return allocation
+
 def get_employee():
 	return frappe.get_doc("Employee", "_T-Employee-00001")
 
@@ -782,9 +958,10 @@
 	allocate_leave.submit()
 
 
-def get_first_sunday(holiday_list):
-	month_start_date = get_first_day(nowdate())
-	month_end_date = get_last_day(nowdate())
+def get_first_sunday(holiday_list, for_date=None):
+	date = for_date or getdate()
+	month_start_date = get_first_day(date)
+	month_end_date = get_last_day(date)
 	first_sunday = frappe.db.sql("""
 		select holiday_date from `tabHoliday`
 		where parent = %s
diff --git a/erpnext/hr/doctype/leave_ledger_entry/leave_ledger_entry.py b/erpnext/hr/doctype/leave_ledger_entry/leave_ledger_entry.py
index 5c5299e..a5923e0 100644
--- a/erpnext/hr/doctype/leave_ledger_entry/leave_ledger_entry.py
+++ b/erpnext/hr/doctype/leave_ledger_entry/leave_ledger_entry.py
@@ -171,7 +171,7 @@
 	''' Expires remaining leaves in the on carried forward allocation '''
 	from erpnext.hr.doctype.leave_application.leave_application import get_leaves_for_period
 	leaves_taken = get_leaves_for_period(allocation.employee, allocation.leave_type,
-		allocation.from_date, allocation.to_date, do_not_skip_expired_leaves=True)
+		allocation.from_date, allocation.to_date, skip_expired_leaves=False)
 	leaves = flt(allocation.leaves) + flt(leaves_taken)
 
 	# allow expired leaves entry to be created
diff --git a/erpnext/hr/doctype/leave_policy_assignment/test_leave_policy_assignment.py b/erpnext/hr/doctype/leave_policy_assignment/test_leave_policy_assignment.py
index a19ddce..27e4f14 100644
--- a/erpnext/hr/doctype/leave_policy_assignment/test_leave_policy_assignment.py
+++ b/erpnext/hr/doctype/leave_policy_assignment/test_leave_policy_assignment.py
@@ -4,7 +4,7 @@
 import unittest
 
 import frappe
-from frappe.utils import add_months, get_first_day, get_last_day, getdate
+from frappe.utils import add_days, add_months, get_first_day, get_last_day, getdate
 
 from erpnext.hr.doctype.leave_application.test_leave_application import (
 	get_employee,
@@ -95,9 +95,12 @@
 			"leave_policy": leave_policy.name,
 			"leave_period": leave_period.name
 		}
+
+		# second last day of the month
+		# leaves allocated should be 0 since it is an earned leave and allocation happens via scheduler based on set frequency
+		frappe.flags.current_date = add_days(get_last_day(getdate()), -1)
 		leave_policy_assignments = create_assignment_for_multiple_employees([self.employee.name], frappe._dict(data))
 
-		# leaves allocated should be 0 since it is an earned leave and allocation happens via scheduler based on set frequency
 		leaves_allocated = frappe.db.get_value("Leave Allocation", {
 			"leave_policy_assignment": leave_policy_assignments[0]
 		}, "total_leaves_allocated")
diff --git a/erpnext/hr/report/employee_leave_balance/employee_leave_balance.py b/erpnext/hr/report/employee_leave_balance/employee_leave_balance.py
index b375b18..3324ede 100644
--- a/erpnext/hr/report/employee_leave_balance/employee_leave_balance.py
+++ b/erpnext/hr/report/employee_leave_balance/employee_leave_balance.py
@@ -3,18 +3,21 @@
 
 
 from itertools import groupby
+from typing import Dict, List, Tuple
 
 import frappe
 from frappe import _
-from frappe.utils import add_days
+from frappe.utils import add_days, getdate
 
+from erpnext.hr.doctype.leave_allocation.leave_allocation import get_previous_allocation
 from erpnext.hr.doctype.leave_application.leave_application import (
 	get_leave_balance_on,
 	get_leaves_for_period,
 )
 
+Filters = frappe._dict
 
-def execute(filters=None):
+def execute(filters: Filters = None) -> Tuple:
 	if filters.to_date <= filters.from_date:
 		frappe.throw(_('"From Date" can not be greater than or equal to "To Date"'))
 
@@ -23,8 +26,9 @@
 	charts = get_chart_data(data)
 	return columns, data, None, charts
 
-def get_columns():
-	columns = [{
+
+def get_columns() -> List[Dict]:
+	return [{
 		'label': _('Leave Type'),
 		'fieldtype': 'Link',
 		'fieldname': 'leave_type',
@@ -46,32 +50,31 @@
 		'label': _('Opening Balance'),
 		'fieldtype': 'float',
 		'fieldname': 'opening_balance',
-		'width': 130,
+		'width': 150,
 	}, {
-		'label': _('Leave Allocated'),
+		'label': _('New Leave(s) Allocated'),
 		'fieldtype': 'float',
 		'fieldname': 'leaves_allocated',
-		'width': 130,
+		'width': 200,
 	}, {
-		'label': _('Leave Taken'),
+		'label': _('Leave(s) Taken'),
 		'fieldtype': 'float',
 		'fieldname': 'leaves_taken',
-		'width': 130,
+		'width': 150,
 	}, {
-		'label': _('Leave Expired'),
+		'label': _('Leave(s) Expired'),
 		'fieldtype': 'float',
 		'fieldname': 'leaves_expired',
-		'width': 130,
+		'width': 150,
 	}, {
 		'label': _('Closing Balance'),
 		'fieldtype': 'float',
 		'fieldname': 'closing_balance',
-		'width': 130,
+		'width': 150,
 	}]
 
-	return columns
 
-def get_data(filters):
+def get_data(filters: Filters) -> List:
 	leave_types = frappe.db.get_list('Leave Type', pluck='name', order_by='name')
 	conditions = get_conditions(filters)
 
@@ -102,19 +105,18 @@
 				or ("HR Manager" in frappe.get_roles(user)):
 				if len(active_employees) > 1:
 					row = frappe._dict()
-				row.employee = employee.name,
+				row.employee = employee.name
 				row.employee_name = employee.employee_name
 
 				leaves_taken = get_leaves_for_period(employee.name, leave_type,
 					filters.from_date, filters.to_date) * -1
 
-				new_allocation, expired_leaves = get_allocated_and_expired_leaves(filters.from_date, filters.to_date, employee.name, leave_type)
-
-
-				opening = get_leave_balance_on(employee.name, leave_type, add_days(filters.from_date, -1)) #allocation boundary condition
+				new_allocation, expired_leaves, carry_forwarded_leaves = get_allocated_and_expired_leaves(
+					filters.from_date, filters.to_date, employee.name, leave_type)
+				opening = get_opening_balance(employee.name, leave_type, filters, carry_forwarded_leaves)
 
 				row.leaves_allocated = new_allocation
-				row.leaves_expired = expired_leaves - leaves_taken if expired_leaves - leaves_taken > 0 else 0
+				row.leaves_expired = expired_leaves
 				row.opening_balance = opening
 				row.leaves_taken = leaves_taken
 
@@ -125,7 +127,26 @@
 
 	return data
 
-def get_conditions(filters):
+
+def get_opening_balance(employee: str, leave_type: str, filters: Filters, carry_forwarded_leaves: float) -> float:
+	# allocation boundary condition
+	# opening balance is the closing leave balance 1 day before the filter start date
+	opening_balance_date = add_days(filters.from_date, -1)
+	allocation = get_previous_allocation(filters.from_date, leave_type, employee)
+
+	if allocation and allocation.get("to_date") and opening_balance_date and \
+		getdate(allocation.get("to_date")) == getdate(opening_balance_date):
+		# if opening balance date is same as the previous allocation's expiry
+		# then opening balance should only consider carry forwarded leaves
+		opening_balance = carry_forwarded_leaves
+	else:
+		# else directly get leave balance on the previous day
+		opening_balance = get_leave_balance_on(employee, leave_type, opening_balance_date)
+
+	return opening_balance
+
+
+def get_conditions(filters: Filters) -> Dict:
 	conditions={
 		'status': 'Active',
 	}
@@ -140,29 +161,26 @@
 
 	return conditions
 
-def get_department_leave_approver_map(department=None):
 
+def get_department_leave_approver_map(department: str = None):
 	# get current department and all its child
 	department_list = frappe.get_list('Department',
-						filters={
-							'disabled': 0
-						},
-						or_filters={
-							'name': department,
-							'parent_department': department
-						},
-						fields=['name'],
-						pluck='name'
-					)
+		filters={'disabled': 0},
+		or_filters={
+			'name': department,
+			'parent_department': department
+		},
+		pluck='name'
+	)
 	# retrieve approvers list from current department and from its subsequent child departments
 	approver_list = frappe.get_all('Department Approver',
-						filters={
-							'parentfield': 'leave_approvers',
-							'parent': ('in', department_list)
-						},
-						fields=['parent', 'approver'],
-						as_list=1
-					)
+		filters={
+			'parentfield': 'leave_approvers',
+			'parent': ('in', department_list)
+		},
+		fields=['parent', 'approver'],
+		as_list=True
+	)
 
 	approvers = {}
 
@@ -171,41 +189,61 @@
 
 	return approvers
 
-def get_allocated_and_expired_leaves(from_date, to_date, employee, leave_type):
 
-	from frappe.utils import getdate
-
+def get_allocated_and_expired_leaves(from_date: str, to_date: str, employee: str, leave_type: str) -> Tuple[float, float, float]:
 	new_allocation = 0
 	expired_leaves = 0
+	carry_forwarded_leaves = 0
 
-	records= frappe.db.sql("""
-		SELECT
-			employee, leave_type, from_date, to_date, leaves, transaction_name,
-			transaction_type, is_carry_forward, is_expired
-		FROM `tabLeave Ledger Entry`
-		WHERE employee=%(employee)s AND leave_type=%(leave_type)s
-			AND docstatus=1
-			AND transaction_type = 'Leave Allocation'
-			AND (from_date between %(from_date)s AND %(to_date)s
-				OR to_date between %(from_date)s AND %(to_date)s
-				OR (from_date < %(from_date)s AND to_date > %(to_date)s))
-	""", {
-		"from_date": from_date,
-		"to_date": to_date,
-		"employee": employee,
-		"leave_type": leave_type
-	}, as_dict=1)
+	records = get_leave_ledger_entries(from_date, to_date, employee, leave_type)
 
 	for record in records:
+		# new allocation records with `is_expired=1` are created when leave expires
+		# these new records should not be considered, else it leads to negative leave balance
+		if record.is_expired:
+			continue
+
 		if record.to_date < getdate(to_date):
+			# leave allocations ending before to_date, reduce leaves taken within that period
+			# since they are already used, they won't expire
 			expired_leaves += record.leaves
+			expired_leaves += get_leaves_for_period(employee, leave_type,
+					record.from_date, record.to_date)
 
 		if record.from_date >= getdate(from_date):
-			new_allocation += record.leaves
+			if record.is_carry_forward:
+				carry_forwarded_leaves += record.leaves
+			else:
+				new_allocation += record.leaves
 
-	return new_allocation, expired_leaves
+	return new_allocation, expired_leaves, carry_forwarded_leaves
 
-def get_chart_data(data):
+
+def get_leave_ledger_entries(from_date: str, to_date: str, employee: str, leave_type: str) -> List[Dict]:
+	ledger = frappe.qb.DocType('Leave Ledger Entry')
+	records = (
+		frappe.qb.from_(ledger)
+		.select(
+			ledger.employee, ledger.leave_type, ledger.from_date, ledger.to_date,
+			ledger.leaves, ledger.transaction_name, ledger.transaction_type,
+			ledger.is_carry_forward, ledger.is_expired
+		).where(
+			(ledger.docstatus == 1)
+			& (ledger.transaction_type == 'Leave Allocation')
+			& (ledger.employee == employee)
+			& (ledger.leave_type == leave_type)
+			& (
+				(ledger.from_date[from_date: to_date])
+				| (ledger.to_date[from_date: to_date])
+				| ((ledger.from_date < from_date) & (ledger.to_date > to_date))
+			)
+		)
+	).run(as_dict=True)
+
+	return records
+
+
+def get_chart_data(data: List) -> Dict:
 	labels = []
 	datasets = []
 	employee_data = data
@@ -224,7 +262,8 @@
 
 	return chart
 
-def get_dataset_for_chart(employee_data, datasets, labels):
+
+def get_dataset_for_chart(employee_data: List, datasets: List, labels: List) -> List:
 	leaves = []
 	employee_data = sorted(employee_data, key=lambda k: k['employee_name'])
 
diff --git a/erpnext/hr/report/employee_leave_balance/test_employee_leave_balance.py b/erpnext/hr/report/employee_leave_balance/test_employee_leave_balance.py
new file mode 100644
index 0000000..b2ed72c
--- /dev/null
+++ b/erpnext/hr/report/employee_leave_balance/test_employee_leave_balance.py
@@ -0,0 +1,161 @@
+# Copyright (c) 2021, Frappe Technologies Pvt. Ltd. and Contributors
+# License: GNU General Public License v3. See license.txt
+
+
+import unittest
+
+import frappe
+from frappe.utils import add_days, add_months, flt, get_year_ending, get_year_start, getdate
+
+from erpnext.hr.doctype.employee.test_employee import make_employee
+from erpnext.hr.doctype.holiday_list.test_holiday_list import set_holiday_list
+from erpnext.hr.doctype.leave_application.test_leave_application import (
+	get_first_sunday,
+	make_allocation_record,
+)
+from erpnext.hr.doctype.leave_ledger_entry.leave_ledger_entry import process_expired_allocation
+from erpnext.hr.doctype.leave_type.test_leave_type import create_leave_type
+from erpnext.hr.report.employee_leave_balance.employee_leave_balance import execute
+from erpnext.payroll.doctype.salary_slip.test_salary_slip import (
+	make_holiday_list,
+	make_leave_application,
+)
+
+test_records = frappe.get_test_records('Leave Type')
+
+class TestEmployeeLeaveBalance(unittest.TestCase):
+	def setUp(self):
+		for dt in ['Leave Application', 'Leave Allocation', 'Salary Slip', 'Leave Ledger Entry', 'Leave Type']:
+			frappe.db.delete(dt)
+
+		frappe.set_user('Administrator')
+
+		self.employee_id = make_employee('test_emp_leave_balance@example.com', company='_Test Company')
+
+		self.date = getdate()
+		self.year_start = getdate(get_year_start(self.date))
+		self.mid_year = add_months(self.year_start, 6)
+		self.year_end = getdate(get_year_ending(self.date))
+
+		self.holiday_list = make_holiday_list('_Test Emp Balance Holiday List', self.year_start, self.year_end)
+
+	def tearDown(self):
+		frappe.db.rollback()
+
+	@set_holiday_list('_Test Emp Balance Holiday List', '_Test Company')
+	def test_employee_leave_balance(self):
+		frappe.get_doc(test_records[0]).insert()
+
+		# 5 leaves
+		allocation1 = make_allocation_record(employee=self.employee_id, from_date=add_days(self.year_start, -11),
+			to_date=add_days(self.year_start, -1), leaves=5)
+		# 30 leaves
+		allocation2 = make_allocation_record(employee=self.employee_id, from_date=self.year_start, to_date=self.year_end)
+		# expires 5 leaves
+		process_expired_allocation()
+
+		# 4 days leave
+		first_sunday = get_first_sunday(self.holiday_list, for_date=self.year_start)
+		leave_application = make_leave_application(self.employee_id, add_days(first_sunday, 1), add_days(first_sunday, 4), '_Test Leave Type')
+		leave_application.reload()
+
+		filters = frappe._dict({
+			'from_date': allocation1.from_date,
+			'to_date': allocation2.to_date,
+			'employee': self.employee_id
+		})
+
+		report = execute(filters)
+
+		expected_data = [{
+			'leave_type': '_Test Leave Type',
+			'employee': self.employee_id,
+			'employee_name': 'test_emp_leave_balance@example.com',
+			'leaves_allocated': flt(allocation1.new_leaves_allocated + allocation2.new_leaves_allocated),
+			'leaves_expired': flt(allocation1.new_leaves_allocated),
+			'opening_balance': flt(0),
+			'leaves_taken': flt(leave_application.total_leave_days),
+			'closing_balance': flt(allocation2.new_leaves_allocated - leave_application.total_leave_days),
+			'indent': 1
+		}]
+
+		self.assertEqual(report[1], expected_data)
+
+	@set_holiday_list('_Test Emp Balance Holiday List', '_Test Company')
+	def test_opening_balance_on_alloc_boundary_dates(self):
+		frappe.get_doc(test_records[0]).insert()
+
+		# 30 leaves allocated
+		allocation1 = make_allocation_record(employee=self.employee_id, from_date=self.year_start, to_date=self.year_end)
+		# 4 days leave application in the first allocation
+		first_sunday = get_first_sunday(self.holiday_list, for_date=self.year_start)
+		leave_application = make_leave_application(self.employee_id, add_days(first_sunday, 1), add_days(first_sunday, 4), '_Test Leave Type')
+		leave_application.reload()
+
+		# Case 1: opening balance for first alloc boundary
+		filters = frappe._dict({
+			'from_date': self.year_start,
+			'to_date': self.year_end,
+			'employee': self.employee_id
+		})
+		report = execute(filters)
+		self.assertEqual(report[1][0].opening_balance, 0)
+
+		# Case 2: opening balance after leave application date
+		filters = frappe._dict({
+			'from_date': add_days(leave_application.to_date, 1),
+			'to_date': self.year_end,
+			'employee': self.employee_id
+		})
+		report = execute(filters)
+		self.assertEqual(report[1][0].opening_balance, (allocation1.new_leaves_allocated - leave_application.total_leave_days))
+
+		# Case 3: leave balance shows actual balance and not consumption balance as per remaining days near alloc end date
+		# eg: 3 days left for alloc to end, leave balance should still be 26 and not 3
+		filters = frappe._dict({
+			'from_date': add_days(self.year_end, -3),
+			'to_date': self.year_end,
+			'employee': self.employee_id
+		})
+		report = execute(filters)
+		self.assertEqual(report[1][0].opening_balance, (allocation1.new_leaves_allocated - leave_application.total_leave_days))
+
+	@set_holiday_list('_Test Emp Balance Holiday List', '_Test Company')
+	def test_opening_balance_considers_carry_forwarded_leaves(self):
+		leave_type = create_leave_type(
+			leave_type_name="_Test_CF_leave_expiry",
+			is_carry_forward=1)
+		leave_type.insert()
+
+		# 30 leaves allocated for first half of the year
+		allocation1 = make_allocation_record(employee=self.employee_id, from_date=self.year_start,
+			to_date=self.mid_year, leave_type=leave_type.name)
+		# 4 days leave application in the first allocation
+		first_sunday = get_first_sunday(self.holiday_list, for_date=self.year_start)
+		leave_application = make_leave_application(self.employee_id, first_sunday, add_days(first_sunday, 3), leave_type.name)
+		leave_application.reload()
+		# 30 leaves allocated for second half of the year + carry forward leaves (26) from the previous allocation
+		allocation2 = make_allocation_record(employee=self.employee_id, from_date=add_days(self.mid_year, 1), to_date=self.year_end,
+			carry_forward=True, leave_type=leave_type.name)
+
+		# Case 1: carry forwarded leaves considered in opening balance for second alloc
+		filters = frappe._dict({
+			'from_date': add_days(self.mid_year, 1),
+			'to_date': self.year_end,
+			'employee': self.employee_id
+		})
+		report = execute(filters)
+		# available leaves from old alloc
+		opening_balance = allocation1.new_leaves_allocated - leave_application.total_leave_days
+		self.assertEqual(report[1][0].opening_balance, opening_balance)
+
+		# Case 2: opening balance one day after alloc boundary = carry forwarded leaves + new leaves alloc
+		filters = frappe._dict({
+			'from_date': add_days(self.mid_year, 2),
+			'to_date': self.year_end,
+			'employee': self.employee_id
+		})
+		report = execute(filters)
+		# available leaves from old alloc
+		opening_balance = allocation2.new_leaves_allocated + (allocation1.new_leaves_allocated - leave_application.total_leave_days)
+		self.assertEqual(report[1][0].opening_balance, opening_balance)
diff --git a/erpnext/hr/report/employee_leave_balance_summary/employee_leave_balance_summary.py b/erpnext/hr/report/employee_leave_balance_summary/employee_leave_balance_summary.py
index 71c18bb..eee2eb8 100644
--- a/erpnext/hr/report/employee_leave_balance_summary/employee_leave_balance_summary.py
+++ b/erpnext/hr/report/employee_leave_balance_summary/employee_leave_balance_summary.py
@@ -12,6 +12,7 @@
 
 
 def execute(filters=None):
+	filters = frappe._dict(filters or {})
 	leave_types = frappe.db.sql_list("select name from `tabLeave Type` order by name asc")
 
 	columns = get_columns(leave_types)
diff --git a/erpnext/hr/report/employee_leave_balance_summary/test_employee_leave_balance_summary.py b/erpnext/hr/report/employee_leave_balance_summary/test_employee_leave_balance_summary.py
new file mode 100644
index 0000000..9b953de
--- /dev/null
+++ b/erpnext/hr/report/employee_leave_balance_summary/test_employee_leave_balance_summary.py
@@ -0,0 +1,117 @@
+# Copyright (c) 2021, Frappe Technologies Pvt. Ltd. and Contributors
+# License: GNU General Public License v3. See license.txt
+
+
+import unittest
+
+import frappe
+from frappe.utils import add_days, flt, get_year_ending, get_year_start, getdate
+
+from erpnext.hr.doctype.employee.test_employee import make_employee
+from erpnext.hr.doctype.holiday_list.test_holiday_list import set_holiday_list
+from erpnext.hr.doctype.leave_application.test_leave_application import (
+	get_first_sunday,
+	make_allocation_record,
+)
+from erpnext.hr.doctype.leave_ledger_entry.leave_ledger_entry import process_expired_allocation
+from erpnext.hr.report.employee_leave_balance_summary.employee_leave_balance_summary import execute
+from erpnext.payroll.doctype.salary_slip.test_salary_slip import (
+	make_holiday_list,
+	make_leave_application,
+)
+
+test_records = frappe.get_test_records('Leave Type')
+
+class TestEmployeeLeaveBalance(unittest.TestCase):
+	def setUp(self):
+		for dt in ['Leave Application', 'Leave Allocation', 'Salary Slip', 'Leave Ledger Entry', 'Leave Type']:
+			frappe.db.delete(dt)
+
+		frappe.set_user('Administrator')
+
+		self.employee_id = make_employee('test_emp_leave_balance@example.com', company='_Test Company')
+		self.employee_id = make_employee('test_emp_leave_balance@example.com', company='_Test Company')
+
+		self.date = getdate()
+		self.year_start = getdate(get_year_start(self.date))
+		self.year_end = getdate(get_year_ending(self.date))
+
+		self.holiday_list = make_holiday_list('_Test Emp Balance Holiday List', self.year_start, self.year_end)
+
+	def tearDown(self):
+		frappe.db.rollback()
+
+	@set_holiday_list('_Test Emp Balance Holiday List', '_Test Company')
+	def test_employee_leave_balance_summary(self):
+		frappe.get_doc(test_records[0]).insert()
+
+		# 5 leaves
+		allocation1 = make_allocation_record(employee=self.employee_id, from_date=add_days(self.year_start, -11),
+			to_date=add_days(self.year_start, -1), leaves=5)
+		# 30 leaves
+		allocation2 = make_allocation_record(employee=self.employee_id, from_date=self.year_start, to_date=self.year_end)
+
+		# 2 days leave within the first allocation
+		leave_application1 = make_leave_application(self.employee_id, add_days(self.year_start, -11), add_days(self.year_start, -10),
+			'_Test Leave Type')
+		leave_application1.reload()
+
+		# expires 3 leaves
+		process_expired_allocation()
+
+		# 4 days leave within the second allocation
+		first_sunday = get_first_sunday(self.holiday_list, for_date=self.year_start)
+		leave_application2 = make_leave_application(self.employee_id, add_days(first_sunday, 1), add_days(first_sunday, 4), '_Test Leave Type')
+		leave_application2.reload()
+
+		filters = {
+			'date': self.date,
+			'company': '_Test Company',
+			'employee': self.employee_id
+		}
+
+		report = execute(filters)
+
+		expected_data = [[
+			self.employee_id,
+			'test_emp_leave_balance@example.com',
+			frappe.db.get_value('Employee', self.employee_id, 'department'),
+			flt(
+				allocation1.new_leaves_allocated # allocated = 5
+				+ allocation2.new_leaves_allocated # allocated = 30
+				- leave_application1.total_leave_days # leaves taken in the 1st alloc = 2
+				- (allocation1.new_leaves_allocated - leave_application1.total_leave_days) # leaves expired from 1st alloc = 3
+				- leave_application2.total_leave_days # leaves taken in the 2nd alloc = 4
+			)
+		]]
+
+		self.assertEqual(report[1], expected_data)
+
+	@set_holiday_list('_Test Emp Balance Holiday List', '_Test Company')
+	def test_get_leave_balance_near_alloc_expiry(self):
+		frappe.get_doc(test_records[0]).insert()
+
+		# 30 leaves allocated
+		allocation = make_allocation_record(employee=self.employee_id, from_date=self.year_start, to_date=self.year_end)
+		# 4 days leave application in the first allocation
+		first_sunday = get_first_sunday(self.holiday_list, for_date=self.year_start)
+		leave_application = make_leave_application(self.employee_id, add_days(first_sunday, 1), add_days(first_sunday, 4), '_Test Leave Type')
+		leave_application.reload()
+
+		# Leave balance should show actual balance, and not "consumption balance as per remaining days", near alloc end date
+		# eg: 3 days left for alloc to end, leave balance should still be 26 and not 3
+		filters = {
+			'date': add_days(self.year_end, -3),
+			'company': '_Test Company',
+			'employee': self.employee_id
+		}
+		report = execute(filters)
+
+		expected_data = [[
+			self.employee_id,
+			'test_emp_leave_balance@example.com',
+			frappe.db.get_value('Employee', self.employee_id, 'department'),
+			flt(allocation.new_leaves_allocated - leave_application.total_leave_days)
+		]]
+
+		self.assertEqual(report[1], expected_data)
diff --git a/erpnext/payroll/doctype/salary_slip/salary_slip.py b/erpnext/payroll/doctype/salary_slip/salary_slip.py
index b44dbb9..181a2b5 100644
--- a/erpnext/payroll/doctype/salary_slip/salary_slip.py
+++ b/erpnext/payroll/doctype/salary_slip/salary_slip.py
@@ -1393,7 +1393,7 @@
 					'total_allocated_leaves': flt(leave_values.get('total_leaves')),
 					'expired_leaves': flt(leave_values.get('expired_leaves')),
 					'used_leaves': flt(leave_values.get('leaves_taken')),
-					'pending_leaves': flt(leave_values.get('pending_leaves')),
+					'pending_leaves': flt(leave_values.get('leaves_pending_approval')),
 					'available_leaves': flt(leave_values.get('remaining_leaves'))
 				})
 
diff --git a/erpnext/payroll/doctype/salary_slip/test_salary_slip.py b/erpnext/payroll/doctype/salary_slip/test_salary_slip.py
index fe15f2d..ebad3cb 100644
--- a/erpnext/payroll/doctype/salary_slip/test_salary_slip.py
+++ b/erpnext/payroll/doctype/salary_slip/test_salary_slip.py
@@ -1057,7 +1057,7 @@
 	}).submit()
 	return salary_date
 
-def make_leave_application(employee, from_date, to_date, leave_type, company=None):
+def make_leave_application(employee, from_date, to_date, leave_type, company=None, submit=True):
 	leave_application = frappe.get_doc(dict(
 		doctype = 'Leave Application',
 		employee = employee,
@@ -1065,11 +1065,12 @@
 		from_date = from_date,
 		to_date = to_date,
 		company = company or erpnext.get_default_company() or "_Test Company",
-		docstatus = 1,
 		status = "Approved",
 		leave_approver = 'test@example.com'
-	))
-	leave_application.submit()
+	)).insert()
+
+	if submit:
+		leave_application.submit()
 
 	return leave_application
 
@@ -1087,15 +1088,16 @@
 	frappe.db.set_value('HR Settings', None, 'leave_status_notification_template', None)
 	frappe.db.set_value('HR Settings', None, 'leave_approval_notification_template', None)
 
-def make_holiday_list(holiday_list_name=None):
+def make_holiday_list(list_name=None, from_date=None, to_date=None):
 	fiscal_year = get_fiscal_year(nowdate(), company=erpnext.get_default_company())
-	holiday_list = frappe.db.exists("Holiday List", holiday_list_name or "Salary Slip Test Holiday List")
+	name = list_name or "Salary Slip Test Holiday List"
+	holiday_list = frappe.db.exists("Holiday List", name)
 	if not holiday_list:
 		holiday_list = frappe.get_doc({
 			"doctype": "Holiday List",
-			"holiday_list_name": holiday_list_name or "Salary Slip Test Holiday List",
-			"from_date": fiscal_year[1],
-			"to_date": fiscal_year[2],
+			"holiday_list_name": name,
+			"from_date": from_date or fiscal_year[1],
+			"to_date": to_date or fiscal_year[2],
 			"weekly_off": "Sunday"
 		}).insert()
 		holiday_list.get_weekly_off_dates()
diff --git a/erpnext/payroll/doctype/salary_slip_leave/salary_slip_leave.json b/erpnext/payroll/doctype/salary_slip_leave/salary_slip_leave.json
index 7ac453b..60ed453 100644
--- a/erpnext/payroll/doctype/salary_slip_leave/salary_slip_leave.json
+++ b/erpnext/payroll/doctype/salary_slip_leave/salary_slip_leave.json
@@ -26,7 +26,7 @@
    "fieldname": "total_allocated_leaves",
    "fieldtype": "Float",
    "in_list_view": 1,
-   "label": "Total Allocated Leave",
+   "label": "Total Allocated Leave(s)",
    "no_copy": 1,
    "read_only": 1
   },
@@ -34,7 +34,7 @@
    "fieldname": "expired_leaves",
    "fieldtype": "Float",
    "in_list_view": 1,
-   "label": "Expired Leave",
+   "label": "Expired Leave(s)",
    "no_copy": 1,
    "read_only": 1
   },
@@ -42,7 +42,7 @@
    "fieldname": "used_leaves",
    "fieldtype": "Float",
    "in_list_view": 1,
-   "label": "Used Leave",
+   "label": "Used Leave(s)",
    "no_copy": 1,
    "read_only": 1
   },
@@ -50,7 +50,7 @@
    "fieldname": "pending_leaves",
    "fieldtype": "Float",
    "in_list_view": 1,
-   "label": "Pending Leave",
+   "label": "Leave(s) Pending Approval",
    "no_copy": 1,
    "read_only": 1
   },
@@ -58,7 +58,7 @@
    "fieldname": "available_leaves",
    "fieldtype": "Float",
    "in_list_view": 1,
-   "label": "Available Leave",
+   "label": "Available Leave(s)",
    "no_copy": 1,
    "read_only": 1
   }
@@ -66,7 +66,7 @@
  "index_web_pages_for_search": 1,
  "istable": 1,
  "links": [],
- "modified": "2021-02-19 10:47:48.546724",
+ "modified": "2022-02-28 14:01:32.327204",
  "modified_by": "Administrator",
  "module": "Payroll",
  "name": "Salary Slip Leave",
@@ -74,5 +74,6 @@
  "permissions": [],
  "sort_field": "modified",
  "sort_order": "DESC",
+ "states": [],
  "track_changes": 1
 }
\ No newline at end of file