feat: multi-select customer group in AR Report
diff --git a/erpnext/accounts/report/accounts_receivable/accounts_receivable.js b/erpnext/accounts/report/accounts_receivable/accounts_receivable.js
index 1073be0..393a6ff 100644
--- a/erpnext/accounts/report/accounts_receivable/accounts_receivable.js
+++ b/erpnext/accounts/report/accounts_receivable/accounts_receivable.js
@@ -114,10 +114,13 @@
 			"reqd": 1
 		},
 		{
-			"fieldname": "customer_group",
+			"fieldname":"customer_group",
 			"label": __("Customer Group"),
-			"fieldtype": "Link",
-			"options": "Customer Group"
+			"fieldtype": "MultiSelectList",
+			"options": "Customer Group",
+			get_data: function(txt) {
+				return frappe.db.get_link_options('Customer Group', txt);
+			}
 		},
 		{
 			"fieldname": "payment_terms_template",
diff --git a/erpnext/accounts/report/accounts_receivable/accounts_receivable.py b/erpnext/accounts/report/accounts_receivable/accounts_receivable.py
index b9c7a0b..dfe801c 100755
--- a/erpnext/accounts/report/accounts_receivable/accounts_receivable.py
+++ b/erpnext/accounts/report/accounts_receivable/accounts_receivable.py
@@ -823,7 +823,9 @@
 		self.customer = qb.DocType("Customer")
 
 		if self.filters.get("customer_group"):
-			self.get_hierarchical_filters("Customer Group", "customer_group")
+			groups = get_customer_group_with_children(self.filters.customer_group)
+			customers = qb.from_(self.customer).select(self.customer.name).where(self.customer['customer_group'].isin(groups))
+			self.qb_selection_filter.append(self.ple.party.isin(customers))
 
 		if self.filters.get("territory"):
 			self.get_hierarchical_filters("Territory", "territory")
@@ -1115,3 +1117,18 @@
 			.run()
 		)
 		self.err_journals = [x[0] for x in results] if results else []
+
+def get_customer_group_with_children(customer_groups):
+	if not isinstance(customer_groups, list):
+		customer_groups = [d.strip() for d in customer_groups.strip().split(",") if d]
+
+	all_customer_groups = []
+	for d in customer_groups:
+		if frappe.db.exists("Customer Group", d):
+			lft, rgt = frappe.db.get_value("Customer Group", d, ["lft", "rgt"])
+			children = frappe.get_all("Customer Group", filters={"lft": [">=", lft], "rgt": ["<=", rgt]})
+			all_customer_groups += [c.name for c in children]
+		else:
+			frappe.throw(_("Customer Group: {0} does not exist").format(d))
+
+	return list(set(all_customer_groups))