fix: Batch scans get overwritten on the same row

erpnext/public/js/controllers/transaction.js

@@ -345,9 +345,112 @@ erpnext.TransactionController = class TransactionController extends erpnext.taxe
 	}
 
 	scan_barcode() {
-		let scan_barcode_field = this.frm.fields_dict["scan_barcode"];
+		let me = this;
 
-		let show_description = function(idx, exist = null) {
+		if(this.frm.doc.scan_barcode) {
+			frappe.call({
+				method: "erpnext.selling.page.point_of_sale.point_of_sale.search_for_serial_or_batch_or_barcode_number",
+				args: {
+					search_value: this.frm.doc.scan_barcode
+				}
+			}).then(r => {
+				const data = r && r.message;
+				if (!data || Object.keys(data).length === 0) {
+					frappe.show_alert({
+						message: __('Cannot find Item with this Barcode'),
+						indicator: 'red'
+					});
+					return;
+				}
+
+				me.modify_table_after_scan(data);
+			});
+		}
+		return false;
+	}
+
+	modify_table_after_scan(data) {
+		let scan_barcode_field = this.frm.fields_dict["scan_barcode"];
+		let cur_grid = this.frm.fields_dict.items.grid;
+		let row_to_modify = null;
+
+		// Check if batch is scanned and table has batch no field
+		let batch_no_scan = Boolean(data.batch_no) && frappe.meta.has_field(cur_grid.doctype, "batch_no");
+
+		if (batch_no_scan) {
+			let duplicate = this.check_duplicate_batch_scan(data.batch_no);
+			if (duplicate) {
+				scan_barcode_field.set_value('');
+				return;
+			}
+		} else {
+			// serial or barcode scan
+			row_to_modify = this.get_row_to_modify_on_scan(row_to_modify, data);
+		}
+
+		if (!row_to_modify || batch_no_scan) {
+			// add new row if new item scanned or batch is scanned
+			row_to_modify = frappe.model.add_child(this.frm.doc, cur_grid.doctype, 'items');
+		}
+
+		this.show_scan_message(row_to_modify.idx, row_to_modify.item_code);
+		this.set_scanned_values(row_to_modify, data, scan_barcode_field);
+	}
+
+	set_scanned_values(row_to_modify, data, scan_barcode_field) {
+		// increase qty and set scanned value and item in row
+		this.frm.from_barcode = this.frm.from_barcode ? this.frm.from_barcode + 1 : 1;
+		frappe.model.set_value(row_to_modify.doctype, row_to_modify.name, {
+			item_code: data.item_code,
+			qty: (row_to_modify.qty || 0) + 1
+		});
+
+		['serial_no', 'batch_no', 'barcode'].forEach(field => {
+			if (data[field] && frappe.meta.has_field(row_to_modify.doctype, field)) {
+				let is_serial_no = row_to_modify[field] && field === "serial_no";
+
+				let value = data[field];
+				if (is_serial_no) {
+					value = row_to_modify[field] + '\n' + data[field];
+				}
+
+				frappe.model.set_value(row_to_modify.doctype, row_to_modify.name, field, value);
+			}
+		});
+
+		scan_barcode_field.set_value('');
+		refresh_field("items");
+	}
+
+	get_row_to_modify_on_scan(row_to_modify, data) {
+		// get an existing item row to increment or blank row to modify
+		const existing_item_row = this.frm.doc.items.find(d => d.item_code === data.item_code);
+		const blank_item_row = this.frm.doc.items.find(d => !d.item_code);
+
+		if (existing_item_row) {
+			row_to_modify = existing_item_row;
+		} else if (blank_item_row) {
+			row_to_modify = blank_item_row;
+		}
+
+		return row_to_modify;
+	}
+
+	check_duplicate_batch_scan(batch_no) {
+		// ignore scan if batch already exists in table
+		const existing_batch_row = this.frm.doc.items.find(d => d.batch_no === batch_no);
+
+		if (existing_batch_row) {
+			frappe.show_alert({
+				message: __('Batch {0} already added', [batch_no]),
+				indicator: 'orange'
+			});
+			return true;
+		}
+		return false;
+	}
+
+	show_scan_message (idx, exist = null) {
 		if (exist) {
 			frappe.show_alert({
 				message: __('Row #{0}: Qty increased by 1', [idx]),
@@ -361,63 +464,6 @@ erpnext.TransactionController = class TransactionController extends erpnext.taxe
 		}
 	}
 
-		if(this.frm.doc.scan_barcode) {
-			frappe.call({
-				method: "erpnext.selling.page.point_of_sale.point_of_sale.search_for_serial_or_batch_or_barcode_number",
-				args: { search_value: this.frm.doc.scan_barcode }
-			}).then(r => {
-				const data = r && r.message;
-				if (!data || Object.keys(data).length === 0) {
-					frappe.show_alert({
-						message: __('Cannot find Item with this Barcode'),
-						indicator: 'red'
-					});
-					return;
-				}
-
-				let cur_grid = this.frm.fields_dict.items.grid;
-
-				let row_to_modify = null;
-				const existing_item_row = this.frm.doc.items.find(d => d.item_code === data.item_code);
-				const blank_item_row = this.frm.doc.items.find(d => !d.item_code);
-
-				if (existing_item_row) {
-					row_to_modify = existing_item_row;
-				} else if (blank_item_row) {
-					row_to_modify = blank_item_row;
-				}
-
-				if (!row_to_modify) {
-					// add new row
-					row_to_modify = frappe.model.add_child(this.frm.doc, cur_grid.doctype, 'items');
-				}
-
-				show_description(row_to_modify.idx, row_to_modify.item_code);
-
-				this.frm.from_barcode = this.frm.from_barcode ? this.frm.from_barcode + 1 : 1;
-				frappe.model.set_value(row_to_modify.doctype, row_to_modify.name, {
-					item_code: data.item_code,
-					qty: (row_to_modify.qty || 0) + 1
-				});
-
-				['serial_no', 'batch_no', 'barcode'].forEach(field => {
-					if (data[field] && frappe.meta.has_field(row_to_modify.doctype, field)) {
-
-						let value = (row_to_modify[field] && field === "serial_no")
-							? row_to_modify[field] + '\n' + data[field] : data[field];
-
-						frappe.model.set_value(row_to_modify.doctype,
-							row_to_modify.name, field, value);
-					}
-				});
-
-				scan_barcode_field.set_value('');
-				refresh_field("items");
-			});
-		}
-		return false;
-	}
-
 	apply_default_taxes() {
 		var me = this;
 		var taxes_and_charges_field = frappe.meta.get_docfield(me.frm.doc.doctype, "taxes_and_charges",