Creating a BOM from the Item connections

Becario · August 11, 2026, 3:08pm

When on the Item connections tab, if you click the plus to create a new BOM for the item, it will set the item as the Item to Manufacture and add as a component:

This doesn’t make any sense to me, as an item can’t be made using itself.

I’m using ERPNext v16.31.1

Becario · September 9, 2026, 1:01pm

I found what makes this happen, even if the why eludes me.

The behaviour comes from how make_new automatically fills in fields when creating a new document:

github.com/frappe/frappe

frappe/public/js/frappe/form/form.js

version-16


      
          	make_new(doctype) {
          		// make new doctype from the current form
          		// will handover to `make_methods` if defined
          		// or will create and match link fields
          		let me = this;
          		if (this.make_methods && this.make_methods[doctype]) {
          			return this.make_methods[doctype](this);
          		} else if (this.custom_make_buttons && this.custom_make_buttons[doctype]) {
          			this.custom_buttons[__(this.custom_make_buttons[doctype])].trigger("click");
          		} else {
          			frappe.model.with_doctype(doctype, function () {
          				let new_doc = frappe.model.get_new_doc(doctype, null, null, true);
          
          				// set link fields (if found)
          				me.set_link_field(doctype, new_doc);
          
          				frappe.ui.form.make_quick_entry(doctype, null, null, new_doc);
          				// frappe.set_route('Form', doctype, new_doc.name);
          			});
          		}
          	}

It will go through all the fields in the BOM document, and for any which are Link fields to Item, set them to the item. This includes the item field in the BOM Item child table, as it is set as required.