fix(selling): don't email cancelled proformas or copy their PDF

Address review findings:
- send_proforma_email rejects non-issued proformas, and the tab suppresses the
  action for cancelled rows, so a voided document can't be sent to a customer
- mark proforma_pdf as no_copy and disable amendment (a proforma is created
  only from a Sales Order), so a copied proforma can't carry the original's PDF
  and number

erpnext/public/js/sales_order_proforma.js

@@ -301,7 +301,13 @@ Object.assign(erpnext.proforma, {
 						{
 							icon: "mail",
 							label: __("Send Email"),
-							action: (row, refresh) => this.send_email(frm, row.name, refresh),
+							action: (row, refresh) => {
+								if (row.status === "Cancelled") {
+									frappe.msgprint(__("A cancelled Proforma Invoice cannot be emailed."));
+									return;
+								}
+								this.send_email(frm, row.name, refresh);
+							},
 						},
 					],
 				},

erpnext/selling/doctype/proforma_invoice/proforma_invoice.json

@@ -187,6 +187,7 @@
    "fieldname": "proforma_pdf",
    "fieldtype": "Attach",
    "label": "Proforma PDF",
+   "no_copy": 1,
    "read_only": 1
   },
   {
@@ -250,7 +251,6 @@
  "owner": "Administrator",
  "permissions": [
   {
-   "amend": 1,
    "cancel": 1,
    "create": 1,
    "delete": 1,
@@ -264,7 +264,6 @@
    "write": 1
   },
   {
-   "amend": 1,
    "cancel": 1,
    "create": 1,
    "delete": 1,

erpnext/selling/doctype/proforma_invoice/proforma_invoice.py

@@ -212,6 +212,8 @@ def _proforma_line(so_item, based_on: str, row: dict) -> dict | None:
 @frappe.whitelist()
 def send_proforma_email(proforma_name: str, recipients: str) -> None:
 	proforma = frappe.get_doc("Proforma Invoice", proforma_name)
+	if proforma.docstatus != 1:
+		frappe.throw(_("Only an issued Proforma Invoice can be emailed."))
 	if not proforma.proforma_pdf:
 		frappe.throw(_("This Proforma Invoice has no PDF to send."))
 

erpnext/selling/doctype/proforma_invoice/test_proforma_invoice.py

@@ -9,6 +9,7 @@ from frappe.utils import flt
 from erpnext.selling.doctype.proforma_invoice.proforma_invoice import (
 	get_sales_order_items,
 	make_proforma_invoice,
+	send_proforma_email,
 )
 from erpnext.selling.doctype.sales_order.test_sales_order import make_sales_order
 from erpnext.tests.utils import ERPNextTestSuite
@@ -144,6 +145,13 @@ class TestProformaInvoice(ERPNextTestSuite):
 			[(sales_order.items[0].name, 4)],
 		)
 
+	def test_cannot_email_cancelled_proforma(self):
+		sales_order = make_sales_order(qty=10)
+		proforma = self.create_proforma(sales_order, [(sales_order.items[0].name, 4)])
+		proforma.cancel()
+
+		self.assertRaises(frappe.ValidationError, send_proforma_email, proforma.name, "customer@example.com")
+
 	def test_requires_submitted_sales_order(self):
 		"""The server rejects a proforma against a draft Sales Order (the button is JS-gated only)."""
 		sales_order = make_sales_order(qty=10, do_not_submit=True)