From 4df89c7c26c596e2e45947ecd2347bf46813a31b Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Sun, 23 Aug 2020 12:09:36 +1000
Subject: [PATCH] ensure we don't crash on a zero field notetype

---
 rslib/src/notes.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/rslib/src/notes.rs b/rslib/src/notes.rs
index 657b0750b..35a56d7a6 100644
--- a/rslib/src/notes.rs
+++ b/rslib/src/notes.rs
@@ -79,11 +79,12 @@ impl Note {
     /// Prepare note for saving to the database. Does not mark it as modified.
     pub fn prepare_for_update(&mut self, nt: &NoteType, normalize_text: bool) -> Result<()> {
         assert!(nt.id == self.ntid);
-        if nt.fields.len() != self.fields.len() {
+        let notetype_field_count = nt.fields.len().max(1);
+        if notetype_field_count != self.fields.len() {
             return Err(AnkiError::invalid_input(format!(
                 "note has {} fields, expected {}",
                 self.fields.len(),
-                nt.fields.len()
+                notetype_field_count
             )));
         }