From d6706e1f0e7539fa658ac93e9285e4a19531fe72 Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Fri, 24 Apr 2020 15:31:32 +1000
Subject: [PATCH] handle changed sort field index

---
 rslib/src/media/check.rs           |  2 +-
 rslib/src/notes.rs                 | 13 ++++++++-----
 rslib/src/notetype/mod.rs          |  6 +++++-
 rslib/src/notetype/schemachange.rs | 17 ++++++++++++++---
 4 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/rslib/src/media/check.rs b/rslib/src/media/check.rs
index d250722c8..5f33471b3 100644
--- a/rslib/src/media/check.rs
+++ b/rslib/src/media/check.rs
@@ -404,7 +404,7 @@ where
                 &self.mgr.media_folder,
             )? {
                 // note was modified, needs saving
-                note.prepare_for_update(nt, usn)?;
+                note.prepare_for_update(nt, Some(usn))?;
                 self.ctx.storage.update_note(&note)?;
                 collection_modified = true;
             }
diff --git a/rslib/src/notes.rs b/rslib/src/notes.rs
index 05660dab1..dbfc78560 100644
--- a/rslib/src/notes.rs
+++ b/rslib/src/notes.rs
@@ -63,7 +63,8 @@ impl Note {
         Ok(())
     }
 
-    pub fn prepare_for_update(&mut self, nt: &NoteType, usn: Usn) -> Result<()> {
+    /// Prepare note for saving to the database. If usn is provided, mtime will be bumped.
+    pub fn prepare_for_update(&mut self, nt: &NoteType, usn: Option<Usn>) -> Result<()> {
         assert!(nt.id == self.ntid);
         if nt.fields.len() != self.fields.len() {
             return Err(AnkiError::invalid_input(format!(
@@ -87,8 +88,10 @@ impl Note {
         };
         self.sort_field = Some(sort_field.into());
         self.checksum = Some(checksum);
-        self.mtime = TimestampSecs::now();
-        self.usn = usn;
+        if let Some(usn) = usn {
+            self.mtime = TimestampSecs::now();
+            self.usn = usn;
+        }
         Ok(())
     }
 
@@ -190,7 +193,7 @@ impl Collection {
         did: DeckID,
     ) -> Result<()> {
         self.canonify_note_tags(note, ctx.usn)?;
-        note.prepare_for_update(&ctx.notetype, ctx.usn)?;
+        note.prepare_for_update(&ctx.notetype, Some(ctx.usn))?;
         self.storage.add_note(note)?;
         self.generate_cards_for_new_note(ctx, note, did)
     }
@@ -211,7 +214,7 @@ impl Collection {
         note: &mut Note,
     ) -> Result<()> {
         self.canonify_note_tags(note, ctx.usn)?;
-        note.prepare_for_update(ctx.notetype, ctx.usn)?;
+        note.prepare_for_update(ctx.notetype, Some(ctx.usn))?;
         self.generate_cards_for_existing_note(ctx, note)?;
         self.storage.update_note(note)?;
 
diff --git a/rslib/src/notetype/mod.rs b/rslib/src/notetype/mod.rs
index 6c39ca7b1..a7f06a857 100644
--- a/rslib/src/notetype/mod.rs
+++ b/rslib/src/notetype/mod.rs
@@ -328,7 +328,11 @@ impl Collection {
         }
         self.transact(None, |col| {
             if let Some(existing_notetype) = existing {
-                col.update_notes_for_changed_fields(nt, existing_notetype.fields.len())?;
+                col.update_notes_for_changed_fields(
+                    nt,
+                    existing_notetype.fields.len(),
+                    existing_notetype.config.sort_field_idx,
+                )?;
                 col.update_cards_for_changed_templates(nt, existing_notetype.templates.len())?;
             }
 
diff --git a/rslib/src/notetype/schemachange.rs b/rslib/src/notetype/schemachange.rs
index 43164f438..e8c843bc6 100644
--- a/rslib/src/notetype/schemachange.rs
+++ b/rslib/src/notetype/schemachange.rs
@@ -54,11 +54,22 @@ impl Collection {
         &mut self,
         nt: &NoteType,
         previous_field_count: usize,
+        previous_sort_idx: u32,
     ) -> Result<()> {
         let ords: Vec<_> = nt.fields.iter().map(|f| f.ord).collect();
         if !ords_changed(&ords, previous_field_count) {
-            // nothing to do
-            return Ok(());
+            if nt.config.sort_field_idx == previous_sort_idx {
+                // only need to update sort field
+                let nids = self.search_notes_only(&format!("mid:{}", nt.id))?;
+                for nid in nids {
+                    let mut note = self.storage.get_note(nid)?.unwrap();
+                    note.prepare_for_update(nt, None)?;
+                    self.storage.update_note(&note)?;
+                }
+            } else {
+                // nothing to do
+                return Ok(());
+            }
         }
 
         self.storage.set_schema_modified()?;
@@ -81,7 +92,7 @@ impl Collection {
                 })
                 .map(Into::into)
                 .collect();
-            note.prepare_for_update(nt, usn)?;
+            note.prepare_for_update(nt, Some(usn))?;
             self.storage.update_note(&note)?;
         }
         Ok(())