From ac1f1bd3dada5665679f659160b5c9bb22a00296 Mon Sep 17 00:00:00 2001
From: Gabriel Kaszewski <gabrielkaszewski@gmail.com>
Date: Wed, 8 Apr 2026 01:29:20 +0200
Subject: [PATCH] fix(domain): remove dead use_sharps param, handle Cb
 enharmonic

---
 crates/domain/src/note.rs | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/crates/domain/src/note.rs b/crates/domain/src/note.rs
index 79f0134..93cd244 100644
--- a/crates/domain/src/note.rs
+++ b/crates/domain/src/note.rs
@@ -14,7 +14,7 @@ impl Note {
         }
     }
 
-    pub fn from_semitone(s: u8, use_sharps: bool) -> Note {
+    pub fn from_semitone(s: u8) -> Note {
         match s % 12 {
             0 => Note::C, 1 => Note::CSharpDFlat, 2 => Note::D,
             3 => Note::DSharpEFlat, 4 => Note::E, 5 => Note::F,
@@ -66,12 +66,11 @@ impl Note {
     }
 
     fn sharp_of(root: Note) -> Note {
-        Note::from_semitone((root.semitone() + 1) % 12, true)
+        Note::from_semitone((root.semitone() + 1) % 12)
     }
 
     fn flat_of(root: Note) -> Option<Note> {
-        if root.semitone() == 0 { return None; } // Cb is unusual, skip
-        Some(Note::from_semitone((root.semitone() + 11) % 12, false))
+        Some(Note::from_semitone((root.semitone() + 11) % 12))
     }
 }
 
@@ -81,8 +80,13 @@ mod tests {
 
     #[test]
     fn semitone_roundtrip() {
-        assert_eq!(Note::from_semitone(Note::A.semitone(), true), Note::A);
-        assert_eq!(Note::from_semitone(Note::FSharpGFlat.semitone(), true), Note::FSharpGFlat);
+        assert_eq!(Note::from_semitone(Note::A.semitone()), Note::A);
+        assert_eq!(Note::from_semitone(Note::FSharpGFlat.semitone()), Note::FSharpGFlat);
+    }
+
+    #[test]
+    fn parse_cb_enharmonic() {
+        assert_eq!(Note::from_str("Cb"), Some(Note::B));
     }
 
     #[test]