From 6e496b7a4a647db579ee0f3cf1f66883c1b91d15 Mon Sep 17 00:00:00 2001
From: Alex McLean <alex@slab.org>
Date: Sat, 27 Jul 2024 10:02:38 +0100
Subject: [PATCH] Fix loop at tactus (#1145)

* fix loopAt tactus
---
 packages/core/pattern.mjs           | 3 ++-
 packages/core/test/pattern.test.mjs | 5 +++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/packages/core/pattern.mjs b/packages/core/pattern.mjs
index 99f038e2..e4745368 100644
--- a/packages/core/pattern.mjs
+++ b/packages/core/pattern.mjs
@@ -2929,7 +2929,8 @@ export const splice = register(
 );
 
 export const { loopAt, loopat } = register(['loopAt', 'loopat'], function (factor, pat) {
-  return new Pattern((state) => _loopAt(factor, pat, state.controls._cps).query(state));
+  const tactus = pat.tactus ? pat.tactus.div(factor) : undefined;
+  return new Pattern((state) => _loopAt(factor, pat, state.controls._cps).query(state), tactus);
 });
 
 /**
diff --git a/packages/core/test/pattern.test.mjs b/packages/core/test/pattern.test.mjs
index 8c5a54ff..31ec4868 100644
--- a/packages/core/test/pattern.test.mjs
+++ b/packages/core/test/pattern.test.mjs
@@ -1248,4 +1248,9 @@ describe('Pattern', () => {
       );
     });
   });
+  describe('loopAt', () => {
+    it('maintains tactus', () => {
+      expect(s('bev').chop(8).loopAt(2).tactus).toStrictEqual(Fraction(4));
+    });
+  });
 });