From f975861891ae9cf6d6d4a21a4e52ed9f09fa15e0 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Tue, 7 May 2024 10:36:54 -0700
Subject: [PATCH] terminal: maintain dirty bits when rotating rows on clone

---
 src/terminal/PageList.zig | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/terminal/PageList.zig b/src/terminal/PageList.zig
index 158717359..d505465cf 100644
--- a/src/terminal/PageList.zig
+++ b/src/terminal/PageList.zig
@@ -473,6 +473,11 @@ pub fn clone(
             continue;
         }
 
+        // We want to maintain the dirty bits from the original page so
+        // instead of setting a range we grab the dirty bit and then
+        // set it on the new page in the new location.
+        var dirty = page.data.dirtyBitSet();
+
         // Kind of slow, we want to shift the rows up in the page up to
         // end and then resize down.
         const rows = page.data.rows.ptr(page.data.memory);
@@ -483,6 +488,7 @@ pub fn clone(
             const old_dst = dst.*;
             dst.* = src.*;
             src.* = old_dst;
+            dirty.setValue(i, dirty.isSet(i + chunk.start));
         }
         page.data.size.rows = @intCast(len);
         total_rows += len;