From 5052a460b4b36bdc2517bd18470d97534d78ad94 Mon Sep 17 00:00:00 2001
From: Lukas Wirth <lukas@zed.dev>
Date: Thu, 20 Nov 2025 08:12:50 +0100
Subject: [PATCH] vim: Fix increment panicking due to invalid utf8 offsets
 (#43101)

Fixes ZED-3ER

Release Notes:

- Fixed a panic when using vim increment on a multibyte character
---
 crates/vim/src/normal/increment.rs | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/crates/vim/src/normal/increment.rs b/crates/vim/src/normal/increment.rs
index a6a76b22aa16d6fd774dc32a8b4988804ad8e42c..d9ef32deba5a3beb530d9ee42e2a6254df8c253b 100644
--- a/crates/vim/src/normal/increment.rs
+++ b/crates/vim/src/normal/increment.rs
@@ -210,12 +210,12 @@ fn find_target(
         .map_or(false, |ch| ch.is_ascii_hexdigit());
     let mut pre_char = String::new();
 
+    let next_offset = offset
+        + snapshot
+            .chars_at(start_offset)
+            .next()
+            .map_or(0, |ch| ch.len_utf8());
     // Backward scan to find the start of the number, but stop at start_offset
-    let next_offset = if offset < snapshot.len() {
-        offset + 1usize
-    } else {
-        offset
-    };
     for ch in snapshot.reversed_chars_at(next_offset) {
         // Search boundaries
         if offset.0 == 0 || ch.is_whitespace() || (need_range && offset <= start_offset) {
@@ -823,6 +823,14 @@ mod test {
         cx.set_state("trueˇ 1 2 3", Mode::Normal);
         cx.simulate_keystrokes("ctrl-a");
         cx.assert_state("true ˇ2 2 3", Mode::Normal);
+
+        cx.set_state("falseˇ", Mode::Normal);
+        cx.simulate_keystrokes("ctrl-a");
+        cx.assert_state("truˇe", Mode::Normal);
+
+        cx.set_state("⚡️ˇ⚡️", Mode::Normal);
+        cx.simulate_keystrokes("ctrl-a");
+        cx.assert_state("⚡️ˇ⚡️", Mode::Normal);
     }
 
     #[gpui::test]