From fcd9905291c02917410ff7c55542fd73e4b25e2d Mon Sep 17 00:00:00 2001
From: luukvbaal <luukvbaal@gmail.com>
Date: Tue, 23 Jan 2024 22:51:18 +0100
Subject: [PATCH] fix(sign): avoid deleting from sign map while looping over it
 (#27158)

---
 src/nvim/sign.c                  |  7 ++++++-
 test/functional/ui/sign_spec.lua | 12 +++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/nvim/sign.c b/src/nvim/sign.c
index b1a2d1ad08..dc09bcc5a0 100644
--- a/src/nvim/sign.c
+++ b/src/nvim/sign.c
@@ -1021,9 +1021,14 @@ static void sign_get_placed(buf_T *buf, linenr_T lnum, int id, const char *group
 void free_signs(void)
 {
   cstr_t name;
+  kvec_t(cstr_t) names = KV_INITIAL_VALUE;
   map_foreach_key(&sign_map, name, {
-    sign_undefine_by_name(name);
+    kv_push(names, name);
   });
+  for (size_t i = 0; i < kv_size(names); i++) {
+    sign_undefine_by_name(kv_A(names, i));
+  }
+  kv_destroy(names);
 }
 
 static enum {
diff --git a/test/functional/ui/sign_spec.lua b/test/functional/ui/sign_spec.lua
index af03bce4a0..847a918dc9 100644
--- a/test/functional/ui/sign_spec.lua
+++ b/test/functional/ui/sign_spec.lua
@@ -1,6 +1,7 @@
 local helpers = require('test.functional.helpers')(after_each)
 local Screen = require('test.functional.ui.screen')
-local clear, feed, exec, api = helpers.clear, helpers.feed, helpers.exec, helpers.api
+local api, clear, eq = helpers.api, helpers.clear, helpers.eq
+local eval, exec, feed = helpers.eval, helpers.exec, helpers.feed
 
 describe('Signs', function()
   local screen
@@ -565,4 +566,13 @@ describe('Signs', function()
                                                            |
     ]])
   end)
+
+  it('sign_undefine() frees all signs', function()
+    exec([[
+      sign define 1 text=1
+      sign define 2 text=2
+      call sign_undefine()
+    ]])
+    eq({}, eval('sign_getdefined()'))
+  end)
 end)