From 88d65e65eb92c8e086bdbb7d938bbb44522caf6f Mon Sep 17 00:00:00 2001
From: iamcheeseman <dev@iamcheeseman.net>
Date: Fri, 13 Mar 2026 15:44:03 -0400
Subject: Fix crash when adding entities after comp removal

---
 src/ecs.lua | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

(limited to 'src/ecs.lua')

diff --git a/src/ecs.lua b/src/ecs.lua
index 373d338..a1dab27 100644
--- a/src/ecs.lua
+++ b/src/ecs.lua
@@ -83,9 +83,10 @@ local function remove_comp(ent, comp)
   local lastid = mask.dense[mask.size]
 
   mask.sparse[ent.id] = nil
-  mask.sparse[lastid] = index
-
-  mask.dense[index] = mask.dense[mask.size]
+  if ent.id ~= lastid then
+    mask.sparse[lastid] = index
+    mask.dense[index] = mask.dense[mask.size]
+  end
   mask.dense[mask.size] = nil
   mask.size = mask.size - 1
 end
-- 
cgit v1.3-2-g0d8e