From aa178981dcf0c47586493c764c93428ff9234377 Mon Sep 17 00:00:00 2001
From: Ukendio <ukendio@gmail.com>
Date: Thu, 10 Jul 2025 12:50:59 +0200
Subject: [PATCH] Hotfix archetype not being marked dead

---
 jecs.luau       | 17 ++++++++++----
 test/tests.luau | 60 ++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 72 insertions(+), 5 deletions(-)

diff --git a/jecs.luau b/jecs.luau
index cc909a6..8cf42d5 100755
--- a/jecs.luau
+++ b/jecs.luau
@@ -781,6 +781,7 @@ local function archetype_register(world: World, archetype: Archetype)
 	local archetype_id = archetype.id
 	local columns_map = archetype.columns_map
 	local columns = archetype.columns
+
 	for i, component_id in archetype.types do
 		local idr = id_record_ensure(world, component_id)
 		local is_tag = bit32.btest(idr.flags, ECS_ID_IS_TAG)
@@ -803,6 +804,10 @@ local function archetype_register(world: World, archetype: Archetype)
 			archetype_append_to_records(idr_t, archetype_id, columns_map, t, i, column)
 		end
 	end
+
+	world.archetype_index[archetype.type] = archetype
+	world.archetypes[archetype_id] = archetype
+	world.archetype_edges[archetype.id] = {} :: Map<Id, Archetype>
 end
 
 local function archetype_create(world: World, id_types: { Id }, ty, prev: i53?): Archetype
@@ -824,7 +829,7 @@ local function archetype_create(world: World, id_types: { Id }, ty, prev: i53?):
 		dead = false,
 	}
 
-	archetype_register(world, archetype)
+	archetype_register(world, archetype, false)
 
 	for id in columns_map do
 		local observer_list = find_observers(world, EcsOnArchetypeCreate, id)
@@ -838,9 +843,6 @@ local function archetype_create(world: World, id_types: { Id }, ty, prev: i53?):
 		end
 	end
 
-	world.archetype_index[ty] = archetype
-	world.archetypes[archetype_id] = archetype
-	world.archetype_edges[archetype.id] = {} :: Map<Id, Archetype>
 
 	return archetype
 end
@@ -1078,6 +1080,8 @@ local function archetype_destroy(world: World, archetype: Archetype)
 			end
 		end
 	end
+
+	archetype.dead = true
 end
 
 local function NOOP() end
@@ -2324,6 +2328,10 @@ local function world_new()
 				end
 				edge[id] = to
 			else
+				if to.dead then
+					archetype_register(world, to)
+					to.dead = false
+				end
 				idr = component_index[id]
 			end
 			if from == to then
@@ -2342,6 +2350,7 @@ local function world_new()
 			if on_add then
 				on_add(entity, id)
 			end
+
 			return
 		end
 		local to = archetype_traverse_add(world, id, from)
diff --git a/test/tests.luau b/test/tests.luau
index a899b01..0758d9f 100755
--- a/test/tests.luau
+++ b/test/tests.luau
@@ -24,6 +24,44 @@ type Id<T=unknown> = jecs.Id<T>
 local entity_visualiser = require("@tools/entity_visualiser")
 local dwi = entity_visualiser.stringify
 
+FOCUS()
+TEST("", function()
+	local world = jecs.world()
+	local data = world:component()
+	local relation = world:component()
+	world:add(relation, jecs.pair(jecs.OnDeleteTarget, jecs.Delete))
+
+	local e1 = world:entity()
+	local e2 = world:entity()
+	world:set(e2, data, 456)
+	world:add(e2, jecs.pair(relation, e1))
+	world:delete(e1)
+
+	local e1v1 = world:entity()
+	CHECK(ECS_ID(e1v1) == e1)
+	local e2v1 = world:entity()
+	CHECK(ECS_ID(e2v1) == e2)
+	world:set(e2v1, data, 456)
+
+	CHECK(world:contains(e1v1))
+	CHECK(not world:contains(e2))
+	CHECK(world:contains(e2v1))
+
+	local count = 0
+	for i,val in world:query(data):iter() do
+		count += 1
+	end
+	CHECK(count == 1)
+	count = 0
+	world:add(e2v1, jecs.pair(relation, e1v1))
+	CHECK(world:has(e2v1, jecs.pair(relation, e1v1)))
+
+	for i,val in world:query(data):iter() do
+		count += 1
+	end
+
+	CHECK(count==1)
+end)
 TEST("bulk", function()
 	local world = jecs.world()
 	local A = world:component()
@@ -885,7 +923,6 @@ TEST("world:each()", function()
 	end
 end)
 
-FOCUS()
 TEST("world:range()", function()
 
 	do CASE "spawn entity under min range"
@@ -1122,6 +1159,7 @@ end)
 
 TEST("world:query()", function()
 	local N = 2^8
+
 	do CASE "cached"
 		local world = jecs.world()
 		local Foo = world:component()
@@ -1158,6 +1196,26 @@ TEST("world:query()", function()
 		world:delete(Foo)
 		CHECK(#q:archetypes() == 0)
 	end
+
+	do CASE "3 components"
+		local world = jecs.world()
+		local A = world:component() :: jecs.Entity<boolean>
+		local B = world:component() :: jecs.Entity<boolean>
+		local C = world:component() :: jecs.Entity<boolean>
+		local e = world:entity()
+		world:set(e, A, true)
+		world:set(e, B, true)
+		world:set(e, C, true)
+		local q = world:query(A, B, C):cached()
+		local counter = 0
+		for x, a, b, c in q:iter() do
+			counter += 1
+			CHECK(a)
+			CHECK(b)
+			CHECK(c)
+		end
+		CHECK(counter == 1)
+	end
 	do CASE "multiple iter"
 		local world = jecs.world()
 		local A = world:component() :: jecs.Entity<string>