From 1f76b66ff9abdc8cbe903d34f5393e4ef787e6c8 Mon Sep 17 00:00:00 2001
From: alice <166900055+alicesaidhi@users.noreply.github.com>
Date: Sun, 18 Aug 2024 13:30:52 +0200
Subject: [PATCH] fix fragments in effects

---
 src/apply.luau |  3 ++-
 src/bind.luau  | 13 +++++++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/apply.luau b/src/apply.luau
index 13e8cab..0f4586e 100644
--- a/src/apply.luau
+++ b/src/apply.luau
@@ -11,6 +11,7 @@ local graph = require(script.Parent.graph)
 type Node<T> = graph.Node<T>
 
 type Array<V> = { V }
+type ArrayOrV<V> = {ArrayOrV<V>} | V
 type Map<K, V> = { [K]: V }
 
 local free_caches: {
@@ -124,7 +125,7 @@ local function apply<T>(instance: T & Instance, properties: { [unknown]: unknown
                 end    
             elseif type(property) == "number" then
                 if type(value) == "function" then
-                    bind.children(instance, value :: () -> Instance | Array<Instance>) -- bind children
+                    bind.children(instance, value :: () -> ArrayOrV<Instance>) -- bind children
                 elseif type(value) == "table" then
                     if is_action(value) then
                         table.insert(actions[(value :: any).priority], (value :: any).callback :: () -> ()) -- add action to buffer
diff --git a/src/bind.luau b/src/bind.luau
index dd34ce3..3a016a6 100644
--- a/src/bind.luau
+++ b/src/bind.luau
@@ -38,6 +38,7 @@ type ChildrenBinding = {
     children: () -> Instance | { Instance }
 }
 
+type ArrayOrV<V> = V | { V }
 local function update_children_effect(p: ChildrenBinding)
     local cur_children_set: { [Instance]: true } = p.cur_children_set -- cache of all children parented before update
     local new_child_set: { [Instance]: true } = p.new_children_set -- cache of all children parented after update
@@ -48,8 +49,14 @@ local function update_children_effect(p: ChildrenBinding)
         new_children = { new_children }
     end
 
-    if new_children then
-        for _, child in next, new_children :: { Instance } do
+    local function process_child(child: ArrayOrV<Instance>)
+        if type(child) == "table" then
+            for _, child in next, child do
+                process_child(child)
+            end
+        else
+            if new_child_set[child] then return end -- stops redundant reparenting
+
             new_child_set[child] = true -- record child set from this update
             if not cur_children_set[child] then
                 child.Parent = p.instance -- if child wasn't already parented then parent it
@@ -59,6 +66,8 @@ local function update_children_effect(p: ChildrenBinding)
         end
     end
 
+    process_child(new_children)
+
     for child in next, cur_children_set do
         child.Parent = nil -- unparent all children that weren't in the new children set
     end