From 62ed1e8180a5daf1fcd354c5b43924def93a37e5 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Mon, 6 Apr 2026 05:15:46 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Batch=20@Published=20array?=
 =?UTF-8?q?=20updates=20in=20CacheoutViewModel?=
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Batch array updates by using `map` instead of `for` loop property access.
This avoids triggering SwiftUI re-renders for every single item mutation, drastically improving responsiveness when checking/unchecking items, especially node_modules which can contain many items.

Co-authored-by: acebytes <2820910+acebytes@users.noreply.github.com>
---
 .jules/bolt.md                                |  3 ++
 .../ViewModels/CacheoutViewModel.swift        | 34 ++++++++++++++-----
 2 files changed, 29 insertions(+), 8 deletions(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 0000000..2244bf6
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,3 @@
+## 2024-05-24 - Batching @Published Array Updates
+**Learning:** Mutating elements of a `@Published` array of structs in a `for` loop (e.g. `for i in array.indices { array[i].prop = val }`) inside an `ObservableObject` triggers a separate UI update for every single iteration, causing severe UI unresponsiveness and thrashing when dealing with many items (like `nodeModulesItems`).
+**Action:** Always use `.map` to create a new array and assign it back to the `@Published` property in a single operation, batching the UI updates.
diff --git a/Sources/Cacheout/ViewModels/CacheoutViewModel.swift b/Sources/Cacheout/ViewModels/CacheoutViewModel.swift
index 13a9811..ade61c9 100644
--- a/Sources/Cacheout/ViewModels/CacheoutViewModel.swift
+++ b/Sources/Cacheout/ViewModels/CacheoutViewModel.swift
@@ -172,14 +172,20 @@ class CacheoutViewModel: ObservableObject {
     }
 
     func selectAllSafe() {
-        for i in scanResults.indices where scanResults[i].category.riskLevel == .safe && !scanResults[i].isEmpty {
-            scanResults[i].isSelected = true
+        scanResults = scanResults.map { result in
+            var copy = result
+            if copy.category.riskLevel == .safe && !copy.isEmpty {
+                copy.isSelected = true
+            }
+            return copy
         }
     }
 
     func deselectAll() {
-        for i in scanResults.indices {
-            scanResults[i].isSelected = false
+        scanResults = scanResults.map { result in
+            var copy = result
+            copy.isSelected = false
+            return copy
         }
         deselectAllNodeModules()
     }
@@ -193,17 +199,29 @@ class CacheoutViewModel: ObservableObject {
     }
 
     func selectStaleNodeModules() {
-        for i in nodeModulesItems.indices where nodeModulesItems[i].isStale {
-            nodeModulesItems[i].isSelected = true
+        nodeModulesItems = nodeModulesItems.map { item in
+            var copy = item
+            if copy.isStale {
+                copy.isSelected = true
+            }
+            return copy
         }
     }
 
     func selectAllNodeModules() {
-        for i in nodeModulesItems.indices { nodeModulesItems[i].isSelected = true }
+        nodeModulesItems = nodeModulesItems.map { item in
+            var copy = item
+            copy.isSelected = true
+            return copy
+        }
     }
 
     func deselectAllNodeModules() {
-        for i in nodeModulesItems.indices { nodeModulesItems[i].isSelected = false }
+        nodeModulesItems = nodeModulesItems.map { item in
+            var copy = item
+            copy.isSelected = false
+            return copy
+        }
     }
 
     /// Menu bar label: show free GB in the tray