From a5c21c40ad6ba638ee0a16ff92f25655fc0d6fe6 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sat, 20 Jun 2026 04:11:24 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20dictionary=20ini?=
 =?UTF-8?q?tialization=20in=20SysctlJournal.swift=20using=20reduce(into:)?=
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Co-authored-by: acebytes <2820910+acebytes@users.noreply.github.com>
---
 .jules/bolt.md                                |  4 ++++
 Sources/CacheoutHelperLib/SysctlJournal.swift | 21 ++++++++-----------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/.jules/bolt.md b/.jules/bolt.md
index 749e609..ed3edb1 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -126,3 +126,7 @@ If your candidate site already uses any of these, the issue is fixed.
 ## 2025-04-13 - Loop Filtering and Intermediate Allocations
 **Learning:** In Swift, using `.filter` before a `for` loop eagerly allocates a new intermediate array, causing unnecessary memory churn and processing overhead, especially during frequent operations like system monitoring.
 **Action:** Use `for ... where` clauses instead of eagerly filtering the collection prior to the loop (e.g., `for item in array where condition { ... }`). This prevents the allocation of intermediate arrays and improves efficiency.
+
+## 2025-05-15 - Array Materialization via sorted() on Lazy Sequences
+**Learning:** `LazyFilterSequence` does not have a custom `sorted()` implementation. Calling `sorted()` on a `LazyFilterSequence` relies on the default `Sequence` extension, which completely consumes the sequence and materializes it into an array immediately. While chaining `.lazy.filter` before `.sorted()` avoids allocating a separate intermediate array just for the filtered results, `sorted()` itself forces array materialization regardless. Adding `.lazy` specifically *just* before `.sorted()` creates confusion because it suggests the sort operation itself is lazy (which is impossible, sorting requires the whole collection). The codebase considers `.lazy.filter.sorted` an anti-pattern.
+**Action:** Do not propose adding `.lazy` before `.sorted()`. Ensure `.lazy` is only proposed when preceding operations that natively support lazy consumption like `.reduce`, `.count`, `.first`, `.contains`, or lazy `prefix`.
diff --git a/Sources/CacheoutHelperLib/SysctlJournal.swift b/Sources/CacheoutHelperLib/SysctlJournal.swift
index 07e9a53..65fe175 100644
--- a/Sources/CacheoutHelperLib/SysctlJournal.swift
+++ b/Sources/CacheoutHelperLib/SysctlJournal.swift
@@ -360,15 +360,13 @@ public final class SysctlJournal {
     /// `rollbackAll()` does not restore an intermediate value.
     private func revertStaleEntries() {
         let now = Date()
-        var firstStaleIndex: [String: Int] = [:]
-
         // Identify stale, un-rolled-back entries.
-        for i in state.entries.indices {
-            guard !state.entries[i].rolledBack else { continue }
+        let firstStaleIndex: [String: Int] = state.entries.indices.reduce(into: [:]) { dict, i in
+            guard !state.entries[i].rolledBack else { return }
             let age = now.timeIntervalSince(state.entries[i].timestamp)
-            guard age > Self.maxEntryAge else { continue }
-            if firstStaleIndex[state.entries[i].name] == nil {
-                firstStaleIndex[state.entries[i].name] = i
+            guard age > Self.maxEntryAge else { return }
+            if dict[state.entries[i].name] == nil {
+                dict[state.entries[i].name] = i
             }
         }
 
@@ -426,11 +424,10 @@ public final class SysctlJournal {
     @discardableResult
     private func performRollback() -> Bool {
         // Collect the first un-rolled-back entry per sysctl name.
-        var firstEntryIndex: [String: Int] = [:]
-        for i in state.entries.indices {
-            guard !state.entries[i].rolledBack else { continue }
-            if firstEntryIndex[state.entries[i].name] == nil {
-                firstEntryIndex[state.entries[i].name] = i
+        let firstEntryIndex: [String: Int] = state.entries.indices.reduce(into: [:]) { dict, i in
+            guard !state.entries[i].rolledBack else { return }
+            if dict[state.entries[i].name] == nil {
+                dict[state.entries[i].name] = i
             }
         }