From 6ef780704cb659e09bf60ced66edfde0dbcdb649 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sat, 9 May 2026 21:36:43 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20[performance=20improvement]?=
 =?UTF-8?q?=20Avoid=20intermediate=20Vector=20allocations=20in=20xdk-build?=
 =?UTF-8?q?=20and=20xdk-lib?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Replaced string `.split("\n")` with character `.split('\n')` in `xdk-build/src/python.rs`.
- Removed intermediate `.collect::<Vec<&str>>().into_iter()` on string split in `xdk-build/src/python.rs`.
- Replaced `.collect::<Vec<_>>().join("")` with `.collect::<String>()` for String concatenation in `xdk-lib/src/casing.rs`.

Co-authored-by: cloudesize67-cmd <237356855+cloudesize67-cmd@users.noreply.github.com>
---
 .jules/bolt.md          |  3 +++
 xdk-build/src/python.rs | 16 ++++++----------
 xdk-lib/src/casing.rs   |  6 +-----
 3 files changed, 10 insertions(+), 15 deletions(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 00000000..dc40f3f4
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,3 @@
+## 2024-06-25 - [Rust Iterator Allocations]
+**Learning:** In Rust, avoid intermediate allocations by iterating directly over iterator sources (like `.split()`) rather than calling `.collect::<Vec<_>>().into_iter()`. Also, use character-based splits (e.g., `.split('\n')`) instead of string-based splits (e.g., `.split("\n")`) for single characters. Furthermore, when transforming and aggregating collections of strings, use `.collect::<String>()` instead of `.collect::<Vec<_>>().join("")` for string concatenation to prevent intermediate vector allocations.
+**Action:** When working with iterators and strings in Rust, check for intermediate allocations that can be avoided by directly using `collect::<String>()` or dropping `collect::<Vec<_>>().into_iter()` from iterator chains. Use `char` arguments for single-character string functions to enhance performance.
diff --git a/xdk-build/src/python.rs b/xdk-build/src/python.rs
index 1d15d6f0..c90da4f9 100644
--- a/xdk-build/src/python.rs
+++ b/xdk-build/src/python.rs
@@ -159,16 +159,12 @@ fn run_formatter(output_dir: &Path, venv_python_path: &Path, script_path: &Path)
     let stdout = String::from_utf8_lossy(&output.stdout);
     if !stdout.trim().is_empty() {
         println!();
-        stdout
-            .split("\n")
-            .collect::<Vec<&str>>()
-            .into_iter()
-            .for_each(|line| {
-                let parts = line.split(" ").collect::<Vec<&str>>();
-                if parts.len() == 2 {
-                    log_info!("{} {}", parts[0], parts[1].magenta());
-                }
-            });
+        stdout.split('\n').for_each(|line| {
+            let parts = line.split(' ').collect::<Vec<&str>>();
+            if parts.len() == 2 {
+                log_info!("{} {}", parts[0], parts[1].magenta());
+            }
+        });
         println!();
     }
 
diff --git a/xdk-lib/src/casing.rs b/xdk-lib/src/casing.rs
index 6463487e..0ee4c0d2 100644
--- a/xdk-lib/src/casing.rs
+++ b/xdk-lib/src/casing.rs
@@ -29,11 +29,7 @@ impl Casing {
                     result
                 }
             }
-            Casing::Pascal => words
-                .iter()
-                .map(|w| pascal_case(w))
-                .collect::<Vec<_>>()
-                .join(""),
+            Casing::Pascal => words.iter().map(|w| pascal_case(w)).collect::<String>(),
             Casing::Kebab => words.join("-").to_lowercase(),
             Casing::ScreamingSnake => words.join("_").to_uppercase(),
         }