benchmarks: reduce allocations in run_util_function (uutils#10378)

Author: xtqqczze

src/uucore/Cargo.toml

@@ -96,6 +96,7 @@ nix = { workspace = true, features = [
   "poll",
 ] }
 xattr = { workspace = true, optional = true }
+itertools = { workspace = true, optional = true }
 
 [dev-dependencies]
 tempfile = { workspace = true }
@@ -186,4 +187,4 @@ wide = []
 tty = []
 time = ["jiff"]
 uptime = ["jiff", "libc", "windows-sys", "utmpx", "utmp-classic"]
-benchmark = ["divan", "tempfile"]
+benchmark = ["divan", "itertools", "tempfile"]

src/uucore/src/lib/features/benchmark.rs

@@ -12,6 +12,8 @@ use std::fs::File;
 use std::io::{BufWriter, Write};
 use std::path::{Path, PathBuf};
 
+use itertools::Itertools as _;
+
 /// Create a temporary file with test data
 pub fn create_test_file(data: &[u8], temp_dir: &Path) -> PathBuf {
     let file_path = temp_dir.join("test_data.txt");
@@ -32,8 +34,9 @@ where
     F: FnOnce(std::vec::IntoIter<std::ffi::OsString>) -> i32,
 {
     // Prepend a dummy program name as argv[0] since clap expects it
-    let mut os_args: Vec<std::ffi::OsString> = vec!["benchmark".into()];
-    os_args.extend(args.iter().map(|s| (*s).into()));
+    let os_args = std::iter::once("benchmark".into())
+        .chain(args.iter().map(Into::into))
+        .collect_vec();
     util_func(os_args.into_iter())
 }