rust/library/alloc/benches/string.rs

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use std::iter::repeat;
use test::{black_box, Bencher};
#[bench]
fn bench_with_capacity(b: &mut Bencher) {
b.iter(|| String::with_capacity(100));
}
#[bench]
fn bench_push_str(b: &mut Bencher) {
let s = "ศไทย中华Việt Nam; Mary had a little lamb, Little lamb";
b.iter(|| {
let mut r = String::new();
r.push_str(s);
});
}
const REPETITIONS: u64 = 10_000;
#[bench]
fn bench_push_str_one_byte(b: &mut Bencher) {
b.bytes = REPETITIONS;
b.iter(|| {
let mut r = String::new();
for _ in 0..REPETITIONS {
r.push_str("a")
}
});
}
#[bench]
fn bench_push_char_one_byte(b: &mut Bencher) {
b.bytes = REPETITIONS;
b.iter(|| {
let mut r = String::new();
for _ in 0..REPETITIONS {
r.push('a')
}
});
}
#[bench]
fn bench_push_char_two_bytes(b: &mut Bencher) {
b.bytes = REPETITIONS * 2;
b.iter(|| {
let mut r = String::new();
for _ in 0..REPETITIONS {
r.push('â')
}
});
}
#[bench]
fn from_utf8_lossy_100_ascii(b: &mut Bencher) {
let s = b"Hello there, the quick brown fox jumped over the lazy dog! \
Lorem ipsum dolor sit amet, consectetur. ";
assert_eq!(100, s.len());
b.iter(|| {
let _ = String::from_utf8_lossy(s);
});
}
#[bench]
fn from_utf8_lossy_100_multibyte(b: &mut Bencher) {
let s = "𐌀𐌖𐌋𐌄𐌑𐌉ปรدولة الكويتทศไทย中华𐍅𐌿𐌻𐍆𐌹𐌻𐌰".as_bytes();
assert_eq!(100, s.len());
b.iter(|| {
let _ = String::from_utf8_lossy(s);
});
}
#[bench]
fn from_utf8_lossy_invalid(b: &mut Bencher) {
let s = b"Hello\xC0\x80 There\xE6\x83 Goodbye";
b.iter(|| {
let _ = String::from_utf8_lossy(s);
});
}
#[bench]
fn from_utf8_lossy_100_invalid(b: &mut Bencher) {
let s = repeat(0xf5).take(100).collect::<Vec<_>>();
b.iter(|| {
let _ = String::from_utf8_lossy(&s);
});
}
#[bench]
fn bench_exact_size_shrink_to_fit(b: &mut Bencher) {
let s = "Hello there, the quick brown fox jumped over the lazy dog! \
Lorem ipsum dolor sit amet, consectetur. ";
// ensure our operation produces an exact-size string before we benchmark it
let mut r = String::with_capacity(s.len());
r.push_str(s);
assert_eq!(r.len(), r.capacity());
b.iter(|| {
let mut r = String::with_capacity(s.len());
r.push_str(s);
r.shrink_to_fit();
r
});
}
#[bench]
fn bench_from_str(b: &mut Bencher) {
let s = "Hello there, the quick brown fox jumped over the lazy dog! \
Lorem ipsum dolor sit amet, consectetur. ";
b.iter(|| String::from(s))
}
#[bench]
fn bench_from(b: &mut Bencher) {
let s = "Hello there, the quick brown fox jumped over the lazy dog! \
Lorem ipsum dolor sit amet, consectetur. ";
b.iter(|| String::from(s))
}
#[bench]
fn bench_to_string(b: &mut Bencher) {
let s = "Hello there, the quick brown fox jumped over the lazy dog! \
Lorem ipsum dolor sit amet, consectetur. ";
b.iter(|| s.to_string())
}
#[bench]
fn bench_insert_char_short(b: &mut Bencher) {
let s = "Hello, World!";
b.iter(|| {
let mut x = String::from(s);
black_box(&mut x).insert(6, black_box(' '));
x
})
}
#[bench]
fn bench_insert_char_long(b: &mut Bencher) {
let s = "Hello, World!";
b.iter(|| {
let mut x = String::from(s);
black_box(&mut x).insert(6, black_box('❤'));
x
})
}
#[bench]
fn bench_insert_str_short(b: &mut Bencher) {
let s = "Hello, World!";
b.iter(|| {
let mut x = String::from(s);
black_box(&mut x).insert_str(6, black_box(" "));
x
})
}
#[bench]
fn bench_insert_str_long(b: &mut Bencher) {
let s = "Hello, World!";
b.iter(|| {
let mut x = String::from(s);
black_box(&mut x).insert_str(6, black_box(" rustic "));
x
})
}