Rollup merge of #57032 - RalfJung:alloc-bench-deprecations, r=Centril

fix deprecation warnings in liballoc benches

Cargo.lock

@@ -18,6 +18,7 @@ dependencies = [
  "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]

src/liballoc/Cargo.toml

@@ -15,6 +15,7 @@ compiler_builtins = { version = "0.1.0", features = ['rustc-dep-of-std'] }
 
 [dev-dependencies]
 rand = "0.6"
+rand_xorshift = "0.1"
 
 [[test]]
 name = "collectionstests"

src/liballoc/benches/btree/map.rs

@@ -12,7 +12,7 @@
 use std::iter::Iterator;
 use std::vec::Vec;
 use std::collections::BTreeMap;
-use rand::{Rng, thread_rng};
+use rand::{Rng, seq::SliceRandom, thread_rng};
 use test::{Bencher, black_box};
 
 macro_rules! map_insert_rand_bench {
@@ -78,7 +78,7 @@ macro_rules! map_find_rand_bench {
                 map.insert(k, k);
             }
 
-            rng.shuffle(&mut keys);
+            keys.shuffle(&mut rng);
 
             // measure
             let mut i = 0;

src/liballoc/benches/lib.rs

@@ -13,6 +13,7 @@
 #![feature(test)]
 
 extern crate rand;
+extern crate rand_xorshift;
 extern crate test;
 
 mod btree;

src/liballoc/benches/slice.rs

@@ -12,8 +12,9 @@ use rand::{thread_rng};
 use std::mem;
 use std::ptr;
 
-use rand::{Rng, SeedableRng, XorShiftRng};
+use rand::{Rng, SeedableRng};
 use rand::distributions::{Standard, Alphanumeric};
+use rand_xorshift::XorShiftRng;
 use test::{Bencher, black_box};
 
 #[bench]

src/liballoc/benches/str.rs

@@ -274,11 +274,11 @@ make_test!(split_a_str, s, s.split("a").count());
 make_test!(trim_ascii_char, s, {
     s.trim_matches(|c: char| c.is_ascii())
 });
-make_test!(trim_left_ascii_char, s, {
-    s.trim_left_matches(|c: char| c.is_ascii())
+make_test!(trim_start_ascii_char, s, {
+    s.trim_start_matches(|c: char| c.is_ascii())
 });
-make_test!(trim_right_ascii_char, s, {
-    s.trim_right_matches(|c: char| c.is_ascii())
+make_test!(trim_end_ascii_char, s, {
+    s.trim_end_matches(|c: char| c.is_ascii())
 });
 
 make_test!(find_underscore_char, s, s.find('_'));