syncthing/lib/rand/random_test.go
greatroar 198028d627
lib/rand: Optimizations (#7964)
rand.secureSource.Uint64 no longer allocates. rand.String uses a
strings.Builder. Benchmark results on linux/amd64:

name            old time/op    new time/op    delta
SecureSource-8    69.1ns ± 3%    51.7ns ± 3%   -25.21%  (p=0.000 n=20+10)
String-8          2.66µs ± 2%    1.95µs ± 1%   -26.61%  (p=0.000 n=10+10)

name            old alloc/op   new alloc/op   delta
SecureSource-8     8.00B ± 0%     0.00B       -100.00%  (p=0.000 n=20+10)
String-8            288B ± 0%       32B ± 0%   -88.89%  (p=0.000 n=10+10)

name            old allocs/op  new allocs/op  delta
SecureSource-8      1.00 ± 0%      0.00       -100.00%  (p=0.000 n=20+10)
String-8            33.0 ± 0%       1.0 ± 0%   -96.97%  (p=0.000 n=10+10)
2021-09-26 12:15:39 +02:00

54 lines
1.0 KiB
Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
package rand
import "testing"
func TestRandomString(t *testing.T) {
for _, l := range []int{0, 1, 2, 3, 4, 8, 42} {
s := String(l)
if len(s) != l {
t.Errorf("Incorrect length %d != %d", len(s), l)
}
}
strings := make([]string, 1000)
for i := range strings {
strings[i] = String(8)
for j := range strings {
if i == j {
continue
}
if strings[i] == strings[j] {
t.Errorf("Repeated random string %q", strings[i])
}
}
}
}
func TestRandomUint64(t *testing.T) {
ints := make([]uint64, 1000)
for i := range ints {
ints[i] = Uint64()
for j := range ints {
if i == j {
continue
}
if ints[i] == ints[j] {
t.Errorf("Repeated random int64 %d", ints[i])
}
}
}
}
func BenchmarkString(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
String(32)
}
}