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// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package runtime_test
import (
"runtime"
"strings"
"testing"
)
func BenchmarkCompareStringEqual(b *testing.B) {
bytes := []byte("Hello Gophers!")
s1, s2 := string(bytes), string(bytes)
for i := 0; i < b.N; i++ {
if s1 != s2 {
b.Fatal("s1 != s2")
}
}
}
func BenchmarkCompareStringIdentical(b *testing.B) {
s1 := "Hello Gophers!"
s2 := s1
for i := 0; i < b.N; i++ {
if s1 != s2 {
b.Fatal("s1 != s2")
}
}
}
func BenchmarkCompareStringSameLength(b *testing.B) {
s1 := "Hello Gophers!"
s2 := "Hello, Gophers"
for i := 0; i < b.N; i++ {
if s1 == s2 {
b.Fatal("s1 == s2")
}
}
}
func BenchmarkCompareStringDifferentLength(b *testing.B) {
s1 := "Hello Gophers!"
s2 := "Hello, Gophers!"
for i := 0; i < b.N; i++ {
if s1 == s2 {
b.Fatal("s1 == s2")
}
}
}
func BenchmarkCompareStringBigUnaligned(b *testing.B) {
bytes := make([]byte, 0, 1<<20)
for len(bytes) < 1<<20 {
bytes = append(bytes, "Hello Gophers!"...)
}
s1, s2 := string(bytes), "hello"+string(bytes)
for i := 0; i < b.N; i++ {
if s1 != s2[len("hello"):] {
b.Fatal("s1 != s2")
}
}
b.SetBytes(int64(len(s1)))
}
func BenchmarkCompareStringBig(b *testing.B) {
bytes := make([]byte, 0, 1<<20)
for len(bytes) < 1<<20 {
bytes = append(bytes, "Hello Gophers!"...)
}
s1, s2 := string(bytes), string(bytes)
for i := 0; i < b.N; i++ {
if s1 != s2 {
b.Fatal("s1 != s2")
}
}
b.SetBytes(int64(len(s1)))
}
func BenchmarkRuneIterate(b *testing.B) {
bytes := make([]byte, 100)
for i := range bytes {
bytes[i] = byte('A')
}
s := string(bytes)
for i := 0; i < b.N; i++ {
for range s {
}
}
}
func BenchmarkRuneIterate2(b *testing.B) {
bytes := make([]byte, 100)
for i := range bytes {
bytes[i] = byte('A')
}
s := string(bytes)
for i := 0; i < b.N; i++ {
for range s {
}
}
}
func TestStringW(t *testing.T) {
strings := []string{
"hello",
"a\u5566\u7788b",
}
for _, s := range strings {
var b []uint16
for _, c := range s {
b = append(b, uint16(c))
if c != rune(uint16(c)) {
t.Errorf("bad test: stringW can't handle >16 bit runes")
}
}
b = append(b, 0)
r := runtime.GostringW(b)
if r != s {
t.Errorf("gostringW(%v) = %s, want %s", b, r, s)
}
}
}
func TestLargeStringConcat(t *testing.T) {
output := executeTest(t, largeStringConcatSource, nil)
want := "panic: " + strings.Repeat("0", 1<<10) + strings.Repeat("1", 1<<10) +
strings.Repeat("2", 1<<10) + strings.Repeat("3", 1<<10)
if !strings.HasPrefix(output, want) {
t.Fatalf("output does not start with %q:\n%s", want, output)
}
}
var largeStringConcatSource = `
package main
import "strings"
func main() {
s0 := strings.Repeat("0", 1<<10)
s1 := strings.Repeat("1", 1<<10)
s2 := strings.Repeat("2", 1<<10)
s3 := strings.Repeat("3", 1<<10)
s := s0 + s1 + s2 + s3
panic(s)
}
`
func TestGostringnocopy(t *testing.T) {
max := *runtime.Maxstring
b := make([]byte, max+10)
for i := uintptr(0); i < max+9; i++ {
b[i] = 'a'
}
_ = runtime.Gostringnocopy(&b[0])
newmax := *runtime.Maxstring
if newmax != max+9 {
t.Errorf("want %d, got %d", max+9, newmax)
}
}
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