// 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"
"strconv"
"strings"
"testing"
"unicode/utf8"
)
// Strings and slices that don't escape and fit into tmpBuf are stack allocated,
// which defeats using AllocsPerRun to test other optimizations.
const sizeNoStack = 100
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 BenchmarkConcatStringAndBytes(b *testing.B) {
s1 := []byte("Gophers!")
for i := 0; i < b.N; i++ {
_ = "Hello " + string(s1)
}
}
var escapeString string
func BenchmarkSliceByteToString(b *testing.B) {
buf := []byte{'!'}
for n := 0; n < 8; n++ {
b.Run(strconv.Itoa(len(buf)), func(b *testing.B) {
for i := 0; i < b.N; i++ {
escapeString = string(buf)
}
})
buf = append(buf, buf...)
}
}
var stringdata = []struct{ name, data string }{
{"ASCII", "01234567890"},
{"Japanese", "日本語日本語日本語"},
{"MixedLength", "$Ѐࠀက퀀𐀀\U00040000\U0010FFFF"},
}
var sinkInt int
func BenchmarkRuneCount(b *testing.B) {
// Each sub-benchmark counts the runes in a string in a different way.
b.Run("lenruneslice", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
sinkInt += len([]rune(sd.data))
}
})
}
})
b.Run("rangeloop", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
n := 0
for range sd.data {
n++
}
sinkInt += n
}
})
}
})
b.Run("utf8.RuneCountInString", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
sinkInt += utf8.RuneCountInString(sd.data)
}
})
}
})
}
func BenchmarkRuneIterate(b *testing.B) {
b.Run("range", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
for range sd.data {
}
}
})
}
})
b.Run("range1", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
for range sd.data {
}
}
})
}
})
b.Run("range2", func(b *testing.B) {
for _, sd := range stringdata {
b.Run(sd.name, func(b *testing.B) {
for i := 0; i < b.N; i++ {
for range sd.data {
}
}
})
}
})
}
func BenchmarkArrayEqual(b *testing.B) {
a1 := [16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
a2 := [16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
b.ResetTimer()
for i := 0; i < b.N; i++ {
if a1 != a2 {
b.Fatal("not equal")
}
}
}
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 := runTestProg(t, "testprog", "stringconcat")
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)
}
}
func TestCompareTempString(t *testing.T) {
s := strings.Repeat("x", sizeNoStack)
b := []byte(s)
n := testing.AllocsPerRun(1000, func() {
if string(b) != s {
t.Fatalf("strings are not equal: '%v' and '%v'", string(b), s)
}
if string(b) == s {
} else {
t.Fatalf("strings are not equal: '%v' and '%v'", string(b), s)
}
})
if n != 0 {
t.Fatalf("want 0 allocs, got %v", n)
}
}
func TestStringIndexHaystack(t *testing.T) {
// See issue 25864.
haystack := []byte("hello")
needle := "ll"
n := testing.AllocsPerRun(1000, func() {
if strings.Index(string(haystack), needle) != 2 {
t.Fatalf("needle not found")
}
})
if n != 0 {
t.Fatalf("want 0 allocs, got %v", n)
}
}
func TestStringIndexNeedle(t *testing.T) {
// See issue 25864.
haystack := "hello"
needle := []byte("ll")
n := testing.AllocsPerRun(1000, func() {
if strings.Index(haystack, string(needle)) != 2 {
t.Fatalf("needle not found")
}
})
if n != 0 {
t.Fatalf("want 0 allocs, got %v", n)
}
}
func TestStringOnStack(t *testing.T) {
s := ""
for i := 0; i < 3; i++ {
s = "a" + s + "b" + s + "c"
}
if want := "aaabcbabccbaabcbabccc"; s != want {
t.Fatalf("want: '%v', got '%v'", want, s)
}
}
func TestIntString(t *testing.T) {
// Non-escaping result of intstring.
s := ""
for i := 0; i < 4; i++ {
s += string(i+'0') + string(i+'0'+1)
}
if want := "01122334"; s != want {
t.Fatalf("want '%v', got '%v'", want, s)
}
// Escaping result of intstring.
var a [4]string
for i := 0; i < 4; i++ {
a[i] = string(i + '0')
}
s = a[0] + a[1] + a[2] + a[3]
if want := "0123"; s != want {
t.Fatalf("want '%v', got '%v'", want, s)
}
}
func TestIntStringAllocs(t *testing.T) {
unknown := '0'
n := testing.AllocsPerRun(1000, func() {
s1 := string(unknown)
s2 := string(unknown + 1)
if s1 == s2 {
t.Fatalf("bad")
}
})
if n != 0 {
t.Fatalf("want 0 allocs, got %v", n)
}
}
func TestRangeStringCast(t *testing.T) {
s := strings.Repeat("x", sizeNoStack)
n := testing.AllocsPerRun(1000, func() {
for i, c := range []byte(s) {
if c != s[i] {
t.Fatalf("want '%c' at pos %v, got '%c'", s[i], i, c)
}
}
})
if n != 0 {
t.Fatalf("want 0 allocs, got %v", n)
}
}
func isZeroed(b []byte) bool {
for _, x := range b {
if x != 0 {
return false
}
}
return true
}
func isZeroedR(r []rune) bool {
for _, x := range r {
if x != 0 {
return false
}
}
return true
}
func TestString2Slice(t *testing.T) {
// Make sure we don't return slices that expose
// an unzeroed section of stack-allocated temp buf
// between len and cap. See issue 14232.
s := "foož"
b := ([]byte)(s)
if !isZeroed(b[len(b):cap(b)]) {
t.Errorf("extra bytes not zeroed")
}
r := ([]rune)(s)
if !isZeroedR(r[len(r):cap(r)]) {
t.Errorf("extra runes not zeroed")
}
}
const intSize = 32 << (^uint(0) >> 63)
type atoi64Test struct {
in string
out int64
ok bool
}
var atoi64tests = []atoi64Test{
{"", 0, false},
{"0", 0, true},
{"-0", 0, true},
{"1", 1, true},
{"-1", -1, true},
{"12345", 12345, true},
{"-12345", -12345, true},
{"012345", 12345, true},
{"-012345", -12345, true},
{"12345x", 0, false},
{"-12345x", 0, false},
{"98765432100", 98765432100, true},
{"-98765432100", -98765432100, true},
{"20496382327982653440", 0, false},
{"-20496382327982653440", 0, false},
{"9223372036854775807", 1<<63 - 1, true},
{"-9223372036854775807", -(1<<63 - 1), true},
{"9223372036854775808", 0, false},
{"-9223372036854775808", -1 << 63, true},
{"9223372036854775809", 0, false},
{"-9223372036854775809", 0, false},
}
func TestAtoi(t *testing.T) {
switch intSize {
case 32:
for i := range atoi32tests {
test := &atoi32tests[i]
out, ok := runtime.Atoi(test.in)
if test.out != int32(out) || test.ok != ok {
t.Errorf("atoi(%q) = (%v, %v) want (%v, %v)",
test.in, out, ok, test.out, test.ok)
}
}
case 64:
for i := range atoi64tests {
test := &atoi64tests[i]
out, ok := runtime.Atoi(test.in)
if test.out != int64(out) || test.ok != ok {
t.Errorf("atoi(%q) = (%v, %v) want (%v, %v)",
test.in, out, ok, test.out, test.ok)
}
}
}
}
type atoi32Test struct {
in string
out int32
ok bool
}
var atoi32tests = []atoi32Test{
{"", 0, false},
{"0", 0, true},
{"-0", 0, true},
{"1", 1, true},
{"-1", -1, true},
{"12345", 12345, true},
{"-12345", -12345, true},
{"012345", 12345, true},
{"-012345", -12345, true},
{"12345x", 0, false},
{"-12345x", 0, false},
{"987654321", 987654321, true},
{"-987654321", -987654321, true},
{"2147483647", 1<<31 - 1, true},
{"-2147483647", -(1<<31 - 1), true},
{"2147483648", 0, false},
{"-2147483648", -1 << 31, true},
{"2147483649", 0, false},
{"-2147483649", 0, false},
}
func TestAtoi32(t *testing.T) {
for i := range atoi32tests {
test := &atoi32tests[i]
out, ok := runtime.Atoi32(test.in)
if test.out != out || test.ok != ok {
t.Errorf("atoi32(%q) = (%v, %v) want (%v, %v)",
test.in, out, ok, test.out, test.ok)
}
}
}