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-rw-r--r--src/runtime/string_test.go456
1 files changed, 456 insertions, 0 deletions
diff --git a/src/runtime/string_test.go b/src/runtime/string_test.go
new file mode 100644
index 0000000..4eda12c
--- /dev/null
+++ b/src/runtime/string_test.go
@@ -0,0 +1,456 @@
+// 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 := rune(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 := rune(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)
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 17:55:14 +0000