diff options
Diffstat (limited to 'src/runtime/string_test.go')
-rw-r--r-- | src/runtime/string_test.go | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/src/runtime/string_test.go b/src/runtime/string_test.go new file mode 100644 index 000000000..1551ecc82 --- /dev/null +++ b/src/runtime/string_test.go @@ -0,0 +1,160 @@ +// 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) + } +} |