forked from alexkohler/prealloc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
prealloc_test.go
127 lines (108 loc) · 2.79 KB
/
prealloc_test.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
package main
import (
"go/token"
"testing"
"github.com/alexkohler/prealloc/pkg"
)
func Test_checkForPreallocations(t *testing.T) {
const filename = "testdata/sample.go"
fset := token.NewFileSet()
got, err := checkForPreallocations([]string{filename}, fset, true, true, true)
if err != nil {
t.Fatal(err)
}
want := []pkg.Hint{
pkg.Hint{
Pos: 63,
DeclaredSliceName: "y",
},
pkg.Hint{
Pos: 77,
DeclaredSliceName: "z",
},
pkg.Hint{
Pos: 102,
DeclaredSliceName: "t",
},
}
if len(got) != len(want) {
t.Fatalf("expected %d hints, but got %d: %+v", len(want), len(got), got)
}
for i := range got {
act, exp := got[i], want[i]
file := fset.File(act.Pos)
if file.Name() != filename {
t.Errorf("wrong hints[%d].Filename: %q (expected: %q)", i, file.Name(), filename)
}
actLineNumber := file.Position(act.Pos).Line
expLineNumber := file.Position(exp.Pos).Line
if actLineNumber != expLineNumber {
t.Errorf("wrong hints[%d].LineNumber: %d (expected: %d)", i, actLineNumber, expLineNumber)
}
if act.DeclaredSliceName != exp.DeclaredSliceName {
t.Errorf("wrong hints[%d].DeclaredSliceName: %q (expected: %q)", i, act.DeclaredSliceName, exp.DeclaredSliceName)
}
}
}
func BenchmarkSize10NoPreallocate(b *testing.B) {
existing := make([]int64, 10, 10)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Don't preallocate our initial slice
var init []int64
for _, element := range existing {
init = append(init, element)
}
}
}
func BenchmarkSize10Preallocate(b *testing.B) {
existing := make([]int64, 10, 10)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Preallocate our initial slice
init := make([]int64, 0, len(existing))
for _, element := range existing {
init = append(init, element)
}
}
}
func BenchmarkSize10PreallocateCopy(b *testing.B) {
existing := make([]int64, 10, 10)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Preallocate our initial slice
init := make([]int64, len(existing))
copy(init, existing)
}
}
func BenchmarkSize200NoPreallocate(b *testing.B) {
existing := make([]int64, 200, 200)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Don't preallocate our initial slice
var init []int64
for _, element := range existing {
init = append(init, element)
}
}
}
func BenchmarkSize200Preallocate(b *testing.B) {
existing := make([]int64, 200, 200)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Preallocate our initial slice
init := make([]int64, 0, len(existing))
for _, element := range existing {
init = append(init, element)
}
}
}
func BenchmarkSize200PreallocateCopy(b *testing.B) {
existing := make([]int64, 200, 200)
b.ResetTimer()
for i := 0; i < b.N; i++ {
// Preallocate our initial slice
init := make([]int64, len(existing))
copy(init, existing)
}
}