1package yaml
2
3import (
4 "reflect"
5 "unicode"
6)
7
8type keyList []reflect.Value
9
10func (l keyList) Len() int { return len(l) }
11func (l keyList) Swap(i, j int) { l[i], l[j] = l[j], l[i] }
12func (l keyList) Less(i, j int) bool {
13 a := l[i]
14 b := l[j]
15 ak := a.Kind()
16 bk := b.Kind()
17 for (ak == reflect.Interface || ak == reflect.Ptr) && !a.IsNil() {
18 a = a.Elem()
19 ak = a.Kind()
20 }
21 for (bk == reflect.Interface || bk == reflect.Ptr) && !b.IsNil() {
22 b = b.Elem()
23 bk = b.Kind()
24 }
25 af, aok := keyFloat(a)
26 bf, bok := keyFloat(b)
27 if aok && bok {
28 if af != bf {
29 return af < bf
30 }
31 if ak != bk {
32 return ak < bk
33 }
34 return numLess(a, b)
35 }
36 if ak != reflect.String || bk != reflect.String {
37 return ak < bk
38 }
39 ar, br := []rune(a.String()), []rune(b.String())
40 for i := 0; i < len(ar) && i < len(br); i++ {
41 if ar[i] == br[i] {
42 continue
43 }
44 al := unicode.IsLetter(ar[i])
45 bl := unicode.IsLetter(br[i])
46 if al && bl {
47 return ar[i] < br[i]
48 }
49 if al || bl {
50 return bl
51 }
52 var ai, bi int
53 var an, bn int64
54 if ar[i] == '0' || br[i] == '0' {
55 for j := i-1; j >= 0 && unicode.IsDigit(ar[j]); j-- {
56 if ar[j] != '0' {
57 an = 1
58 bn = 1
59 break
60 }
61 }
62 }
63 for ai = i; ai < len(ar) && unicode.IsDigit(ar[ai]); ai++ {
64 an = an*10 + int64(ar[ai]-'0')
65 }
66 for bi = i; bi < len(br) && unicode.IsDigit(br[bi]); bi++ {
67 bn = bn*10 + int64(br[bi]-'0')
68 }
69 if an != bn {
70 return an < bn
71 }
72 if ai != bi {
73 return ai < bi
74 }
75 return ar[i] < br[i]
76 }
77 return len(ar) < len(br)
78}
79
80// keyFloat returns a float value for v if it is a number/bool
81// and whether it is a number/bool or not.
82func keyFloat(v reflect.Value) (f float64, ok bool) {
83 switch v.Kind() {
84 case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
85 return float64(v.Int()), true
86 case reflect.Float32, reflect.Float64:
87 return v.Float(), true
88 case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
89 return float64(v.Uint()), true
90 case reflect.Bool:
91 if v.Bool() {
92 return 1, true
93 }
94 return 0, true
95 }
96 return 0, false
97}
98
99// numLess returns whether a < b.
100// a and b must necessarily have the same kind.
101func numLess(a, b reflect.Value) bool {
102 switch a.Kind() {
103 case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
104 return a.Int() < b.Int()
105 case reflect.Float32, reflect.Float64:
106 return a.Float() < b.Float()
107 case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
108 return a.Uint() < b.Uint()
109 case reflect.Bool:
110 return !a.Bool() && b.Bool()
111 }
112 panic("not a number")
113}