forked from leanovate/gopter
/
slice_of.go
89 lines (76 loc) · 2.57 KB
/
slice_of.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
package gen
import (
"reflect"
"github.com/leanovate/gopter"
)
// SliceOf generates an arbitrary slice of generated elements
// genParams.MaxSize sets an (exclusive) upper limit on the size of the slice
// genParams.MinSize sets an (inclusive) lower limit on the size of the slice
func SliceOf(elementGen gopter.Gen) gopter.Gen {
return func(genParams *gopter.GenParameters) *gopter.GenResult {
len := 0
if genParams.MaxSize > 0 || genParams.MinSize > 0 {
if genParams.MinSize > genParams.MaxSize {
panic("GenParameters.MinSize must be <= GenParameters.MaxSize")
}
if genParams.MaxSize == genParams.MinSize {
len = genParams.MaxSize
} else {
len = genParams.Rng.Intn(genParams.MaxSize-genParams.MinSize) + genParams.MinSize
}
}
result, elementSieve, elementShrinker := genSlice(elementGen, genParams, len)
genResult := gopter.NewGenResult(result.Interface(), SliceShrinker(elementShrinker))
if elementSieve != nil {
genResult.Sieve = forAllSieve(elementSieve)
}
return genResult
}
}
// SliceOfN generates a slice of generated elements with definied length
func SliceOfN(len int, elementGen gopter.Gen) gopter.Gen {
return func(genParams *gopter.GenParameters) *gopter.GenResult {
result, elementSieve, elementShrinker := genSlice(elementGen, genParams, len)
genResult := gopter.NewGenResult(result.Interface(), SliceShrinkerOne(elementShrinker))
if elementSieve != nil {
genResult.Sieve = func(v interface{}) bool {
rv := reflect.ValueOf(v)
return rv.Len() == len && forAllSieve(elementSieve)(v)
}
} else {
genResult.Sieve = func(v interface{}) bool {
return reflect.ValueOf(v).Len() == len
}
}
return genResult
}
}
func genSlice(elementGen gopter.Gen, genParams *gopter.GenParameters, len int) (reflect.Value, func(interface{}) bool, gopter.Shrinker) {
element := elementGen(genParams)
elementSieve := element.Sieve
elementShrinker := element.Shrinker
result := reflect.MakeSlice(reflect.SliceOf(element.ResultType), 0, len)
for i := 0; i < len; i++ {
value, ok := element.Retrieve()
if ok {
if value == nil {
result = reflect.Append(result, reflect.Zero(element.ResultType))
} else {
result = reflect.Append(result, reflect.ValueOf(value))
}
}
element = elementGen(genParams)
}
return result, elementSieve, elementShrinker
}
func forAllSieve(elementSieve func(interface{}) bool) func(interface{}) bool {
return func(v interface{}) bool {
rv := reflect.ValueOf(v)
for i := rv.Len() - 1; i >= 0; i-- {
if !elementSieve(rv.Index(i).Interface()) {
return false
}
}
return true
}
}