Documentation
¶
Index ¶
- Variables
- func EncodeToString(val reflect.Value) string
- func FilterPredicate(in reflect.Type, predicate func(reflect.Value) bool) interface{}
- func HashToInt64(vals ...reflect.Value) int64
- func Mapper(in, out reflect.Type, mapFn func(reflect.Value) reflect.Value) interface{}
- func NewArray(t reflect.Type) func(Arbitrary) Arbitrary
- func NewErrorInvalidCollectionSize(collectionSize int, numberOfGenerators int) error
- func NewErrorInvalidTarget(target reflect.Type, generatorType string) error
- func NewMap(t reflect.Type) func(Arbitrary) Arbitrary
- func NewPtr(t reflect.Type) func(Arbitrary) Arbitrary
- func NewSlice(t reflect.Type) func(Arbitrary) Arbitrary
- func NewStruct(t reflect.Type) func(Arbitrary) Arbitrary
- type Arbitraries
- type Arbitrary
- type Generator
- type Random
- type RandomNumber
- type Shrinker
- func (shrinker Shrinker) Bind(binder binder, last Arbitrary) Shrinker
- func (shrinker Shrinker) Fail(err error) Shrinker
- func (shrinker Shrinker) Filter(predicate interface{}) Shrinker
- func (shrinker Shrinker) Map(mapper interface{}) Shrinker
- func (shrinker Shrinker) Or(next Shrinker) Shrinker
- func (shrinker Shrinker) Retry(maxRetries, remainingRetries uint, retryValue Arbitrary) Shrinker
- func (shrinker Shrinker) TransformAfter(transformer transform) Shrinker
- func (shrinker Shrinker) TransformBefore(transformer transform) Shrinker
- func (shrinker Shrinker) TransformOnceBefore(transformer transform) Shrinker
- func (shrinker Shrinker) Validate(validation func(Arbitrary) error) Shrinker
- type Validate
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( ErrorInvalidTarget = fmt.Errorf("Invalid generator target") ErrorInvalidConstraints = fmt.Errorf("Invalid generator constraints") ErrorInvalidCollectionSize = fmt.Errorf("Invalid number of generators for collection") ErrorInvalidConfig = fmt.Errorf("Invalid generator configuration") ErrorMapper = fmt.Errorf("Generator mapper is invalid") ErrorFilter = fmt.Errorf("Generator filter's predicate is invalid") ErrorBinder = fmt.Errorf("Geneartor binder is invalid") ErrorStream = fmt.Errorf("Failed to stream data") )
Functions ¶
func EncodeToString ¶
EncodeToString encodes val to it's string representation.
func FilterPredicate ¶
FilterPredicate returns predicate function that can be used in Filter methods for generators and shrinkers. First parameter in is used to define predicate function signature as input value. Output value is always bool. Second parameter predicateFn is a arbitrary function that defines the behaviour of predicate.
func HashToInt64 ¶
func Mapper ¶
Mapper returns mapper function that can be used with Map combinator for generators and shrinkers. Parameter "in' defines mapper's input type, parameter "out" defines mapper's output type while parameter "mapFn" implements mapping.
func NewErrorInvalidCollectionSize ¶ added in v0.3.0
func NewErrorInvalidTarget ¶ added in v0.3.0
Types ¶
type Arbitraries ¶
type Arbitraries []Arbitrary
func (Arbitraries) Values ¶
func (arbs Arbitraries) Values() []reflect.Value
type Arbitrary ¶
type Arbitrary struct {
Value reflect.Value // Final value
Elements Arbitraries // Arbitrary for each element in collection
Precursors Arbitraries // Precursor arbitraries from which this one is generated
Shrinker Shrinker
}
Arbitrary represents arbitrary type returned by shrinkers and generators.
func (Arbitrary) CompareType ¶ added in v0.2.0
type Generator ¶ added in v0.3.0
Generator returns Generate for a type specified by "target" parameter, that can be used to generate target's value using "bias" and "r".
func (Generator) Bind ¶ added in v0.3.0
Bind (combinator) returns bounded generator using "binder" parameter. Binder is a function that has one input and one output. Input's type must match generated value's type. Output type must be generator.Generator. Binder allows using generated value of one generator as an input to another generator. Error is returned if binder is invalid, generator returns an error or bound generator returns an error.
Example (StringWithRepeatingCharacter) ¶
This example demonstrates how to use Rune() generator and Bind() generator along with String() generator to build generator that generates string with single repeating character. Characters generated by Rune() generator will be used by Bind() combinator to setup rune constraints in String() generator returned by binder.
package main
import (
"fmt"
"github.com/steffnova/go-check/arbitrary"
"github.com/steffnova/go-check/constraints"
"github.com/steffnova/go-check/generator"
)
func main() {
streamer := generator.Streamer(
func(s string) {
fmt.Printf("%s\n", s)
},
generator.Rune(constraints.Rune{
MinCodePoint: 'a',
MaxCodePoint: 'z',
}).Bind(func(c rune) arbitrary.Generator {
return generator.String(constraints.String{
Rune: constraints.Rune{
MinCodePoint: c,
MaxCodePoint: c,
},
Length: constraints.Length{
Min: 5,
Max: 10,
},
})
}),
)
if err := generator.Stream(0, 10, streamer); err != nil {
panic(err)
}
}
Output: vvvvvvv dddddddddd jjjjjj ooooo bbbbbbbbbb xxxxxxxxxx aaaaaaaa oooooo wwwwwwwwww ggggg
func (Generator) Filter ¶ added in v0.3.0
Filter (combinator) returns a generator that generates value only if predicate is satisfied. Predicate is a function that has one input and one output. Predicate's input parameter must match generator's target type, and output parameter must be bool. Error is returned predicate is invalid, or generator for predicate's input returns an error.
NOTE: Returned generator will retry generation until predicate is satisfied, which can impact the generator's speed.
Example (EvenInt) ¶
This example demonstrates how to use Int() generator and Filter combinator to build a generator for generation of even integer numbers. Int values generated by Int() generator that are divisable by 2 will be filtered by Filter combinator.
package main
import (
"fmt"
"github.com/steffnova/go-check/constraints"
"github.com/steffnova/go-check/generator"
)
func main() {
streamer := generator.Streamer(
func(n int) {
fmt.Printf("%d\n", n)
},
generator.Int(constraints.Int{
Min: 0,
Max: 100,
},
).Filter(func(n int) bool {
return n%2 == 0
}),
)
if err := generator.Stream(0, 10, streamer); err != nil {
panic(err)
}
}
Output: 16 80 86 22 84 64 30 40 62 92
func (Generator) Map ¶ added in v0.3.0
Map (combinator) returns generator that maps generated value to a new one using mapper. Mapper must be a function that has one input and one output. Mapper's input type must match generated value's type and Mapper's output type must match generator's target type. Error is returned if mapper is invalid or if generator of mapper's input type returns an error.
Example (EvenInt) ¶
This example demonstrates how to use Int() generator and Map combinator to build a generator for generation of even integer numbers. Each generated int value by Int() generator will be multiplied by 2 by mapper.
package main
import (
"fmt"
"github.com/steffnova/go-check/constraints"
"github.com/steffnova/go-check/generator"
)
func main() {
streamer := generator.Streamer(
func(n int) {
fmt.Printf("%d\n", n)
},
generator.Int(constraints.Int{
Min: 0,
Max: 100,
}).Map(func(n int) int {
return n * 2
}),
)
if err := generator.Stream(0, 10, streamer); err != nil {
panic(err)
}
}
Output: 62 32 160 172 138 44 168 6 128 60
Example (OrderedIntSlice) ¶
This example demonstrates how to use Slice(Int()) generator and Map combinator to build a generator for generation slice of ordered intger numbers. Each generated []int value by Slice(Int()) generator will be sorted by mapper.
package main
import (
"fmt"
"sort"
"github.com/steffnova/go-check/constraints"
"github.com/steffnova/go-check/generator"
)
func main() {
streamer := generator.Streamer(
func(n []int) {
fmt.Printf("%d\n", n)
},
generator.Slice(
generator.Int(constraints.Int{
Min: 0,
Max: 10000,
}),
constraints.Length{
Min: 0,
Max: 10,
}).Map(func(ns []int) []int {
sort.SliceStable(ns, func(i, j int) bool {
return ns[i] < ns[j]
})
return ns
}),
)
if err := generator.Stream(0, 10, streamer); err != nil {
panic(err)
}
}
Output: [259 1069 1984 5150 5910] [3323] [2140 3257 3378 5063 5836 8213 8701 9832] [1247 3422 4175 4605 4904 5523 5629 5705 9029 9609] [1943 3465 4132 8913] [30 2361 3384 6926] [] [271 1007 2281 8190 8477 9452] [3746 5588 8797 9599] [19 697 3795 5496 6269 6795 7065 7552]
type Random ¶ added in v0.3.0
type Random interface {
// Uint64 generates random uint64 in specified range [min, max] (inclusive)
Uint64(constraints.Uint64) uint64
// Split returns new Random that can be used idenpendently of original. Random
// returned by Split can have it's seed changed without affecting the original
Split() Random
// Seed seeds Random with seed value
Seed(seed int64)
}
Random is an interface for random number generation
type RandomNumber ¶ added in v0.3.0
RandomNumber is implementation of Random interface
func (RandomNumber) Seed ¶ added in v0.3.0
func (r RandomNumber) Seed(seed int64)
Seed is implementation of Random.Seed
func (RandomNumber) Split ¶ added in v0.3.0
func (r RandomNumber) Split() Random
Split is implementation of Random.Split
func (RandomNumber) Uint64 ¶ added in v0.3.0
func (r RandomNumber) Uint64(limit constraints.Uint64) uint64
Uint64 is implementation of Random.Uint64
type Shrinker ¶ added in v0.3.0
func (Shrinker) Bind ¶ added in v0.3.0
Bind returns a shrinker that uses the shrunk value to generate shrink returned by binder. Binder is not guaranteed to be deterministic, as it returns new result value based on root shrinker's shrink and it should be considered non-deterministic. Two shrinkers needs to be passed alongside binder, next and lastFailing. Next shrinker is the shrinker from the previous iteration of shrinking is shrinkering where lastFail that caused last property falsification. Because of "non-deterministic" property of binder, Bind is best paired with Retry combinator that can improve shrinking efficiency.
func (Shrinker) Retry ¶ added in v0.3.0
Retry returns a shrinker that returns retryValue, and shrinker receiver until either reminingRetries equals 0 or propertyFailed is true. Retry is useful for shrinkers that do not shrink deterministically like shrinkers returned by Bind. On deterministic shrinkers this has no effect and will only increase total time of shrinking process.
func (Shrinker) TransformAfter ¶ added in v0.3.0
func (Shrinker) TransformBefore ¶ added in v0.3.0
func (Shrinker) TransformOnceBefore ¶ added in v0.3.0
type Validate ¶ added in v0.2.0
func ValidateArray ¶ added in v0.2.0
func ValidateArray() Validate
func ValidateMap ¶ added in v0.2.0
func ValidateMap() Validate
func ValidateSlice ¶ added in v0.2.0
func ValidateSlice() Validate
func ValidateStruct ¶ added in v0.2.0
func ValidateStruct() Validate
Source Files