summaryrefslogtreecommitdiff
path: root/libgo/go/testing/quick
diff options
context:
space:
mode:
Diffstat (limited to 'libgo/go/testing/quick')
-rw-r--r--libgo/go/testing/quick/quick.go364
-rw-r--r--libgo/go/testing/quick/quick_test.go147
2 files changed, 511 insertions, 0 deletions
diff --git a/libgo/go/testing/quick/quick.go b/libgo/go/testing/quick/quick.go
new file mode 100644
index 000000000..a5568b048
--- /dev/null
+++ b/libgo/go/testing/quick/quick.go
@@ -0,0 +1,364 @@
+// Copyright 2009 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.
+
+// This package implements utility functions to help with black box testing.
+package quick
+
+import (
+ "flag"
+ "fmt"
+ "math"
+ "os"
+ "rand"
+ "reflect"
+ "strings"
+)
+
+var defaultMaxCount *int = flag.Int("quickchecks", 100, "The default number of iterations for each check")
+
+// A Generator can generate random values of its own type.
+type Generator interface {
+ // Generate returns a random instance of the type on which it is a
+ // method using the size as a size hint.
+ Generate(rand *rand.Rand, size int) reflect.Value
+}
+
+// randFloat32 generates a random float taking the full range of a float32.
+func randFloat32(rand *rand.Rand) float32 {
+ f := rand.Float64() * math.MaxFloat32
+ if rand.Int()&1 == 1 {
+ f = -f
+ }
+ return float32(f)
+}
+
+// randFloat64 generates a random float taking the full range of a float64.
+func randFloat64(rand *rand.Rand) float64 {
+ f := rand.Float64()
+ if rand.Int()&1 == 1 {
+ f = -f
+ }
+ return f
+}
+
+// randInt64 returns a random integer taking half the range of an int64.
+func randInt64(rand *rand.Rand) int64 { return rand.Int63() - 1<<62 }
+
+// complexSize is the maximum length of arbitrary values that contain other
+// values.
+const complexSize = 50
+
+// Value returns an arbitrary value of the given type.
+// If the type implements the Generator interface, that will be used.
+// Note: in order to create arbitrary values for structs, all the members must be public.
+func Value(t reflect.Type, rand *rand.Rand) (value reflect.Value, ok bool) {
+ if m, ok := reflect.MakeZero(t).Interface().(Generator); ok {
+ return m.Generate(rand, complexSize), true
+ }
+
+ switch concrete := t.(type) {
+ case *reflect.BoolType:
+ return reflect.NewValue(rand.Int()&1 == 0), true
+ case *reflect.FloatType, *reflect.IntType, *reflect.UintType, *reflect.ComplexType:
+ switch t.Kind() {
+ case reflect.Float32:
+ return reflect.NewValue(randFloat32(rand)), true
+ case reflect.Float64:
+ return reflect.NewValue(randFloat64(rand)), true
+ case reflect.Complex64:
+ return reflect.NewValue(complex(randFloat32(rand), randFloat32(rand))), true
+ case reflect.Complex128:
+ return reflect.NewValue(complex(randFloat64(rand), randFloat64(rand))), true
+ case reflect.Int16:
+ return reflect.NewValue(int16(randInt64(rand))), true
+ case reflect.Int32:
+ return reflect.NewValue(int32(randInt64(rand))), true
+ case reflect.Int64:
+ return reflect.NewValue(randInt64(rand)), true
+ case reflect.Int8:
+ return reflect.NewValue(int8(randInt64(rand))), true
+ case reflect.Int:
+ return reflect.NewValue(int(randInt64(rand))), true
+ case reflect.Uint16:
+ return reflect.NewValue(uint16(randInt64(rand))), true
+ case reflect.Uint32:
+ return reflect.NewValue(uint32(randInt64(rand))), true
+ case reflect.Uint64:
+ return reflect.NewValue(uint64(randInt64(rand))), true
+ case reflect.Uint8:
+ return reflect.NewValue(uint8(randInt64(rand))), true
+ case reflect.Uint:
+ return reflect.NewValue(uint(randInt64(rand))), true
+ case reflect.Uintptr:
+ return reflect.NewValue(uintptr(randInt64(rand))), true
+ }
+ case *reflect.MapType:
+ numElems := rand.Intn(complexSize)
+ m := reflect.MakeMap(concrete)
+ for i := 0; i < numElems; i++ {
+ key, ok1 := Value(concrete.Key(), rand)
+ value, ok2 := Value(concrete.Elem(), rand)
+ if !ok1 || !ok2 {
+ return nil, false
+ }
+ m.SetElem(key, value)
+ }
+ return m, true
+ case *reflect.PtrType:
+ v, ok := Value(concrete.Elem(), rand)
+ if !ok {
+ return nil, false
+ }
+ p := reflect.MakeZero(concrete)
+ p.(*reflect.PtrValue).PointTo(v)
+ return p, true
+ case *reflect.SliceType:
+ numElems := rand.Intn(complexSize)
+ s := reflect.MakeSlice(concrete, numElems, numElems)
+ for i := 0; i < numElems; i++ {
+ v, ok := Value(concrete.Elem(), rand)
+ if !ok {
+ return nil, false
+ }
+ s.Elem(i).SetValue(v)
+ }
+ return s, true
+ case *reflect.StringType:
+ numChars := rand.Intn(complexSize)
+ codePoints := make([]int, numChars)
+ for i := 0; i < numChars; i++ {
+ codePoints[i] = rand.Intn(0x10ffff)
+ }
+ return reflect.NewValue(string(codePoints)), true
+ case *reflect.StructType:
+ s := reflect.MakeZero(t).(*reflect.StructValue)
+ for i := 0; i < s.NumField(); i++ {
+ v, ok := Value(concrete.Field(i).Type, rand)
+ if !ok {
+ return nil, false
+ }
+ s.Field(i).SetValue(v)
+ }
+ return s, true
+ default:
+ return nil, false
+ }
+
+ return
+}
+
+// A Config structure contains options for running a test.
+type Config struct {
+ // MaxCount sets the maximum number of iterations. If zero,
+ // MaxCountScale is used.
+ MaxCount int
+ // MaxCountScale is a non-negative scale factor applied to the default
+ // maximum. If zero, the default is unchanged.
+ MaxCountScale float64
+ // If non-nil, rand is a source of random numbers. Otherwise a default
+ // pseudo-random source will be used.
+ Rand *rand.Rand
+ // If non-nil, Values is a function which generates a slice of arbitrary
+ // Values that are congruent with the arguments to the function being
+ // tested. Otherwise, Values is used to generate the values.
+ Values func([]reflect.Value, *rand.Rand)
+}
+
+var defaultConfig Config
+
+// getRand returns the *rand.Rand to use for a given Config.
+func (c *Config) getRand() *rand.Rand {
+ if c.Rand == nil {
+ return rand.New(rand.NewSource(0))
+ }
+ return c.Rand
+}
+
+// getMaxCount returns the maximum number of iterations to run for a given
+// Config.
+func (c *Config) getMaxCount() (maxCount int) {
+ maxCount = c.MaxCount
+ if maxCount == 0 {
+ if c.MaxCountScale != 0 {
+ maxCount = int(c.MaxCountScale * float64(*defaultMaxCount))
+ } else {
+ maxCount = *defaultMaxCount
+ }
+ }
+
+ return
+}
+
+// A SetupError is the result of an error in the way that check is being
+// used, independent of the functions being tested.
+type SetupError string
+
+func (s SetupError) String() string { return string(s) }
+
+// A CheckError is the result of Check finding an error.
+type CheckError struct {
+ Count int
+ In []interface{}
+}
+
+func (s *CheckError) String() string {
+ return fmt.Sprintf("#%d: failed on input %s", s.Count, toString(s.In))
+}
+
+// A CheckEqualError is the result CheckEqual finding an error.
+type CheckEqualError struct {
+ CheckError
+ Out1 []interface{}
+ Out2 []interface{}
+}
+
+func (s *CheckEqualError) String() string {
+ return fmt.Sprintf("#%d: failed on input %s. Output 1: %s. Output 2: %s", s.Count, toString(s.In), toString(s.Out1), toString(s.Out2))
+}
+
+// Check looks for an input to f, any function that returns bool,
+// such that f returns false. It calls f repeatedly, with arbitrary
+// values for each argument. If f returns false on a given input,
+// Check returns that input as a *CheckError.
+// For example:
+//
+// func TestOddMultipleOfThree(t *testing.T) {
+// f := func(x int) bool {
+// y := OddMultipleOfThree(x)
+// return y%2 == 1 && y%3 == 0
+// }
+// if err := quick.Check(f, nil); err != nil {
+// t.Error(err)
+// }
+// }
+func Check(function interface{}, config *Config) (err os.Error) {
+ if config == nil {
+ config = &defaultConfig
+ }
+
+ f, fType, ok := functionAndType(function)
+ if !ok {
+ err = SetupError("argument is not a function")
+ return
+ }
+
+ if fType.NumOut() != 1 {
+ err = SetupError("function returns more than one value.")
+ return
+ }
+ if _, ok := fType.Out(0).(*reflect.BoolType); !ok {
+ err = SetupError("function does not return a bool")
+ return
+ }
+
+ arguments := make([]reflect.Value, fType.NumIn())
+ rand := config.getRand()
+ maxCount := config.getMaxCount()
+
+ for i := 0; i < maxCount; i++ {
+ err = arbitraryValues(arguments, fType, config, rand)
+ if err != nil {
+ return
+ }
+
+ if !f.Call(arguments)[0].(*reflect.BoolValue).Get() {
+ err = &CheckError{i + 1, toInterfaces(arguments)}
+ return
+ }
+ }
+
+ return
+}
+
+// CheckEqual looks for an input on which f and g return different results.
+// It calls f and g repeatedly with arbitrary values for each argument.
+// If f and g return different answers, CheckEqual returns a *CheckEqualError
+// describing the input and the outputs.
+func CheckEqual(f, g interface{}, config *Config) (err os.Error) {
+ if config == nil {
+ config = &defaultConfig
+ }
+
+ x, xType, ok := functionAndType(f)
+ if !ok {
+ err = SetupError("f is not a function")
+ return
+ }
+ y, yType, ok := functionAndType(g)
+ if !ok {
+ err = SetupError("g is not a function")
+ return
+ }
+
+ if xType != yType {
+ err = SetupError("functions have different types")
+ return
+ }
+
+ arguments := make([]reflect.Value, xType.NumIn())
+ rand := config.getRand()
+ maxCount := config.getMaxCount()
+
+ for i := 0; i < maxCount; i++ {
+ err = arbitraryValues(arguments, xType, config, rand)
+ if err != nil {
+ return
+ }
+
+ xOut := toInterfaces(x.Call(arguments))
+ yOut := toInterfaces(y.Call(arguments))
+
+ if !reflect.DeepEqual(xOut, yOut) {
+ err = &CheckEqualError{CheckError{i + 1, toInterfaces(arguments)}, xOut, yOut}
+ return
+ }
+ }
+
+ return
+}
+
+// arbitraryValues writes Values to args such that args contains Values
+// suitable for calling f.
+func arbitraryValues(args []reflect.Value, f *reflect.FuncType, config *Config, rand *rand.Rand) (err os.Error) {
+ if config.Values != nil {
+ config.Values(args, rand)
+ return
+ }
+
+ for j := 0; j < len(args); j++ {
+ var ok bool
+ args[j], ok = Value(f.In(j), rand)
+ if !ok {
+ err = SetupError(fmt.Sprintf("cannot create arbitrary value of type %s for argument %d", f.In(j), j))
+ return
+ }
+ }
+
+ return
+}
+
+func functionAndType(f interface{}) (v *reflect.FuncValue, t *reflect.FuncType, ok bool) {
+ v, ok = reflect.NewValue(f).(*reflect.FuncValue)
+ if !ok {
+ return
+ }
+ t = v.Type().(*reflect.FuncType)
+ return
+}
+
+func toInterfaces(values []reflect.Value) []interface{} {
+ ret := make([]interface{}, len(values))
+ for i, v := range values {
+ ret[i] = v.Interface()
+ }
+ return ret
+}
+
+func toString(interfaces []interface{}) string {
+ s := make([]string, len(interfaces))
+ for i, v := range interfaces {
+ s[i] = fmt.Sprintf("%#v", v)
+ }
+ return strings.Join(s, ", ")
+}
diff --git a/libgo/go/testing/quick/quick_test.go b/libgo/go/testing/quick/quick_test.go
new file mode 100644
index 000000000..b126e4a16
--- /dev/null
+++ b/libgo/go/testing/quick/quick_test.go
@@ -0,0 +1,147 @@
+// Copyright 2009 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 quick
+
+import (
+ "rand"
+ "reflect"
+ "testing"
+ "os"
+)
+
+func fBool(a bool) bool { return a }
+
+func fFloat32(a float32) float32 { return a }
+
+func fFloat64(a float64) float64 { return a }
+
+func fComplex64(a complex64) complex64 { return a }
+
+func fComplex128(a complex128) complex128 { return a }
+
+func fInt16(a int16) int16 { return a }
+
+func fInt32(a int32) int32 { return a }
+
+func fInt64(a int64) int64 { return a }
+
+func fInt8(a int8) int8 { return a }
+
+func fInt(a int) int { return a }
+
+func fUInt8(a uint8) uint8 { return a }
+
+func fMap(a map[int]int) map[int]int { return a }
+
+func fSlice(a []byte) []byte { return a }
+
+func fString(a string) string { return a }
+
+type TestStruct struct {
+ A int
+ B string
+}
+
+func fStruct(a TestStruct) TestStruct { return a }
+
+func fUint16(a uint16) uint16 { return a }
+
+func fUint32(a uint32) uint32 { return a }
+
+func fUint64(a uint64) uint64 { return a }
+
+func fUint8(a uint8) uint8 { return a }
+
+func fUint(a uint) uint { return a }
+
+func fUintptr(a uintptr) uintptr { return a }
+
+func fIntptr(a *int) *int {
+ b := *a
+ return &b
+}
+
+func reportError(property string, err os.Error, t *testing.T) {
+ if err != nil {
+ t.Errorf("%s: %s", property, err)
+ }
+}
+
+func TestCheckEqual(t *testing.T) {
+ reportError("fBool", CheckEqual(fBool, fBool, nil), t)
+ reportError("fFloat32", CheckEqual(fFloat32, fFloat32, nil), t)
+ reportError("fFloat64", CheckEqual(fFloat64, fFloat64, nil), t)
+ reportError("fComplex64", CheckEqual(fComplex64, fComplex64, nil), t)
+ reportError("fComplex128", CheckEqual(fComplex128, fComplex128, nil), t)
+ reportError("fInt16", CheckEqual(fInt16, fInt16, nil), t)
+ reportError("fInt32", CheckEqual(fInt32, fInt32, nil), t)
+ reportError("fInt64", CheckEqual(fInt64, fInt64, nil), t)
+ reportError("fInt8", CheckEqual(fInt8, fInt8, nil), t)
+ reportError("fInt", CheckEqual(fInt, fInt, nil), t)
+ reportError("fUInt8", CheckEqual(fUInt8, fUInt8, nil), t)
+ reportError("fInt32", CheckEqual(fInt32, fInt32, nil), t)
+ reportError("fMap", CheckEqual(fMap, fMap, nil), t)
+ reportError("fSlice", CheckEqual(fSlice, fSlice, nil), t)
+ reportError("fString", CheckEqual(fString, fString, nil), t)
+ reportError("fStruct", CheckEqual(fStruct, fStruct, nil), t)
+ reportError("fUint16", CheckEqual(fUint16, fUint16, nil), t)
+ reportError("fUint32", CheckEqual(fUint32, fUint32, nil), t)
+ reportError("fUint64", CheckEqual(fUint64, fUint64, nil), t)
+ reportError("fUint8", CheckEqual(fUint8, fUint8, nil), t)
+ reportError("fUint", CheckEqual(fUint, fUint, nil), t)
+ reportError("fUintptr", CheckEqual(fUintptr, fUintptr, nil), t)
+ reportError("fIntptr", CheckEqual(fIntptr, fIntptr, nil), t)
+}
+
+// This tests that ArbitraryValue is working by checking that all the arbitrary
+// values of type MyStruct have x = 42.
+type myStruct struct {
+ x int
+}
+
+func (m myStruct) Generate(r *rand.Rand, _ int) reflect.Value {
+ return reflect.NewValue(myStruct{x: 42})
+}
+
+func myStructProperty(in myStruct) bool { return in.x == 42 }
+
+func TestCheckProperty(t *testing.T) {
+ reportError("myStructProperty", Check(myStructProperty, nil), t)
+}
+
+func TestFailure(t *testing.T) {
+ f := func(x int) bool { return false }
+ err := Check(f, nil)
+ if err == nil {
+ t.Errorf("Check didn't return an error")
+ }
+ if _, ok := err.(*CheckError); !ok {
+ t.Errorf("Error was not a CheckError: %s", err)
+ }
+
+ err = CheckEqual(fUint, fUint32, nil)
+ if err == nil {
+ t.Errorf("#1 CheckEqual didn't return an error")
+ }
+ if _, ok := err.(SetupError); !ok {
+ t.Errorf("#1 Error was not a SetupError: %s", err)
+ }
+
+ err = CheckEqual(func(x, y int) {}, func(x int) {}, nil)
+ if err == nil {
+ t.Errorf("#2 CheckEqual didn't return an error")
+ }
+ if _, ok := err.(SetupError); !ok {
+ t.Errorf("#2 Error was not a SetupError: %s", err)
+ }
+
+ err = CheckEqual(func(x int) int { return 0 }, func(x int) int32 { return 0 }, nil)
+ if err == nil {
+ t.Errorf("#3 CheckEqual didn't return an error")
+ }
+ if _, ok := err.(SetupError); !ok {
+ t.Errorf("#3 Error was not a SetupError: %s", err)
+ }
+}