diff options
Diffstat (limited to 'libgo/go/testing/quick')
-rw-r--r-- | libgo/go/testing/quick/quick.go | 364 | ||||
-rw-r--r-- | libgo/go/testing/quick/quick_test.go | 147 |
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) + } +} |