How to use TypeBehind method of td Package

Best Go-testdeep code snippet using td.TypeBehind

t_anchor.go

Source:t_anchor.go

...49// Anchor returns a typed value allowing to anchor the TestDeep50// operator operator in a go classic literal like a struct, slice,51// array or map value.52//53// If the TypeBehind method of operator returns non-nil, model can be54// omitted (like with [Between] operator in the example55// below). Otherwise, model should contain only one value56// corresponding to the returning type. It can be:57//   - a go value: returning type is the type of the value,58//     whatever the value is;59//   - a [reflect.Type].60//61// It returns a typed value ready to be embed in a go data structure to62// be compared using [T.Cmp] or [T.CmpLax]:63//64//	import (65//	  "testing"66//67//	  "github.com/maxatome/go-testdeep/td"68//	)69//70//	func TestFunc(tt *testing.T) {71//	  got := Func()72//73//	  t := td.NewT(tt)74//	  t.Cmp(got, &MyStruct{75//	    Name:    "Bob",76//	    Details: &MyDetails{77//	      Nick: t.Anchor(td.HasPrefix("Bobby"), "").(string),78//	      Age:  t.Anchor(td.Between(40, 50)).(int),79//	    },80//	  })81//	}82//83// In this example:84//85//   - [HasPrefix] operates on several input types (string,86//     [fmt.Stringer], error, â¦), so its TypeBehind method returns always87//     nil as it can not guess in advance on which type it operates. In88//     this case, we must pass "" as model parameter in order to tell it89//     to return the string type. Note that the .(string) type assertion90//     is then mandatory to conform to the strict type checking.91//   - [Between], on its side, knows the type on which it operates, as92//     it is the same as the one of its parameters. So its TypeBehind93//     method returns the right type, and so no need to pass it as model94//     parameter. Note that the .(int) type assertion is still mandatory95//     to conform to the strict type checking.96//97// Without operator anchoring feature, the previous example would have98// been:99//100//	import (101//	  "testing"102//103//	  "github.com/maxatome/go-testdeep/td"104//	)105//106//	func TestFunc(tt *testing.T) {107//	  got := Func()108//109//	  t := td.NewT(tt)110//	  t.Cmp(got, td.Struct(&MyStruct{Name: "Bob"},111//	    td.StructFields{112//	    "Details": td.Struct(&MyDetails{},113//	      td.StructFields{114//	        "Nick": td.HasPrefix("Bobby"),115//	        "Age":  td.Between(40, 50),116//	      }),117//	  }))118//	}119//120// using two times the [Struct] operator to work around the strict type121// checking of golang.122//123// By default, the value returned by Anchor can only be used in the124// next [T.Cmp] or [T.CmpLax] call. To make it persistent across calls,125// see [T.SetAnchorsPersist] and [T.AnchorsPersistTemporarily] methods.126//127// See [T.A] method for a shorter synonym of Anchor.128//129// See also [T.AnchorsPersistTemporarily], [T.DoAnchorsPersist],130// [T.ResetAnchors], [T.SetAnchorsPersist] and [AddAnchorableStructType].131func (t *T) Anchor(operator TestDeep, model ...any) any {132	if operator == nil {133		t.Helper()134		t.Fatal(color.Bad("Cannot anchor a nil TestDeep operator"))135	}136	var typ reflect.Type137	if len(model) > 0 {138		if len(model) != 1 {139			t.Helper()140			t.Fatal(color.TooManyParams("Anchor(OPERATOR[, MODEL])"))141		}142		var ok bool143		typ, ok = model[0].(reflect.Type)144		if !ok {145			typ = reflect.TypeOf(model[0])146			if typ == nil {147				t.Helper()148				t.Fatal(color.Bad("Untyped nil value is not valid as model for an anchor"))149			}150		}151		typeBehind := operator.TypeBehind()152		if typeBehind != nil && typeBehind != typ {153			t.Helper()154			t.Fatal(color.Bad("Operator %s TypeBehind() returned %s which differs from model type %s. Omit model or ensure its type is %[2]s",155				operator.GetLocation().Func, typeBehind, typ))156		}157	} else {158		typ = operator.TypeBehind()159		if typ == nil {160			t.Helper()161			t.Fatal(color.Bad("Cannot anchor operator %s as TypeBehind() returned nil. Use model parameter to specify the type to return",162				operator.GetLocation().Func))163		}164	}165	nvm, err := t.Config.anchors.AddAnchor(typ, reflect.ValueOf(operator))166	if err != nil {167		t.Helper()168		t.Fatal(color.Bad(err.Error()))169	}170	return nvm.Interface()171}172// A is a synonym for [T.Anchor].173//174//	import (175//	  "testing"...

td_ptr.go

Source:td_ptr.go

...28//29//	num := 330//	td.Cmp(t, &num, td.Ptr(td.Between(3, 4)))31//32// TypeBehind method returns the [reflect.Type] of a pointer on val,33// except if val is a [TestDeep] operator. In this case, it delegates34// TypeBehind() to the operator and returns the [reflect.Type] of a35// pointer on the returned value (if non-nil of course).36//37// See also [PPtr] and [Shallow].38func Ptr(val any) TestDeep {39	p := tdPtr{40		tdSmugglerBase: newSmugglerBase(val),41	}42	vval := reflect.ValueOf(val)43	if !vval.IsValid() {44		p.err = ctxerr.OpBadUsage("Ptr", "(NON_NIL_VALUE)", val, 1, true)45		return &p46	}47	if !p.isTestDeeper {48		p.expectedValue = reflect.New(vval.Type())49		p.expectedValue.Elem().Set(vval)50	}51	return &p52}53func (p *tdPtr) Match(ctx ctxerr.Context, got reflect.Value) *ctxerr.Error {54	if p.err != nil {55		return ctx.CollectError(p.err)56	}57	if got.Kind() != reflect.Ptr {58		if ctx.BooleanError {59			return ctxerr.BooleanError60		}61		return ctx.CollectError(&ctxerr.Error{62			Message:  "pointer type mismatch",63			Got:      types.RawString(got.Type().String()),64			Expected: types.RawString(p.String()),65		})66	}67	if p.isTestDeeper {68		return deepValueEqual(ctx.AddPtr(1), got.Elem(), p.expectedValue)69	}70	return deepValueEqual(ctx, got, p.expectedValue)71}72func (p *tdPtr) String() string {73	if p.err != nil {74		return p.stringError()75	}76	if p.isTestDeeper {77		return "*<something>"78	}79	return p.expectedValue.Type().String()80}81func (p *tdPtr) TypeBehind() reflect.Type {82	if p.err != nil {83		return nil84	}85	// If the expected value is a TestDeep operator, delegate TypeBehind to it86	if p.isTestDeeper {87		typ := p.expectedValue.Interface().(TestDeep).TypeBehind()88		if typ == nil {89			return nil90		}91		// Add a level of pointer92		return reflect.New(typ).Type()93	}94	return p.expectedValue.Type()95}96type tdPPtr struct {97	tdSmugglerBase98}99var _ TestDeep = &tdPPtr{}100// summary(PPtr): allows to easily test a pointer of pointer value101// input(PPtr): ptr102// PPtr is a smuggler operator. It takes the address of the address of103// data and compares it to val.104//105// val depends on data type. For example, if the compared data is an106// **int, one can have:107//108//	num := 12109//	pnum = &num110//	td.Cmp(t, &pnum, td.PPtr(12)) // succeeds111//112// as well as an other operator:113//114//	num := 3115//	pnum = &num116//	td.Cmp(t, &pnum, td.PPtr(td.Between(3, 4))) // succeeds117//118// It is more efficient and shorter to write than:119//120//	td.Cmp(t, &pnum, td.Ptr(td.Ptr(val))) // succeeds too121//122// TypeBehind method returns the [reflect.Type] of a pointer on a123// pointer on val, except if val is a [TestDeep] operator. In this124// case, it delegates TypeBehind() to the operator and returns the125// [reflect.Type] of a pointer on a pointer on the returned value (if126// non-nil of course).127//128// See also [Ptr].129func PPtr(val any) TestDeep {130	p := tdPPtr{131		tdSmugglerBase: newSmugglerBase(val),132	}133	vval := reflect.ValueOf(val)134	if !vval.IsValid() {135		p.err = ctxerr.OpBadUsage("PPtr", "(NON_NIL_VALUE)", val, 1, true)136		return &p137	}138	if !p.isTestDeeper {139		pVval := reflect.New(vval.Type())140		pVval.Elem().Set(vval)141		p.expectedValue = reflect.New(pVval.Type())142		p.expectedValue.Elem().Set(pVval)143	}144	return &p145}146func (p *tdPPtr) Match(ctx ctxerr.Context, got reflect.Value) *ctxerr.Error {147	if p.err != nil {148		return ctx.CollectError(p.err)149	}150	if got.Kind() != reflect.Ptr || got.Elem().Kind() != reflect.Ptr {151		if ctx.BooleanError {152			return ctxerr.BooleanError153		}154		return ctx.CollectError(&ctxerr.Error{155			Message:  "pointer type mismatch",156			Got:      types.RawString(got.Type().String()),157			Expected: types.RawString(p.String()),158		})159	}160	if p.isTestDeeper {161		return deepValueEqual(ctx.AddPtr(2), got.Elem().Elem(), p.expectedValue)162	}163	return deepValueEqual(ctx, got, p.expectedValue)164}165func (p *tdPPtr) String() string {166	if p.err != nil {167		return p.stringError()168	}169	if p.isTestDeeper {170		return "**<something>"171	}172	return p.expectedValue.Type().String()173}174func (p *tdPPtr) TypeBehind() reflect.Type {175	if p.err != nil {176		return nil177	}178	// If the expected value is a TestDeep operator, delegate TypeBehind to it179	if p.isTestDeeper {180		typ := p.expectedValue.Interface().(TestDeep).TypeBehind()181		if typ == nil {182			return nil183		}184		// Add 2 levels of pointer185		return reflect.New(reflect.New(typ).Type()).Type()186	}187	return p.expectedValue.Type()188}...

td_lax.go

Source:td_lax.go

...31// Note that in the latter case, [CmpLax] could be used as well:32//33//	td.CmpLax(t, floatValue, bw)34//35// TypeBehind method returns the greatest convertible or more common36// [reflect.Type] of expectedValue if it is a base type (bool, int*,37// uint*, float*, complex*, string), the [reflect.Type] of38// expectedValue otherwise, except if expectedValue is a [TestDeep]39// operator. In this case, it delegates TypeBehind() to the operator.40func Lax(expectedValue any) TestDeep {41	c := tdLax{42		tdSmugglerBase: newSmugglerBase(expectedValue),43	}44	if !c.isTestDeeper {45		c.expectedValue = reflect.ValueOf(expectedValue)46	}47	return &c48}49func (l *tdLax) Match(ctx ctxerr.Context, got reflect.Value) *ctxerr.Error {50	ctx.BeLax = true51	return deepValueEqual(ctx, got, l.expectedValue)52}53func (l *tdLax) HandleInvalid() bool {54	return true // Knows how to handle untyped nil values (aka invalid values)55}56func (l *tdLax) String() string {57	return "Lax(" + util.ToString(l.expectedValue) + ")"58}59func (l *tdLax) TypeBehind() reflect.Type {60	// If the expected value is a TestDeep operator, delegate TypeBehind to it61	if l.isTestDeeper {62		return l.expectedValue.Interface().(TestDeep).TypeBehind()63	}64	// For base types, returns the greatest convertible or more common one65	switch l.expectedValue.Kind() {66	case reflect.Invalid:67		return nil68	case reflect.Bool:69		return reflect.TypeOf(false)70	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:71		return reflect.TypeOf(int64(0))72	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:73		return reflect.TypeOf(uint64(0))74	case reflect.Float32, reflect.Float64:75		return reflect.TypeOf(float64(0))76	case reflect.Complex64, reflect.Complex128:...

TypeBehind

Using AI Code Generation

1import (2func main() {3	t := reflect.TypeOf(x)4	fmt.Println("Type of x is ", t)5	fmt.Println("Type of x is ", t.Kind())6	fmt.Println("Type of x is ", t.Name())7	fmt.Println("Type of x is ", t.String())8}9import (10func main() {11	t := reflect.TypeOf(x)12	fmt.Println("Type of x is ", t)13	fmt.Println("Type of x is ", t.Kind())14	fmt.Println("Type of x is ", t.Name())15	fmt.Println("Type of x is ", t.String())16	fmt.Println("Type of x is ", t.Kind().String())17}18import (19func main() {20	t := reflect.TypeOf(x)21	fmt.Println("Type of x is ", t)22	fmt.Println("Type of x is ", t.Kind())23	fmt.Println("Type of x is ", t.Name())24	fmt.Println("Type of x is ", t.String())25	fmt.Println("Type of x is ", t.Kind().String())26	fmt.Println("Type of x is ", t.Kind().String())27}28import (29func main() {30	t := reflect.TypeOf(x)31	fmt.Println("Type of x is ", t)32	fmt.Println("Type of x is ", t.Kind())33	fmt.Println("Type of x is ", t.Name())34	fmt.Println("Type of x is ", t.String())35	fmt.Println("Type of x is ", t.Kind().String())36	fmt.Println("Type

TypeBehind

Using AI Code Generation

1import (2func main() {3    td = NewTypeDescriptor(reflect.TypeOf(5))4    fmt.Println(td.TypeBehind())5    td = NewTypeDescriptor(reflect.TypeOf(5.6))6    fmt.Println(td.TypeBehind())7    td = NewTypeDescriptor(reflect.TypeOf("Hello"))8    fmt.Println(td.TypeBehind())9    td = NewTypeDescriptor(reflect.TypeOf([]int{1, 2, 3}))10    fmt.Println(td.TypeBehind())11    td = NewTypeDescriptor(reflect.TypeOf([]string{"Hello", "World"}))12    fmt.Println(td.TypeBehind())13    td = NewTypeDescriptor(reflect.TypeOf([]float64{1.1, 2.2, 3.3}))14    fmt.Println(td.TypeBehind())15    td = NewTypeDescriptor(reflect.TypeOf([]interface{}{1, 2.2, "Hello"}))16    fmt.Println(td.TypeBehind())17}18interface {}

TypeBehind

Using AI Code Generation

1import (2func main() {3 t = reflect.TypeOf(3)4 fmt.Println("type:", t)5 fmt.Println("type behind:", t.TypeBehind())6}

TypeBehind

Using AI Code Generation

1import "fmt"2type td struct {3}4func (t td) TypeBehind() string {5}6func main() {7    t := td{"John", 25}8    fmt.Println(t.TypeBehind())9}10import "fmt"11type td struct {12}13func (t td) TypeBehind() string {14}15func main() {16    t := td{"John", 25}17    fmt.Println(t.TypeBehind())18}19import "fmt"20type td struct {21}22func (t td) TypeBehind() string {23}24func main() {25    t := td{"John", 25}26    fmt.Println(t.TypeBehind())27}28import "fmt"29type td struct {30}31func (t td) TypeBehind() string {32}33func main() {34    t := td{"John", 25}35    fmt.Println(t.TypeBehind())36}37import "fmt"38type td struct {39}40func (t td) TypeBehind() string {41}42func main() {43    t := td{"John", 25}44    fmt.Println(t.TypeBehind())45}

TypeBehind

Using AI Code Generation

1import (2type TD struct {3}4func (t *TD) TypeBehind() reflect.Type {5	return reflect.TypeOf(t)6}7func main() {8	td := TD{}9	fmt.Println(td.TypeBehind().Name())10}

TypeBehind

Using AI Code Generation

1import (2type td struct {3}4func main() {5	fmt.Println(t.TypeBehind(i))6	fmt.Println(t.TypeBehind(s))7}8func (t td) TypeBehind(i interface{}) string {

TypeBehind

Using AI Code Generation

1import (2func main() {3    td := xlsx.NewTealeg()4    fmt.Println(td.TypeBehind("Employee"))5}6import (7func main() {8    td := xlsx.NewTealeg()9    fmt.Println(td.TypeBehind("Employee"))10}11import (12func main() {13    td := xlsx.NewTealeg()14    fmt.Println(td.TypeBehind("Employee"))15}16import (17func main() {18    td := xlsx.NewTealeg()19    fmt.Println(td.TypeBehind("Employee"))20}21import (22func main() {23    td := xlsx.NewTealeg()24    fmt.Println(td.TypeBehind("Employee"))25}26import (27func main() {28    td := xlsx.NewTealeg()29    fmt.Println(td.TypeBehind("Employee"))30}31import (32func main() {33    td := xlsx.NewTealeg()34    fmt.Println(td.TypeBehind("Employee"))35}36import (

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