FieldError.Field() doesn't work

[bambulin]

• [x] I have looked at the documentation here first?
• [x] I have looked at the examples provided that may showcase my question here?

Package version:

v10

Issue, Question or Enhancement:

Method Field() of FieldError doesn't work according to documentation:

// Field returns the fields name with the tag name taking precedence over the
// field's actual name.
//
// eq. JSON name "fname"
// see StructField for comparison
Field() string 

Code sample, to showcase or reproduce:

type Struct struct {
	Field string `json:"json_field" validate:"required"`
}

func TestField(t *testing.T) {
	v := validator.New()
	s := &Struct{}
	err := v.Struct(s)
	valErrs := err.(validator.ValidationErrors)
	requiredErr := valErrs[0]
	fmt.Println(requiredErr.Field())
}

The output is Field, according to documentation it should be json_field

[grandeto]

I confirm this behave

However this should do the trick

v := validator.New()
v.RegisterTagNameFunc(func(fld reflect.StructField) string {
	name := strings.SplitN(fld.Tag.Get("json"), ",", 2)[0]

        if name == "-" {
	        return ""
        }

	return name
})

ref:

• https://github.com/go-playground/validator/blob/master/validator_test.go#L8285-L8326
• https://pkg.go.dev/github.com/go-playground/validator/v10#Validate.RegisterTagNameFunc

[toudi]

I stumbled upon this issue today and if anybody needs to use it in gin framework, here's how:

router := gin.Default()

if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
	v.RegisterTagNameFunc(func(fld reflect.StructField) string {
		name := strings.SplitN(fld.Tag.Get("json"), ",", 2)[0]

		if name == "-" {
			return ""
		}

		return name
	})
}

works like a charm, thanks a lot @grandeto !