nil pointer dereference attempting to override input Body contentType with application/x-www-form-urlencoded

[ScottCUSA]

Hello,

I have been trying to implement an endpoint which accepts and validates application/x-www-form-urlencoded using some of the examples in previous issues for reference. I have the endpoint working. However, the OpenAPI docs lists it accepts both application/json and application/x-www-form-urlencoded.

I'd like to remove application/json support if possible. To do this I tried adding a contentType overwrite tag to the the Body struct in the handler func's input struct.

func(ctx context.Context, input *struct {
	Body *Request `contentType:"application/x-www-form-urlencoded"`
}) (*Resp, error) {
	return &Resp{Body: input.Body}, nil
})

This resolves the docs reporting it accepts json but it causes the huma validator to panic from a nil pointer dereference when I submit a request:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x5dfc65]

goroutine 1 [running]:
github.com/danielgtaylor/huma/v2.Validate({0x6e3800, 0xc000026540}, 0x21?, 0xc00006c8e0, 0x1, {0x631ce0, 0xc000017d70}, 0xc000010420)
   /tmp/gopath2204094610/pkg/mod/github.com/danielgtaylor/huma/[email protected]/validate.go:362 +0xa5
github.com/danielgtaylor/huma/v2.Register[...].func1()
   /tmp/gopath2204094610/pkg/mod/github.com/danielgtaylor/huma/[email protected]/huma.go:1346 +0x1605
github.com/danielgtaylor/huma/v2/adapters/humago.(*goAdapter).Handle.func1({0x6e3368, 0xc000026780}, 0xc000143400)
   /tmp/gopath2204094610/pkg/mod/github.com/danielgtaylor/huma/[email protected]/adapters/humago/humago.go:145 +0xa2
net/http.HandlerFunc.ServeHTTP(0xc000196000?, {0x6e3368?, 0xc000026780?}, 0xc000173a68?)
   /usr/local/go-faketime/src/net/http/server.go:2220 +0x29
net/http.(*ServeMux).ServeHTTP(0x654900?, {0x6e3368, 0xc000026780}, 0xc000143400)
   /usr/local/go-faketime/src/net/http/server.go:2747 +0x1ca
main.main()
   /tmp/sandbox1666713405/prog.go:84 +0x6a6

Is there a better way to do what I need?

Example code:
https://go.dev/play/p/ul4rPk-eh6r