Is there a tag like len_if

[picone]

My case:

We should ensure the Values must has value if Enabled is true.

struct Foo {
  Enabled bool
  Values []string `validate:"required_if=Enabled true,dive,oneof=a b c"`
}

If the Values is nil, the validator work well, but if the Values is an empty slice, it can pass the validator.

I've read the docs, I think it work as expected:

For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

So, I think we should add a tag like len_if?

struct Foo {
  Enabled bool
  Values []string `validate:"len_if=Enabled true 0,dive,oneof=a b c"`
}