String without max_length annotation is compiling

[myOmikron]

Give the following struct definition:

#[derive(Model)]
pub(crate) struct Trainer {
    #[rorm(id)]
    pub(crate) id: i64,
    #[rorm(on_delete = "Cascade")]
    pub(crate) user: ForeignModel<User>,
    pub(crate) trainer_name: String,
    pub(crate) trainer_sprite: i16,
    #[rorm(default = 0)]
    pub(crate) money: i32,
    #[rorm(field = "TrainerFriend::F.origin")]
    pub(crate) friends: BackRef<TrainerFriend>,
}

When exporting the .models.json: The following snippet is produced:
{"Name":"trainer_name","Type":"varchar","Annotations":[{"Type":"not_null"}]}

Intended behavior:
There should be a compile time error when trying to use a String without a max_length annotation