Is it possible to return a ValidationErrors from a Keyword implementation?

[hdonnay]

I'd like to implement a keyword that implements some custom "linting" checks, but would like to have all the checks that failed reported. It seems like there's currently no way to return multiple errors.

Alternatively, having some mechanism to return multiple Keyword implementations would achieve the same thing.

[Stranger6667]

Hi!

I think it should be possible by extending the trait with some iter_errors method that by default returns "once" with "validate" result and connect it with other machinery

[hdonnay]

as in something like the following? (I did not check that the lifetimes work)

pub trait Keyword: Send + Sync {
    /// Validate an instance against this custom keyword.
    ///
    /// Use [`ValidationError::custom`] for error messages. Path information
    /// (`instance_path` and `schema_path`) is filled in automatically.
    ///
    /// # Errors
    ///
    /// Returns a [`ValidationError`] if the instance is invalid.
    fn validate<'i>(&self, instance: &'i Value) -> Result<(), ValidationError<'i>>;

    /// Check validity without collecting error details.
    fn is_valid(&self, instance: &Value) -> bool;

    /// ...
    fn iter_errors<'i>(&self, instance: &'i Value) -> impl Iterator<Item=Result<(), ValidationError<'i>>>{
        std::iter::once_with(|| self.validate(instance))
    }
}

[Stranger6667]

yep, I was thinking about this one exactly