the trait `std::error::Error` is not implemented for `digest_auth::error::Error` #3

In 0.1.x versions, we ware able to use ? operator on respond() method if function return type was Result<_, Box<dyn Error>>.

In version 0.2.0 it looks like digest_auth::error::Error is not convertible to Box<dyn Error> and it started throwing errors.

Before, the functions returned failure::Fallible<_>, now they return a custom Error, and I removed failure as a dependency.

Do you think there's something I should add to make it work better?

It would be nice to have it compatible with:

fn foo() -> Result<(), Box<dyn Error>> {
   (...)
        let authorization = digest_auth::parse(www_authenticate)?
            .respond(
                &digest_auth::AuthContext::new(
                    &self.login,
                    &self.password,
                    uri.as_str(),
                )
            )?.to_header_string();
   (...)
}

It was super ok for version 0.1.x, now it won't compile with errors as on topic.

Won't that be enough and easy to just implement this trait: https://doc.rust-lang.org/nightly/std/error/trait.Error.html for your custom error? I think you will need to implement just one method - source() that will probably just return None;

yep, I think that's it, I thought it'll be auto-implemented if you have Display and Debug. I'll add a unit test to check for this compatibility

If something is Display and Debug it won't necessarily be Error ;) For example IpAddr. I don't think it could be used as error.

of course, it makes sense now.

Please check if version 0.2.1 fixes the problem.

There's some other changes in v0.2, namely AuthContext now uses Cows, but the constructor should be backward compatible. It also implements parsing and display for both headers, so it should be usable server-side too.

Works like charm