As far as trying in PRQL/prqlc-r#78, I think this is working fine.

But obviously tests on these should be added here.
I am not familiar with Rust testing and would like to add tests at another time...

I am not familiar with Rust testing

It's surprisingly easy!

We can just have something like this, in the file:

#[cfg(test)]
mod test {
use insta::assert_debug_snapshot;

#[test]
fn test_target_from_str() {

    assert_debug_snapshot!(Target::from_str("sql.postgres".to_string()), @"");

    assert!(Target::from_str("sql.poostgres".to_string().is_err());
}
}

...then running cargo insta test --accept will fill out the @ string.