Macro assertables::assertable_f_err_string_eq

macro_rules! assertable_f_err_string_eq {
    ($function:path, $left:expr, $right:expr $(,)?) => { ... };
    ($function:path, $left:expr, $right:expr, $($arg:tt)+) => { ... };
}

Assert one function ok() is equal to another function ok().

• When true, return Ok(()).

• Otherwise, return Err with a message and the values of the expressions with their debug representations.

Examples

fn example_digit_to_string(i: isize) -> Result<String, String> {
    match i {
        0..=9 => Ok(format!("{}", i)),
        _ => Err(format!("{:?} is out of range", i)),
    }
}
 
let x = assertable_f_err_string_eq!(example_digit_to_string, 10, 10);
//-> Ok(())
assert_eq!(x.unwrap(), ());

let x = assertable_f_err_string_eq!(example_digit_to_string, 10, 20);
//-> Err("…")
// assertable failed: `assertable_f_err_string_eq!(function, left, right)`
//      function: `\"example_digit_to_string\"`,
//    left input: `10`,
//   right input: `20`,
//   left output: `\"10 is out of range\"`,
//  right output: `\"20 is out of range\"`
assert_eq!(x.unwrap_err(), "assertable failed: `assertable_f_err_string_eq!(function, left, right)`\n     function: `\"example_digit_to_string\"`,\n   left input: `10`,\n  right input: `20`,\n  left is err: `true`,\n right is err: `true`,\n  left output: `\"10 is out of range\"`,\n right output: `\"20 is out of range\"`".to_string());

This macro has a second form where a custom message can be provided.