`shortest_match` does not match *shortest*

[mina86]

What version of regex are you using?

1.4.3

Describe the bug at a high level.

The name shortest_match is misleading. It suggests the method will return shortest possible match. In reality that’s not the case. While I accept that it may be infeasible to change the code to make such guarantee, the name of the method should be changed. fastest_match? match_end?

What are the steps to reproduce the behavior?

extern crate regex;

use regex::Regex;

fn main() {
    println!("{}", Regex::new("ab|a").unwrap().shortest_match("ab").unwrap());
}

What is the actual behavior?

Prints 2.

What is the expected behavior?

Prints 1.

[BurntSushi]

Indeed. A better name I think is leftmost_first, but it is a bit more arcane I think.

With that said, I am not sure that the current behavior is correct either. It requires an investigation. I would naively assume that your program prints 1.