D5945: rust: itering less on MissingAncestors.bases for max()

[kevincox (Kevin Cox)]

kevincox added inline comments.

INLINE COMMENTS

> ancestors.rs:347
>          }
> -
> -        let max_bases =
> -            bases_visit.iter().cloned().max().unwrap_or(NULL_REVISION);
> -        let max_revs =
> -            revs_visit.iter().cloned().max().unwrap_or(NULL_REVISION);
> -        let start = max(max_bases, max_revs);
> +        let max_revs = revs_visit.iter().cloned().max().unwrap();
> +        let start = max(self.max_base, max_revs);

You are doing an empty check and an unwrap. I think it would be nice to combine these to make it obvious that there is no panic chance here.

  let max_revs = revs_visit.iter().cloned().max();
  let max_revs = match max_revs {
    Some(max) => max,
    None => return Ok(Vec::new()),
  };

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D5945

To: gracinet, #hg-reviewers, kevincox
Cc: durin42, kevincox, mercurial-devel