D1581: rust: implementation of `hg`

[ruuda (Ruud van Asseldonk)]

ruuda added a comment.


  Awesome! I have just a few things that could be written more briefly.

INLINE COMMENTS

> build.rs:39
> +    let script = "import sysconfig; \
> +c = sysconfig.get_config_vars(); \
> +print('SEPARATOR STRING'.join('%s=%s' % i for i in c.items()))";

You can safely indent those, leading whitespace on the continuation line will be stripped from the string literal.

> build.rs:107
> +            None => false,
> +        };
> +

There is no need to match:

  let result = config.config.get(*key) == Some("1");

Or using assert as @kevincox recommends:

  assert_eq!(config.config.get(*key), Some("1"), "Detected ...");

> main.rs:187
> +                Err(255)
> +            }
> +            Ok(()) => Ok(()),

There exists `Result::map_err` for this:

  result = run_py(&env, py).map_err(|err| {
      err.print(py);
      255
  });

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D1581

To: indygreg, #hg-reviewers, yuja, durin42
Cc: ruuda, kevincox, cramertj, yuja, quark, durin42, dlax, mercurial-devel