[PATCH] identify: avoid a crash when given '-r wdir()'

[Yuya Nishihara]

On Sun, 28 Jun 2015 21:40:09 -0400, Matt Harbison wrote:
> # HG changeset patch
> # User Matt Harbison <matt_harbison at yahoo.com>
> # Date 1435531198 14400
> #      Sun Jun 28 18:39:58 2015 -0400
> # Node ID 6f1a661262ebb3281f707642447887deaafafc38
> # Parent  601770f5da477240954670d51f5ea11caa40dc20
> identify: avoid a crash when given '-r wdir()'
> 
> The crash was 'NoneType is not subscriptable' in hexfunc(ctx.node()), because
> the node for wdir() is None.  This can be avoided simply by detecting 'wdir()'
> and taking the existing path for no given revision.
> 
> diff --git a/mercurial/commands.py b/mercurial/commands.py
> --- a/mercurial/commands.py
> +++ b/mercurial/commands.py
> @@ -4064,6 +4064,12 @@
>              if bm:
>                  output.append(bm)
>      else:
> +        if rev:
> +            # If wdir() is given, translate back to None
> +            ctx = scmutil.revsingle(repo, rev)
> +            if ctx.rev() is None:
> +                rev = None
> +
>          if not rev:
>              ctx = repo[None]

Perhaps we can simply do

  ctx = scmutil.revsingle(repo, rev, None)
  if ctx.rev() is None:
      ...
  else:
      ...