[PATCH] dagop: raise ProgrammingError if stopdepth<=0

[Yuya Nishihara]

On Fri, 23 Jun 2017 22:48:23 -0700, Martin von Zweigbergk via Mercurial-devel wrote:
> # HG changeset patch
> # User Martin von Zweigbergk <martinvonz at google.com>
> # Date 1498281322 25200
> #      Fri Jun 23 22:15:22 2017 -0700
> # Node ID d654eefeefdd3df493fa777cbcfe423f17d9d500
> # Parent  fac9941bd542e3621082b157fb2f3aff09cfb1b7
> dagop: raise ProgrammingError if stopdepth<=0
> 
> revset.py should never send such a value.
> 
> diff --git a/mercurial/dagop.py b/mercurial/dagop.py
> --- a/mercurial/dagop.py
> +++ b/mercurial/dagop.py
> @@ -33,7 +33,7 @@
>      if stopdepth is None:
>          stopdepth = _maxlogdepth
>      if stopdepth <= 0:
> -        return
> +        raise error.ProgrammingError('negative stopdepth')

I think stopdepth = 0 is valid on API level, so I want to change the condition
to stopdepth < 0. I'll update it in flight if you agree.