[PATCH 10 of 10 V5] pager: do not read from environment variable

[Ryan McElroy]

On 3/27/17 7:02 AM, Jun Wu wrote:
> # HG changeset patch
> # User Jun Wu <quark at fb.com>
> # Date 1490589827 25200
> #      Sun Mar 26 21:43:47 2017 -0700
> # Node ID 5641b83eff817bdb0d7adeb24c7383653ef15617
> # Parent  a354f13a30b93943635224fcd90f43019241e23e
> pager: do not read from environment variable

This series looks good to me. It's a great behavior improvement and 
cleanup that is well-executed.

I'll mark as pre-reviewed in patchwork. I have a few small nits I'll 
send out shortly but they don't affect the result and could easily be 
follow-ups and shouldn't block queuing in my opinion.

>
> $PAGER is converted to the pager.pager config item. So it's no longer
> necessary to read $PAGER in ui.pager().
>
> diff --git a/mercurial/ui.py b/mercurial/ui.py
> --- a/mercurial/ui.py
> +++ b/mercurial/ui.py
> @@ -850,12 +850,6 @@ class ui(object):
>               return
>   
> -        # TODO: add a "system defaults" config section so this default
> -        # of more(1) can be easily replaced with a global
> -        # configuration file. For example, on OS X the sane default is
> -        # less(1), not more(1), and on debian it's
> -        # sensible-pager(1). We should probably also give the system
> -        # default editor command similar treatment.
> -        envpager = encoding.environ.get('PAGER', 'more')
> -        pagercmd = self.config('pager', 'pager', envpager)
> +        fallbackpager = 'more'
> +        pagercmd = self.config('pager', 'pager', fallbackpager)
>           if not pagercmd:
>               return
>