[PATCH] show: config option to register aliases for views

[Yuya Nishihara]

On Sun, 25 Jun 2017 22:26:52 -0700, Gregory Szorc wrote:
> # HG changeset patch
> # User Gregory Szorc <gregory.szorc at gmail.com>
> # Date 1498454437 25200
> #      Sun Jun 25 22:20:37 2017 -0700
> # Node ID 6546ab6d7a9aaa4266d1decf3da1501153be796b
> # Parent  ef46d432e2e4cfecafb1faa4765254bf0650d4ef
> show: config option to register aliases for views
> 
> As part of using `hg show` in my daily workflow, I've found it slightly
> annoying to have to type full view names, complete with a space. I've
> locally registered an alias for "swork = show work."
> 
> I think others will have this same complaint and could benefit from
> some automation to streamline the creation of aliases. So, this
> commit introduces a config option that allows `hg show` views to be
> automatically aliased using a given prefix. e.g. a value of "s"
> will automatically register "swork" and "sbookmarks." Multiple
> values can be given for ultimate flexibility. This arguably isn't
> needed now. But since we don't register aliases if there will be
> a collision and we're bound to have a collision, it makes sense to
> allow multiple prefixes so specific views can avoid collisions by
> using different prefixes.

I think this change is okay. (I don't queue it now just because it's late.)

Somewhat related to this, I've lost why we decided to make "hg show <cmd>"
at the cost of managing sub-sub commands. If we want a shorter command name,
I think "hg work" is even better.

> +def extsetup(ui):
> +    # Alias `hg <prefix><view>` to `hg show <view>`.
> +    for prefix in ui.configlist('commands', 'show.aliasprefix'):
> +        for view in showview._table:
> +            name = '%s%s' % (prefix, view)
> +
> +            choice, allcommands = cmdutil.findpossible(name, commands.table,
> +                                                       strict=True)
> +
> +            # This alias is already a command name. Don't set it.
> +            if name in choice:
> +                continue
> +
> +            # Same for aliases.
> +            if ui.config('alias', name):
> +                continue
> +
> +            ui.setconfig('alias', name, 'show %s' % view, source='show')

Setting config in ui/extsetup() doesn't work in general, but we're lucky that
addaliases() takes lui not ui.