Re: src/nsterm.m: fix window tabbing on macOS

[Alan Third]

On Tue, May 11, 2021 at 03:45:08PM +1000, Paul W. Rankin via Emacs development 
discussions. wrote:
> On 2021-05-11 05:53, Alan Third wrote:
> > On Sat, May 08, 2021 at 10:27:13PM +1000, Paul W. Rankin wrote:
> > I reckon this is probably OK, but I'll leave it a bit longer to see if
> > anyone else has an opinion.
> 
> If I'm not mistaken, it is the fourth commandment of emacs-devel that
> someone must raise an objection. Especially if the change does not affect
> them.

Indeed, then argue the point to the death. :)

> > That location really doesn't much sense! Certainly explains why I've
> > never seen it before. :)
> > 
> > This is really my lastremaining concern, that it's such an obscure
> > setting that we'll get a lot of bug reports about Emacs-doing-tabs
> > when-I-don't-want-it-to. I'm not sure there's a good solution to that
> > other than perhaps putting a note in the NS port documentation (which
> > afaict nobody ever reads anyway).
> 
> You are correct. I only looked at the nextstep/README file today.
> 
> Given that tabs look much a part of the macOS window system I think/hope a
> person's first assumption would be that it's an Apple thing and hopefully
> first burn out their ire on Apple forums/reddits/etc. Nevertheless, we
> shouldn't inhibit all for the failings of a few.

Yes, I suppose we could put it in NEWS and hope that enough people see
it there to cover us in places like reddit.

> The only thing that's a little weird is that this tab bar is not visible
> when in full screen, requiring moving the mouse up to reveal it. It would
> clearer what's happening if the tab bar behaved more like Terminal.app when
> in full screen: opening more than a single tab keeps the tab bar visible (in
> full screen or windowed).

Isn't that how all the window chrome works in fullscreen? Do we do
some special thing to hide the toolbar? Perhaps we should rethink that
(although enough people run in fullscreen all the time that I suspect
that change would be genuinely contentious).

> Apple's documentation on this is very thin, so I doubt it's a simple boolean
> switch: https://developer.apple.com/documentation/appkit/nswindowtabgroup

I remember looking into whether we could leverage the tab bar for our
built-in tab stuff, but it's a disappointingly featureless API.

> > BTW, is there an advantage to explicitly enabling the default setting
> > over just removing the code that disables it?
> 
> Sorry I am unqualified to offer an opinion here, other than if someone wants
> to change it the code is already there for them to easily make the change
> and rebuild Emacs.

If you just remove it completely does it do anything different from
your patch?

> Tangentially, this lead me to read a little about GNUstep. Does GNUstep
> provide the same kind of tabbing as macOS?

No, not to my knowledge. It may eventually, but unless someone's very
keen to implement it GNUstep tends to lag quite far behind the macOS
APIs.
-- 
Alan Third