Re: Mac OS Sierra tab feature breaks C-x 5 2

[Alan Third <alan@idiocy.org>]

On Fri, Jul 07, 2017 at 12:05:32AM +0900, Jean-Christophe Helary wrote:
> 
> > On Jul 6, 2017, at 23:35, Alan Third <athird@googlemail.com> wrote:
> 
> > I've just realised that we're using a build time version check,
> > and the Emacs for macOS releases are built on an older version of
> > macOS... I'm not sure what the best solution here is...
> 
> Is the result very different depending on the version of macOS?
> What's the version you are building on?

I build on Sierra.

We have this code

    #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12
      [win setTabbingMode: NSWindowTabbingModeDisallowed];
    #endif

in initFrameFromEmacs in nsterm.m. The idea being that since this code
only works in 10.12 and up, we only include it when Emacs is compiled
on 10.12. This might be why you’re not seeing the broken behaviour.

I believe that the emacsformacosx builds are built on 10.9 or 10.10 or
something? I can’t remember exactly. That means this code is not
included.

We can make it a run time check, which would look something like

    if ([win respondsToSelector: @selector(setTabbingMode)])
      [win setTabbingMode: NSWindowTabbingModeDisallowed];

but this will throw up compiler warnings on pre‐Sierra versions of
macOS. I guess that’s maybe just the price to be paid.
-- 
Alan Third