bug#24164: 25.1.50; `global-linum-mode' with text scaling

bug#24164: 25.1.50; `global-linum-mode' with text scaling

[Drew Adams]

emacs -Q

(global-linum-mode t)

Increase text size several times: `C-x = = = = = ='.

Decrease it several times: `C-x - - - - - -'.

Each time you increase, the space for the line numbers, to the left of
the fringe, is enlarged.  When you decrease, that space is not reduced.
The margin should reflect the apparent size of the line numbers, not
some previous, larger size


In GNU Emacs 25.1.50.1 (i686-pc-mingw32)
 of 2015-12-10
Repository revision: 6148555ee5a3d0139ae517803718b3e0357933c7
Windowing system distributor 'Microsoft Corp.', version 6.1.7601
Configured using:
 'configure --prefix=/c/Devel/emacs/snapshot/trunk --enable-checking=yes
 --enable-check-lisp-object-type --without-compress-install 'CFLAGS=-Og
 -ggdb3' LDFLAGS=-Lc:/Devel/emacs/lib 'CPPFLAGS=-DGC_MCHECK=1
 -Ic:/Devel/emacs/include''

bug#24164: 25.1.50; `global-linum-mode' with text scaling

[Lars Ingebrigtsen]

Drew Adams <drew.adams@oracle.com> writes:

> emacs -Q
>
> (global-linum-mode t)
>
> Increase text size several times: `C-x = = = = = ='.
>
> Decrease it several times: `C-x - - - - - -'.
>
> Each time you increase, the space for the line numbers, to the left of
> the fringe, is enlarged.  When you decrease, that space is not reduced.
> The margin should reflect the apparent size of the line numbers, not
> some previous, larger size

Confirmed.  However, this is the result of the following change:

commit b92307f6708f9abff0b2ac242fe4b668232a9153
Author: João Távora <joaotavora@gmail.com>
Date:   Tue Nov 17 22:23:59 2015 +0000

    linum-mode plays more nicely with other margin-setting extensions
    
    linum.el will only modify the left margin if it needs to, and will
    only reset the it back to 0 if it guesses that no-one has touched that
    margin in the meantime.
    
    As such, this is a more of a workaround than an actual fix, but fixes
    the problems described in bug#20674 regarding the interaction with
    modes such as darkroom-mode and olivetti-mode.
    
    A similar fix was commited to nlinum.el in ELPA.git's
    e7f5f549fbfb740b911fb7f33b42381ecece56d8
    
    * linum.el (linum-delete-overlays): Restore margins more
    criteriously.
    (linum-update-window): Set margins more criteriously.

From the discussion in that bug report, it seems the consensus is that
there's no real way to fix this -- except not using linum.el.  By now
Emacs has native line number support, so the issue is moot-ish, and I'm
closing this bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no