bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Drew Adams]

emacs -Q

(defcustom foo '([next]) "" :type '(repeat sexp) :group 'edit)

M-x customize-option foo

In the edit field, try to select the current value, which is `[next]'.

Try to select it by dragging the mouse from start (left) to end (right).
As soon as the mouse passes the last char, to select it too, the
selection highlight disappears.

Try to select it using the keyboard to define the region: Put the cursor
before the `[' and hit `C-SPC'.  Then use `C-e' to move the cursor past
the `]'.  No region highlighting.  Try again, this time using `C-f' to
advance across the text.  As soon as you move past the `]', the region
highlighting disappears.

Users should have highlighting that shows them what text is selected -
all of that text, including the last character.  This is a regression
from Emacs 24.3, where selection worked normally.


In GNU Emacs 24.3.50.1 (i686-pc-mingw32)
 of 2014-02-02 on ODIEONE
Bzr revision: 116242 rudalics@gmx.at-20140202130041-n967dw77nw7ztvy9
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=/c/Devel/emacs/binary --enable-checking=yes,glyphs
 'CFLAGS=-O0 -g3' LDFLAGS=-Lc:/Devel/emacs/lib
 CPPFLAGS=-Ic:/Devel/emacs/include'

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Eli Zaretskii]

> Date: Thu, 6 Feb 2014 19:31:18 -0800 (PST)
> From: Drew Adams <drew.adams@oracle.com>
> 
> emacs -Q
> 
> (defcustom foo '([next]) "" :type '(repeat sexp) :group 'edit)
> 
> M-x customize-option foo
> 
> In the edit field, try to select the current value, which is `[next]'.
> 
> Try to select it by dragging the mouse from start (left) to end (right).
> As soon as the mouse passes the last char, to select it too, the
> selection highlight disappears.
> 
> Try to select it using the keyboard to define the region: Put the cursor
> before the `[' and hit `C-SPC'.  Then use `C-e' to move the cursor past
> the `]'.  No region highlighting.  Try again, this time using `C-f' to
> advance across the text.  As soon as you move past the `]', the region
> highlighting disappears.
> 
> Users should have highlighting that shows them what text is selected -
> all of that text, including the last character.  This is a regression
> from Emacs 24.3, where selection worked normally.

If I highlight inside the edit field, everything works as expected.
That is instead of

  Put the cursor before the `[' and hit `C-SPC'

I do

  Put the cursor ON the `[' and hit `C-SPC'

then I get the expected behavior.

What is the purpose of highlighting outside of the edit field?

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Drew Adams]

> If I highlight inside the edit field, everything works as expected.
> That is instead of
> 
>   Put the cursor before the `[' and hit `C-SPC'
> 
> I do Put the cursor ON the `[' and hit `C-SPC'

That is what I meant.  I should have said "put _point_ before..."
or "put the cursor on...".

> then I get the expected behavior.

This is very weird.  When I try now, I do not see the bug.
Last night it was entirely reproducible, from emacs -Q.

The behavior I saw was that selecting the entire text in the
edit field unhighlighted the selection.  IOW, selecting the
last char in the field caused unhighlighting.

No matter how I tried to select all of the text in the field,
selecting the last char made the highlighting disappear.
That was the bug I tried to report.  For example, just
double-clicking the `[', which selects the whole text `[next]',
did not highlight the selection (perhaps it highlighted then
unhighlighted it).

The text was in fact selected, as I tested by yanking it.
But the selection was not highlighted if it included the last
char.

> What is the purpose of highlighting outside of the edit field?

To be clear, I never tried to select beyond the last char.
I was only selecting all of the text in the field, _including_
the last char.  For example, C-SPC followed by <right>...
until the cursor moved past the last char, to select it.

But as I say, for some reason I cannot repro the bug this
morning.  I will keep an eye out, to see if it happens again.
But what is weird is that it was reproducible over and over
last night, but not now.

And I in fact still have an Emacs session (but with my setup,
not from emacs -Q) that shows the bugged behavior now.
I tried poking around, to see if I could discover something
different about that Customize buffer, but I haven't found
anything.

If you have an idea of something to look for, and you let me
know soon (e.g., before I forget and quit the session at some
point or the session crashes), let me know and I'll take a look.

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Eli Zaretskii]

> Date: Fri, 7 Feb 2014 09:35:18 -0800 (PST)
> From: Drew Adams <drew.adams@oracle.com>
> Cc: 16678@debbugs.gnu.org
> 
> This is very weird.  When I try now, I do not see the bug.
> Last night it was entirely reproducible, from emacs -Q.

Are you trying this in the same binary?  (Sorry for asking the
obvious.)

> If you have an idea of something to look for, and you let me
> know soon (e.g., before I forget and quit the session at some
> point or the session crashes), let me know and I'll take a look.

Sorry, no idea for now.  Anyone?

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Drew Adams]

> Are you trying this in the same binary?  (Sorry for asking the
> obvious.)

Yes, but glad you asked the obvious anyway.

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Lars Ingebrigtsen]

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

> But as I say, for some reason I cannot repro the bug this
> morning.  I will keep an eye out, to see if it happens again.
> But what is weird is that it was reproducible over and over
> last night, but not now.

Are you still seeing this bug?

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

bug#16678: 24.3.50; REGRESSION: text selection is broken in Customize edit fields

[Drew Adams]

> Are you still seeing this bug?

No.  I think this can be closed.  Thx.