bug#58992: 28.2; "lax space matching" no longer works

[Vincent Lefevre <vincent@vinc17.net>]

On 2022-11-03 18:21:57 +0100, Vincent Lefevre wrote:
> On 2022-11-03 19:04:31 +0200, Eli Zaretskii wrote:
> > > From: Vincent Lefevre <vincent@vinc17.net>
> > > Date: Thu, 03 Nov 2022 17:53:16 +0100
> > > 
> > > The Emacs manual says:
> > > 
> > > 15.9 Lax Matching During Searching
> > > ==================================
> > > [...]
> > >    By default, search commands perform “lax space matching”: each space,
> > > or sequence of spaces, matches any sequence of one or more whitespace
> > > characters in the text.  (Incremental regexp search has a separate
> > > default; see *note Regexp Search::.)  Hence, ‘foo bar’ matches
> > > ‘foo bar’, ‘foo  bar’, ‘foo   bar’, and so on (but not ‘foobar’).  More
> > > [...]
> > > 
> > > This is working with GNU Emacs 27, but not with GNU Emacs 28.2
> > > (tested under Debian/unstable).
> > 
> > If it works for you by default in Emacs 27, then you either didn't
> > test with "emacs -Q" there or your Emacs 27 is customized wrt the
> > upstream.
> 
> I tested with "emacs -Q", and I've just tested again. I confirm the
> behavior I could see: a newline character is matched. That's Debian's
> package emacs-gtk 1:27.1+1-3.1+b1. So perhaps Debian has changed the
> default (but no changes were announced in Debian for Emacs 28, whose
> behavior is different).

In the officiel lisp/isearch.el file from the Debian/stable package
(i.e. *not* in the debian subdirectory):

(defcustom search-whitespace-regexp (purecopy "\\s-+")

So it doesn't seem to be a Debian customization.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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