Steps to reproduce:
Launch `emacs -Q`, paste these four lines on a buffer
aaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaa'aaaaaaaaaaaaaaaaaaa'aaaaaaaaaa
aaaaaaaaa’aaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaa’aaaaaaaaaaaaaaaaaaa’aaaaaaaaaa
nnnnnnnnn'nnnnnnnnnnnnnnnnnnnnnnnnnnnn nnnn'nnnnnnnnnnnnnnnnnnn'nnnnnnnnnn
nnnnnnnnn’nnnnnnnnnnnnnnnnnnnnnnnnnnnn nnnn’nnnnnnnnnnnnnnnnnnn’nnnnnnnnnn
Search for the first one with char folding enabled. In my system Emacs
doesn’t match the second line. It matches after I hit ‘C-M-d’ to
delete the last character from the search query.
If you search with char folding enabled for the third line then it
does match the fourth, even though the third and the fourth lines are
just copies of the first two with the a’s replaced by n’s.
All the best,
Andrea
In GNU Emacs 27.2 (build 1, x86_64-redhat-linux-gnu, GTK+ Version 3.24.30, cairo version 1.17.4)
of 2021-08-07 built on
buildvm-x86-29.iad2.fedoraproject.orgWindowing system distributor 'The X.Org Foundation', version 11.0.12101003
System Description: Fedora 34 (Workstation Edition)
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Making completion list... [2 times]
Configured using:
'configure --build=x86_64-redhat-linux-gnu
--host=x86_64-redhat-linux-gnu --program-prefix=
--disable-dependency-tracking --prefix=/usr --exec-prefix=/usr
--bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc
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--with-cairo --with-json build_alias=x86_64-redhat-linux-gnu
host_alias=x86_64-redhat-linux-gnu CC=gcc 'CFLAGS=-DMAIL_USE_LOCKF -O2
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LDFLAGS=-Wl,-z,relro
PKG_CONFIG_PATH=:/usr/lib64/pkgconfig:/usr/share/pkgconfig'
Configured features:
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INOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF
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Important settings:
value of $LANG: en_GB.UTF-8
value of $XMODIFIERS: @im=ibus
locale-coding-system: utf-8-unix
Major mode: Lisp Interaction
Minor modes in effect:
tooltip-mode: t
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eldoc-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
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blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
line-number-mode: t
transient-mark-mode: t
Load-path shadows:
None found.
Features:
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Memory information:
((conses 16 45893 6606)
(symbols 48 6007 1)
(strings 32 15796 1378)
(string-bytes 1 518486)
(vectors 16 10238)
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