Commit: patch 9.1.1700: Multiline ignorecase specific pattern does not match with 'ignorecase'

[Christian Brabandt]

patch 9.1.1700: Multiline ignorecase specific pattern does not match with 'ignorecase'

Commit: https://github.com/vim/vim/commit/bf82e58a702900c70638e8047039fdf5f12f749f
Author: Christian Brabandt <c...@256bit.org>
Date: Wed Aug 27 18:14:27 2025 +0200

patch 9.1.1700: Multiline ignorecase specific pattern does not match with 'ignorecase'

Problem: a pattern that involves a backref on a different line does not
match when 'ignorecase' is set (QiWei, after v9.1.0645)
Solution: Use MB_STRNICMP when ignorecase is set, fix tests to close
swapfiles

related: #14756
fixes: #17470
closes: #18104

Signed-off-by: author
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/regexp.c b/src/regexp.c
index 669b123a3..dc63cccfc 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -1569,6 +1569,7 @@ reg_nextline(void)
* Returns RA_FAIL, RA_NOMATCH or RA_MATCH.
* If "bytelen" is not NULL, it is set to the byte length of the match in the
* last line.
+ * Optional: ignore case if rex.reg_ic is set.
*/
static int
match_with_backref(
@@ -1613,7 +1614,9 @@ match_with_backref(
else
len = (int)reg_getline_len(clnum) - ccol;

- if (cstrncmp(p + ccol, rex.input, &len) != 0)
+ // Use case-insensitive compare if rex.reg_ic is set
+ if ((!rex.reg_ic && cstrncmp(p + ccol, rex.input, &len) != 0)
+ || (rex.reg_ic && MB_STRNICMP(p + ccol, rex.input, len) != 0))
return RA_NOMATCH; // doesn't match
if (bytelen != NULL)
*bytelen += len;
diff --git a/src/testdir/test_regexp_utf8.vim b/src/testdir/test_regexp_utf8.vim
index a4353f1b4..6eb6bf6fa 100644
--- a/src/testdir/test_regexp_utf8.vim
+++ b/src/testdir/test_regexp_utf8.vim
@@ -453,7 +453,7 @@ func Run_regexp_multibyte_magic()
@w
call assert_equal('k œ̄ṣ́m̥̄ᾱ̆́', getline(18))

- close!
+ bw!
endfunc

func Test_regexp_multibyte_magic()
@@ -471,7 +471,7 @@ func Test_split_multibyte_to_bytes()
call setline(1, 'l äö üᾱ̆́')
s/ \?/ /g
call assert_equal(' l ä ö ü ᾱ̆́', getline(1))
- close!
+ bw!
endfunc

" Test for matchstr() with multibyte characters
@@ -481,7 +481,7 @@ func Test_matchstr_multibyte()
call assert_equal('בג', matchstr("אבגד", "..", 0, 2))
call assert_equal('א', matchstr("אבגד", ".", 0, 0))
call assert_equal('ג', matchstr("אבגד", ".", 4, -1))
- close!
+ bw!
endfunc

" Test for 7.4.636
@@ -492,7 +492,7 @@ func Test_search_with_end_offset()
exe "normal /(/e+\<CR>"
normal n"ayn
call assert_equal("a
cat(", @a)
- close!
+ bw!
endfunc

" Check that "^" matches even when the line starts with a combining char
@@ -614,7 +614,23 @@ func Test_search_multibyte_match_ascii()
call assert_equal(['s', 'ss', 'ſſ', 'ſ'], ic_match3, "Ignorecase Collection Regex-engine: " .. &re)
call assert_equal(['ſſ','ſ'], noic_match3, "No-Ignorecase Collection Regex-engine: " .. &re)
endfor
+ set re&vim
bw!
endfunc

+func Test_replace_multibyte_match_in_multi_lines()
+ new
+ let text = ['ab 1c', 'ab 1c', 'def', '是否 a', '是否 a', 'ghi', '是否a', '是否a', '是否 1', '是否 1']
+ let expected = ['', 'def', '', 'ghi', '', '']
+ for i in range(0, 2)
+ exe "set ignorecase re="..i
+ :%d _
+ call setline(1, text)
+ :%s/\(.\+\)
//g
+ call assert_equal(expected, getline(1, '$'))
+ endfor
+ bw!
+ set ignorecase&vim re&vim
+endfun
+
" vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index 0bcd55691..48c5c1c3e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -724,6 +724,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1700,
/**/
1699,
/**/