Commit: patch 9.2.0245: xxd: color output detection is broken

[Christian Brabandt]

patch 9.2.0245: xxd: color output detection is broken

Commit: https://github.com/vim/vim/commit/1578ea9d97aefcdd6e89774d274ad0f440c34383
Author: Hirohito Higashi <h.eas...@gmail.com>
Date: Wed Mar 25 19:38:51 2026 +0000

patch 9.2.0245: xxd: color output detection is broken

Problem: xxd: color output detection is broken
(Juergen Weigert)
Solution: Fix the issues (Hirohito Higashi)

- Disable auto color when output goes to a file (two-argument form)
- Check TERM variable: disable color when unset, empty or "dumb"
- Add color_forced flag to preserve -R always behavior
- Add tests for the new behavior

fixes: #19790
closes: #19813

Co-Authored-By: Claude Opus 4.6 (1M context) <nor...@anthropic.com>
Signed-off-by: Hirohito Higashi <h.eas...@gmail.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/testdir/test_xxd.vim b/src/testdir/test_xxd.vim
index d460315f7..472dfd4ee 100644
--- a/src/testdir/test_xxd.vim
+++ b/src/testdir/test_xxd.vim
@@ -758,4 +758,68 @@ func Test_xxd_null_dereference()
bw!
endfunc

+func Test_xxd_color_outfile_no_color()
+ CheckUnix
+
+ " When output goes to a file (two-argument form), auto color should be
+ " disabled and produce the same result as redirect to file.
+ let input = 'Xxd_color_input'
+ let outfile = 'Xxd_color_outfile'
+ let outredir = 'Xxd_color_outredir'
+
+ call writefile([repeat('A', 100)], input)
+
+ " Two-argument form: xxd infile outfile
+ silent exe '!' . s:xxd_cmd . ' ' . input . ' ' . outfile
+
+ " Redirect form: xxd infile > outfile
+ silent exe '!' . s:xxd_cmd . ' ' . input . ' > ' . outredir
+
+ call assert_equal(readfile(outredir), readfile(outfile))
+
+ call delete(input)
+ call delete(outfile)
+ call delete(outredir)
+endfunc
+
+func Test_xxd_color_term_dumb()
+ CheckUnix
+
+ " When TERM is 'dumb', auto color should be disabled.
+ let input = 'Xxd_term_input'
+ let outfile = 'Xxd_term_outfile'
+
+ call writefile([repeat('A', 100)], input)
+
+ silent exe '!' . 'TERM=dumb ' . s:xxd_cmd . ' ' . input . ' > ' . outfile
+ let result = readfile(outfile)
+ " Output should not contain escape sequences
+ for line in result
+ call assert_equal(-1, stridx(line, " "), 'Unexpected color escape in: ' . line)
+ endfor
+
+ call delete(input)
+ call delete(outfile)
+endfunc
+
+func Test_xxd_color_term_unset()
+ CheckUnix
+
+ " When TERM is not set, auto color should be disabled.
+ let input = 'Xxd_unset_input'
+ let outfile = 'Xxd_unset_outfile'
+
+ call writefile([repeat('A', 100)], input)
+
+ silent exe '!' . 'env -u TERM ' . s:xxd_cmd . ' ' . input . ' > ' . outfile
+ let result = readfile(outfile)
+ " Output should not contain escape sequences
+ for line in result
+ call assert_equal(-1, stridx(line, " "), 'Unexpected color escape in: ' . line)
+ endfor
+
+ call delete(input)
+ call delete(outfile)
+endfunc
+
" vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index d6021159d..9edef9b90 100644
--- a/src/version.c
+++ b/src/version.c
@@ -734,6 +734,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 245,
/**/
244,
/**/
diff --git a/src/xxd/xxd.c b/src/xxd/xxd.c
index 1dc0f383d..535f0add3 100644
--- a/src/xxd/xxd.c
+++ b/src/xxd/xxd.c
@@ -73,6 +73,7 @@
* 24.08.2025 avoid NULL dereference with autoskip colorless
* 26.11.2025 update indent in exit_with_usage()
* 19.03.2026 Add -t option to end output with terminating null
+ * 25.03.2026 Fix color output issues
*
* (c) 1990-1998 by Juergen Weigert (jnwe...@gmail.com)
*
@@ -153,7 +154,7 @@ extern void perror __P((char *));
# endif
#endif

-char version[] = "xxd 2026-03-19 by Juergen Weigert et al.";
+char version[] = "xxd 2026-03-25 by Juergen Weigert et al.";
#ifdef WIN32
char osver[] = " (Win32)";
#else
@@ -723,7 +724,16 @@ enable_color(void)
mode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
return (int)SetConsoleMode(out, mode);
#elif defined(UNIX)
- return isatty(STDOUT_FILENO);
+ char *term;
+
+ if (!isatty(STDOUT_FILENO))
+ return 0;
+
+ term = getenv("TERM");
+ if (term == NULL || *term == '
+ return 0;
+
+ return 1;
#else
return 0;
#endif
@@ -748,6 +758,7 @@ main(int argc, char *argv[])
char *varname = NULL;
int addrlen = 9;
int color = 0;
+ int color_forced = 0; /* set when -R always is used */
char *no_color;
char cur_color = 0;

@@ -920,6 +931,7 @@ main(int argc, char *argv[])
{
(void)enable_color();
color = 1;
+ color_forced = 1;
}
else if (!STRNCMP(pw, "never", 5))
color = 0;
@@ -1018,6 +1030,10 @@ main(int argc, char *argv[])
return 3;
}
rewind(fpo);
+
+ /* Disable auto color when writing to a file. */
+ if (!color_forced)
+ color = 0;
}

if (revert)