v2.25.0-rc0 test failure on cygwin

I noticed on Friday, while testing the v2.25.0-rc0 build, that test t6137 failed on cygwin:

  $ tail test-out-2-50-rc0 
  Test Summary Report
  -------------------
  t6137-pathspec-wildcards-literal.sh              (Wstat: 256 (exited 1) Tests: 25 Failed: 11)
    Failed tests:  2, 7, 9, 11, 14-15, 17, 19, 21, 23, 25
    Non-zero exit status: 1
  Files=1023, Tests=30946, 21783 wallclock secs (19.08 usr 42.17 sys + 4031.65 cusr 12965.78 csys = 17058.68 CPU)
  Result: FAIL
  make[1]: *** [Makefile:78: prove] Error 1
  make[1]: Leaving directory '/home/ramsay/git/t'
  make: *** [Makefile:3286: test] Error 2
  $ 

A quick squint at the failing tests made it clear that the failure was caused by the cygwin build treating a quoted glob character sequence (e.g. '\*') as a directory separator char followed by a glob character.

To show this, I quickly hacked up a patch which causes the test to pass:

  diff --git a/abspath.h b/abspath.h
  index 4653080d5e..a5e30a3033 100644
  --- a/abspath.h
  +++ b/abspath.h
  @@ -27,7 +27,7 @@ char *prefix_filename_except_for_dash(const char *prefix, const char *path);
   
   static inline int is_absolute_path(const char *path)
   {
  -	return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
  +	return /*is_dir_sep(path[0])*/ path[0] == '/' || has_dos_drive_prefix(path);
   }
   
   /**
  diff --git a/path.c b/path.c
  index 3b598b2847..f000b9ffff 100644
  --- a/path.c
  +++ b/path.c
  @@ -1223,13 +1223,15 @@ int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
   	end = src + offset_1st_component(src);
   	while (src < end) {
   		char c = *src++;
  +#ifdef DUMMY
   		if (is_dir_sep(c))
   			c = '/';
  +#endif
   		*dst++ = c;
   	}
   	dst0 = dst;
   
  -	while (is_dir_sep(*src))
  +	while (/*is_dir_sep(*src)*/ *src == '/')
   		src++;
   
   	for (;;) {
  @@ -1247,10 +1249,10 @@ int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
   			if (!src[1]) {
   				/* (1) */
   				src++;
  -			} else if (is_dir_sep(src[1])) {
  +			} else if (/*is_dir_sep(src[1])*/ src[1] == '/') {
   				/* (2) */
   				src += 2;
  -				while (is_dir_sep(*src))
  +				while (/*is_dir_sep(*src)*/ *src == '/')
   					src++;
   				continue;
   			} else if (src[1] == '.') {
  @@ -1258,10 +1260,10 @@ int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
   					/* (3) */
   					src += 2;
   					goto up_one;
  -				} else if (is_dir_sep(src[2])) {
  +				} else if (/*is_dir_sep(src[2])*/ src[2] == '/') {
   					/* (4) */
   					src += 3;
  -					while (is_dir_sep(*src))
  +					while (/*is_dir_sep(*src)*/ *src == '/')
   						src++;
   					goto up_one;
   				}
  @@ -1269,11 +1271,11 @@ int normalize_path_copy_len(char *dst, const char *src, int *prefix_len)
   		}
   
   		/* copy up to the next '/', and eat all '/' */
  -		while ((c = *src++) != '\0' && !is_dir_sep(c))
  +		while ((c = *src++) != '\0' && !(/*is_dir_sep(c)*/ c == '/'))
   			*dst++ = c;
  -		if (is_dir_sep(c)) {
  +		if (/*is_dir_sep(c)*/ c == '/') {
   			*dst++ = '/';
  -			while (is_dir_sep(c))
  +			while (/*is_dir_sep(c)*/ c == '/')
   				c = *src++;
   			src--;
   		} else if (!c)

In other words, in 'is_absolute_path()' and 'normalize_path_copy_len()', then just disable the '\' character as a path separator! ;)

This was just to demonstrate the problem, not a serious patch, of course!

I was away for the weekend and was expecting to see a patch to fix this on Gfw when I got back, but to my surprise there has been no mention of it on the mailing list (having now waded through the backlog!).

To be clear, I can not imagine that this test passes on Gfw. However, this should have been failing the windows CI for ages, so ... perhaps I don't have a sufficiently vivid imagination. :)

Anyway, the patch below 'fixes' the issue on cygwin.

Thanks.

ATB, Ramsay Jones

---- >8 ----
From: Ramsay Jones <ramsay@ramsayjones.plus.com>
Date: Mon, 2 Jun 2025 22:51:33 +0100
Subject: [PATCH] t6137: disable 'quoted glob' pathspecs on cygwin

The backslash in a 'quoted glob' character is treated as a directory separator character on cygwin, which causes all such tests to fail. Skip all such tests on cygwin using the !CYGWIN prerequisite. While here, fix a few test titles as well.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
---
 t/t6137-pathspec-wildcards-literal.sh | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)