Re: [PATCH 2/2] pathspec: don't error out on all-exclusionary pathspec patterns

[Junio C Hamano <gitster@pobox.com>]

Linus Torvalds <torvalds@linux-foundation.org> writes:

> @@ -546,10 +546,16 @@ void parse_pathspec(struct pathspec *pathspec,
>  		pathspec->magic |= item[i].magic;
>  	}
>  
> -	if (nr_exclude == n)
> -		die(_("There is nothing to exclude from by :(exclude) patterns.\n"
> -		      "Perhaps you forgot to add either ':/' or '.' ?"));
> -
> +	/*
> +	 * If everything is an exclude pattern, add one positive pattern
> +	 * that matches everyting. We allocated an extra one for this.
> +	 */
> +	if (nr_exclude == n) {
> +		if (!(flags & PATHSPEC_PREFER_CWD))
> +			prefixlen = 0;
> +		init_pathspec_item(item + n, 0, prefix, prefixlen, "");
> +		pathspec->nr++;
> +	}
>  
>  	if (pathspec->magic & PATHSPEC_MAXDEPTH) {
>  		if (flags & PATHSPEC_KEEP_ORDER)

Thanks.  Even though the current code does not refer to the original
prefixlen after the added hunk, I'd prefer not to destroy it to
avoid future troubles, so I'll queue with a bit of tweak there,
perhaps like the attached.

Also this has an obvious fallout to the tests, whose (minimum) fix
is rather trivial.

Thanks.

 pathspec.c                  | 7 +++----
 t/t6132-pathspec-exclude.sh | 6 ++++--
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/pathspec.c b/pathspec.c
index d8f78088c8..b961f00c8c 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -522,7 +522,7 @@ void parse_pathspec(struct pathspec *pathspec,
 	}
 
 	pathspec->nr = n;
-	ALLOC_ARRAY(pathspec->items, n+1);
+	ALLOC_ARRAY(pathspec->items, n + 1);
 	item = pathspec->items;
 	prefixlen = prefix ? strlen(prefix) : 0;
 
@@ -551,9 +551,8 @@ void parse_pathspec(struct pathspec *pathspec,
 	 * that matches everyting. We allocated an extra one for this.
 	 */
 	if (nr_exclude == n) {
-		if (!(flags & PATHSPEC_PREFER_CWD))
-			prefixlen = 0;
-		init_pathspec_item(item + n, 0, prefix, prefixlen, "");
+		int plen = (!(flags & PATHSPEC_PREFER_CWD)) ? 0 : prefixlen;
+		init_pathspec_item(item + n, 0, prefix, plen, "");
 		pathspec->nr++;
 	}
 
diff --git a/t/t6132-pathspec-exclude.sh b/t/t6132-pathspec-exclude.sh
index d51595cf6b..9dd5cde5fc 100755
--- a/t/t6132-pathspec-exclude.sh
+++ b/t/t6132-pathspec-exclude.sh
@@ -25,8 +25,10 @@ EOF
 	test_cmp expect actual
 '
 
-test_expect_success 'exclude only should error out' '
-	test_must_fail git log --oneline --format=%s -- ":(exclude)sub"
+test_expect_success 'exclude only no longer errors out' '
+	git log --oneline --format=%s -- . ":(exclude)sub" >expect &&
+	git log --oneline --format=%s -- ":(exclude)sub" >actual &&
+	test_cmp expect actual
 '
 
 test_expect_success 't_e_i() exclude sub' '