blame: silently ignore invalid ignore file objects

Since 610e2b9 (blame: validate and peel the object names on the
ignore list, 2020-09-24) git blame reports checks if objects specified
with --ignore-rev and in files loaded with --ignore-revs-file and config
option blame.ignoreRevsFile are actual objects and dies if they aren't.
The intent is to report typos to the user.

This also breaks the ability to use a single ignore file for multiple
repositories.  Typos are presumably less likely in files than on the
command line, so alerting is less useful here.  Restore that feature by
skipping non-commits without dying.

Reported-by: Jean-Yves Avenard <jyavenard@mozilla.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Reviewed-by: Barret Rhoden <brho@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: rscharfe

oidset.c

@@ -72,9 +72,10 @@ void oidset_parse_file_carefully(struct oidset *set, const char *path,
 		if (!sb.len)
 			continue;
 
-		if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0' ||
-		    (fn && fn(&oid, cbdata)))
+		if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0')
 			die("invalid object name: %s", sb.buf);
+		if (fn && fn(&oid, cbdata))
+			continue;
 		oidset_insert(set, &oid);
 	}
 	if (ferror(fp))

t/t8013-blame-ignore-revs.sh

@@ -39,10 +39,10 @@ test_expect_success 'validate --ignore-rev' '
 	test_must_fail git blame --ignore-rev X^{tree} file
 '
 
-# Ensure bogus --ignore-revs-file requests are caught
+# Ensure bogus --ignore-revs-file requests are silently accepted
 test_expect_success 'validate --ignore-revs-file' '
 	git rev-parse X^{tree} >ignore_x &&
-	test_must_fail git blame --ignore-revs-file ignore_x file
+	git blame --ignore-revs-file ignore_x file
 '
 
 for I in X XT