revision: fix --no-walk path filtering regression

Since dd4bc01c0a (revision: use priority queue for non-limited
streaming walks, 2026-05-27), "git rev-list --no-walk <commit>
-- <path>" ignores the path arguments and outputs all commits
regardless of whether they touch the given paths.

That commit introduced a REV_WALK_NO_WALK enum value to separate
--no-walk from the streaming walk in get_revision_1(). The new
case skips process_parents(), which is correct for not enqueuing
parents, but also skips try_to_simplify_commit() which
process_parents() calls to evaluate whether each commit touches
the given paths.

Add a call to try_to_simplify_commit() for the
REV_WALK_NO_WALK case, folding it into the existing
REV_WALK_REFLOG case which already does the same.

Add tests for --no-walk path filtering to t6017. The
"single commit, match" test is defensive and passes without
the fix, while the other two fail without it.

Reported-by: Peter Colberg <pcolberg@redhat.com>
Signed-off-by: Kristofer Karlsson <krka@spotify.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/revision.c b/revision.c
index 4bb3b16..57e0e23 100644
--- a/revision.c
+++ b/revision.c
@@ -4387,6 +4387,7 @@ static struct commit *get_revision_1(struct rev_info *revs)
 
 		switch (mode) {
 		case REV_WALK_REFLOG:
+		case REV_WALK_NO_WALK:
 			try_to_simplify_commit(revs, commit);
 			break;
 		case REV_WALK_TOPO:
@@ -4400,7 +4401,6 @@ static struct commit *get_revision_1(struct rev_info *revs)
 					    oid_to_hex(&commit->object.oid));
 			}
 			break;
-		case REV_WALK_NO_WALK:
 		case REV_WALK_LIMITED:
 			break;
 		}
diff --git a/t/t6017-rev-list-stdin.sh b/t/t6017-rev-list-stdin.sh
index 4821b90..32284f1 100755
--- a/t/t6017-rev-list-stdin.sh
+++ b/t/t6017-rev-list-stdin.sh
@@ -148,4 +148,22 @@
 	test_cmp expect actual
 '
 
+test_expect_success '--no-walk filters by path (single commit, match)' '
+	git rev-parse side-1 >expect &&
+	git rev-list --no-walk side-1 -- file-1 >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--no-walk filters by path (single commit, no match)' '
+	git rev-list --no-walk side-2 -- file-1 >actual &&
+	test_must_be_empty actual
+'
+
+test_expect_success '--no-walk with pathspec exclusion' '
+	git rev-parse side-3 side-2 >expect &&
+	git rev-parse side-1 side-2 side-3 >input &&
+	git rev-list --stdin --no-walk -- ":!file-1" <input >actual &&
+	test_cmp expect actual
+'
+
 test_done