[PATCH v2 6/6] last-modified: keep per-path Bloom filters for wildcard pathspecs

The last-modified builtin expands the pathspec to a set of literal paths
and builds a Bloom key for each. During the walk it looks those keys up
in the commit's filter to decide whether the commit is worth diffing.
These lookups need `bloom_filter_settings` for the key hashing.

prepare_revision_walk() runs prepare_to_use_bloom_filter() to build the
pathspec key vectors. For a pathspec that cannot be turned into a Bloom
key, such as a top-level wildcard like "*.c", that function gives up and
clears `bloom_filter_settings`.

Restore `bloom_filter_settings` after prepare_revision_walk() so the
per-path check keeps working for wildcard pathspecs.

Signed-off-by: Toon Claes <[email protected]>
---
 builtin/last-modified.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/builtin/last-modified.c b/builtin/last-modified.c
index 5678731a04..35d9dccd9b 100644
--- a/builtin/last-modified.c
+++ b/builtin/last-modified.c
@@ -369,6 +369,14 @@ static int last_modified_run(struct last_modified *lm)
 
 	prepare_revision_walk(&lm->rev);
 
+	/*
+	 * prepare_revision_walk() clears bloom_filter_settings for pathspecs
+	 * without a Bloom key. Restore it so the per-path check keeps working.
+	 */
+	if (!lm->rev.bloom_filter_settings)
+		lm->rev.bloom_filter_settings =
+			get_bloom_filter_settings(lm->rev.repo);
+
 	max_count = lm->rev.max_count;
 
 	init_active_paths_for_commit(&lm->active_paths);

-- 
2.55.0.679.g6767b8d81c