ref-filter: allow merged and no-merged filters

Enable ref-filter to process multiple merged and no-merged filters, and
extend functionality to git branch, git tag and git for-each-ref. This
provides an easy way to check for branches that are "graduation
candidates:"

$ git branch --no-merged master --merged next

If passed more than one merged (or more than one no-merged) filter, refs
must be reachable from any one of the merged commits, and reachable from
none of the no-merged commits.

Signed-off-by: Aaron Lipman <alipman88@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 35 insertions, 29 deletions

diff --git a/ref-filter.c b/ref-filter.c
index 110bcd741a..785785a757 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -2167,9 +2167,9 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 	 * obtain the commit using the 'oid' available and discard all
 	 * non-commits early. The actual filtering is done later.
 	 */
-	if (filter->merge_commit || filter->with_commit || filter->no_commit || filter->verbose) {
-		commit = lookup_commit_reference_gently(the_repository, oid,
-							1);
+	if (filter->reachable_from || filter->unreachable_from ||
+	    filter->with_commit || filter->no_commit || filter->verbose) {
+		commit = lookup_commit_reference_gently(the_repository, oid, 1);
 		if (!commit)
 			return 0;
 		/* We perform the filtering for the '--contains' option... */
@@ -2231,13 +2231,20 @@ void ref_array_clear(struct ref_array *array)
 	}
 }
 
-static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
+static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata, int reachable)
 {
 	struct rev_info revs;
 	int i, old_nr;
-	struct ref_filter *filter = ref_cbdata->filter;
 	struct ref_array *array = ref_cbdata->array;
 	struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
+	struct commit_list *rl;
+
+	struct commit_list *check_reachable_list = reachable ?
+		ref_cbdata->filter->reachable_from :
+		ref_cbdata->filter->unreachable_from;
+
+	if (!check_reachable_list)
+		return;
 
 	repo_init_revisions(the_repository, &revs, NULL);
 
@@ -2247,8 +2254,11 @@ static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
 		to_clear[i] = item->commit;
 	}
 
-	filter->merge_commit->object.flags |= UNINTERESTING;
-	add_pending_object(&revs, &filter->merge_commit->object, "");
+	for (rl = check_reachable_list; rl; rl = rl->next) {
+		struct commit *merge_commit = rl->item;
+		merge_commit->object.flags |= UNINTERESTING;
+		add_pending_object(&revs, &merge_commit->object, "");
+	}
 
 	revs.limited = 1;
 	if (prepare_revision_walk(&revs))
@@ -2263,14 +2273,19 @@ static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
 
 		int is_merged = !!(commit->object.flags & UNINTERESTING);
 
-		if (is_merged == (filter->merge == REF_FILTER_MERGED_INCLUDE))
+		if (is_merged == reachable)
 			array->items[array->nr++] = array->items[i];
 		else
 			free_array_item(item);
 	}
 
 	clear_commit_marks_many(old_nr, to_clear, ALL_REV_FLAGS);
-	clear_commit_marks(filter->merge_commit, ALL_REV_FLAGS);
+
+	while (check_reachable_list) {
+		struct commit *merge_commit = pop_commit(&check_reachable_list);
+		clear_commit_marks(merge_commit, ALL_REV_FLAGS);
+	}
+
 	free(to_clear);
 }
 
@@ -2322,8 +2337,8 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 	clear_contains_cache(&ref_cbdata.no_contains_cache);
 
 	/*  Filters that need revision walking */
-	if (filter->merge_commit)
-		do_merge_filter(&ref_cbdata);
+	do_merge_filter(&ref_cbdata, DO_MERGE_FILTER_REACHABLE);
+	do_merge_filter(&ref_cbdata, DO_MERGE_FILTER_UNREACHABLE);
 
 	return ret;
 }
@@ -2541,31 +2556,22 @@ int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
 {
 	struct ref_filter *rf = opt->value;
 	struct object_id oid;
-	int no_merged = starts_with(opt->long_name, "no");
+	struct commit *merge_commit;
 
 	BUG_ON_OPT_NEG(unset);
 
-	if (rf->merge) {
-		if (no_merged) {
-			return error(_("option `%s' is incompatible with --merged"),
-				     opt->long_name);
-		} else {
-			return error(_("option `%s' is incompatible with --no-merged"),
-				     opt->long_name);
-		}
-	}
-
-	rf->merge = no_merged
-		? REF_FILTER_MERGED_OMIT
-		: REF_FILTER_MERGED_INCLUDE;
-
 	if (get_oid(arg, &oid))
 		die(_("malformed object name %s"), arg);
 
-	rf->merge_commit = lookup_commit_reference_gently(the_repository,
-							  &oid, 0);
-	if (!rf->merge_commit)
+	merge_commit = lookup_commit_reference_gently(the_repository, &oid, 0);
+
+	if (!merge_commit)
 		return error(_("option `%s' must point to a commit"), opt->long_name);
 
+	if (starts_with(opt->long_name, "no"))
+		commit_list_insert(merge_commit, &rf->unreachable_from);
+	else
+		commit_list_insert(merge_commit, &rf->reachable_from);
+
 	return 0;
 }