Merge branch 'jk/log-cherry-pick-duplicate-patches' into maint

When more than one commit with the same patch ID appears on one
side, "git log --cherry-pick A...B" did not exclude them all when a
commit with the same patch ID appears on the other side.  Now it
does.

* jk/log-cherry-pick-duplicate-patches:
  patch-ids: handle duplicate hashmap entries

patch-ids.c

@@ -89,7 +89,7 @@ static int init_patch_id_entry(struct patch_id *patch,
 	return 0;
 }
 
-struct patch_id *has_commit_patch_id(struct commit *commit,
+struct patch_id *patch_id_iter_first(struct commit *commit,
 				     struct patch_ids *ids)
 {
 	struct patch_id patch;
@@ -104,6 +104,18 @@ struct patch_id *has_commit_patch_id(struct commit *commit,
 	return hashmap_get_entry(&ids->patches, &patch, ent, NULL);
 }
 
+struct patch_id *patch_id_iter_next(struct patch_id *cur,
+				    struct patch_ids *ids)
+{
+	return hashmap_get_next_entry(&ids->patches, cur, ent);
+}
+
+int has_commit_patch_id(struct commit *commit,
+			struct patch_ids *ids)
+{
+	return !!patch_id_iter_first(commit, ids);
+}
+
 struct patch_id *add_commit_patch_id(struct commit *commit,
 				     struct patch_ids *ids)
 {

patch-ids.h

@@ -23,7 +23,25 @@ int commit_patch_id(struct commit *commit, struct diff_options *options,
 		    struct object_id *oid, int, int);
 int init_patch_ids(struct repository *, struct patch_ids *);
 int free_patch_ids(struct patch_ids *);
+
+/* Add a patch_id for a single commit to the set. */
 struct patch_id *add_commit_patch_id(struct commit *, struct patch_ids *);
-struct patch_id *has_commit_patch_id(struct commit *, struct patch_ids *);
+
+/* Returns true if the patch-id of "commit" is present in the set. */
+int has_commit_patch_id(struct commit *commit, struct patch_ids *);
+
+/*
+ * Iterate over all commits in the set whose patch id matches that of
+ * "commit", like:
+ *
+ *   struct patch_id *cur;
+ *   for (cur = patch_id_iter_first(commit, ids);
+ *        cur;
+ *        cur = patch_id_iter_next(cur, ids) {
+ *           ... look at cur->commit
+ *   }
+ */
+struct patch_id *patch_id_iter_first(struct commit *commit, struct patch_ids *);
+struct patch_id *patch_id_iter_next(struct patch_id *cur, struct patch_ids *);
 
 #endif /* PATCH_IDS_H */

revision.c

@@ -1241,12 +1241,14 @@ static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
 		/*
 		 * Have we seen the same patch id?
 		 */
-		id = has_commit_patch_id(commit, &ids);
+		id = patch_id_iter_first(commit, &ids);
 		if (!id)
 			continue;
 
 		commit->object.flags |= cherry_flag;
-		id->commit->object.flags |= cherry_flag;
+		do {
+			id->commit->object.flags |= cherry_flag;
+		} while ((id = patch_id_iter_next(id, &ids)));
 	}
 
 	free_patch_ids(&ids);

t/t6007-rev-list-cherry-pick-file.sh

@@ -245,6 +245,18 @@ test_expect_success '--count --left-right' '
 	test_cmp expect actual
 '
 
+test_expect_success '--cherry-pick with duplicates on each side' '
+	git checkout -b dup-orig &&
+	test_commit dup-base &&
+	git revert dup-base &&
+	git cherry-pick dup-base &&
+	git checkout -b dup-side HEAD~3 &&
+	test_tick &&
+	git cherry-pick -3 dup-orig &&
+	git rev-list --cherry-pick dup-orig...dup-side >actual &&
+	test_must_be_empty actual
+'
+
 # Corrupt the object store deliberately to make sure
 # the object is not even checked for its existence.
 remove_loose_object () {