[Tarantool-patches] [PATCH] vinyl: fix comment to vy_read_iterator_cmp_stmt()

[Nikita Pettik <korablev@tarantool.org>]

vy_read_iterator_cmp_stmt() uses tuple_compare_with_key() under the hood
which follows next convention:
(a) it returns 0 if key_fields of tuple equal to given key;
(b) < 0 if key_fields less than given key;
(c) > 0 otherwise.
However, comment to vy_read_iterator_cmp_stmt() says that:
(a) it returns -1 if first statement precedes second one;
(b) 0 if they at the same position;
(c) +1 if first statement supersedes second one.
so, since there's no "normalization" of return code from
tuple_compare_with_key() it would be correct to say that
vy_read_iterator_cmp_stmt() returns:
(a) it returns arbitrary integer value < 0 if first statement precedes
second one;
(b) 0 if they at the same position;
(c) arbitrary integer value > 0 if first statement supersedes second one.
---
 src/box/vy_read_iterator.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/box/vy_read_iterator.c b/src/box/vy_read_iterator.c
index 9ea07709e..dcc9a0873 100644
--- a/src/box/vy_read_iterator.c
+++ b/src/box/vy_read_iterator.c
@@ -168,9 +168,9 @@ vy_read_iterator_range_is_done(struct vy_read_iterator *itr,
  * Compare two tuples from the read iterator perspective.
  *
  * Returns:
- *  -1 if statement @a precedes statement @b in the iterator output
- *   0 if statements @a and @b are at the same position
- *   1 if statement @a supersedes statement @b
+ *  < 0 if statement @a precedes statement @b in the iterator output
+ * == 0 if statements @a and @b are at the same position
+ *  > 0 if statement @a supersedes statement @b
  *
  * NULL denotes the statement following the last one.
  */
-- 
2.17.1