[PATCH] tarantoolctl: fix cat and play for empty body requests

[Serge Petrenko <sergepetrenko@tarantool.org>]

If space.before_replace returns the old tuple, the operation turns into
no-op, but is still written to WAL as IPROTO_NOP for the sake of
replication. Such a request doesn't have a body, and tarantoolctl failed
to parse such requests in `tarantoolctl cat` and `tarantoolctl play`.
Fix this by skipping such requests, since they have no effect anyway.

Closes #3675
---
https://github.com/tarantool/tarantool/issues/3675
https://github.com/tarantool/tarantool/tree/sp/gh-3675-tarantoolctl-cat-empty-body

 extra/dist/tarantoolctl.in | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/extra/dist/tarantoolctl.in b/extra/dist/tarantoolctl.in
index 3d7ff3ec5..f7b6dd36d 100755
--- a/extra/dist/tarantoolctl.in
+++ b/extra/dist/tarantoolctl.in
@@ -816,11 +816,14 @@ local function cat()
     for id, file in ipairs(positional_arguments) do
         log.error("Processing file '%s'", file)
         for lsn, record in xlog.pairs(file) do
-            local sid = record.BODY.space_id
+            local sid = nil
+            if record.BODY then
+                sid = record.BODY.space_id
+            end
             local rid = record.HEADER.replica_id
-            if (lsn < from) or
+            if (lsn < from) or sid == nil or
                (not spaces and sid and sid < 512 and not show_system) or
-               (spaces and (sid == nil or not find_in_list(sid, spaces))) or
+               (spaces and not find_in_list(sid, spaces)) or
                (replicas and not find_in_list(rid, replicas)) then
                 -- pass this tuple
             elseif lsn >= to then
@@ -857,11 +860,14 @@ local function play()
     for id, file in ipairs(positional_arguments) do
         log.info(("Processing file '%s'"):format(file))
         for lsn, record in xlog.pairs(file) do
-            local sid = record.BODY.space_id
+            local sid = nil
+            if record.BODY then
+                sid = record.BODY.space_id
+            end
             local rid = record.HEADER.replica_id
-            if (lsn < from) or
+            if (lsn < from) or sid == nil or
                (not spaces and sid and sid < 512 and not show_system) or
-               (spaces and (sid == nil or not find_in_list(sid, spaces))) or
+               (spaces and not find_in_list(sid, spaces)) or
                (replicas and not find_in_list(rid, replicas)) then
                 -- pass this tuple
             elseif lsn >= to then
-- 
2.15.2 (Apple Git-101.1)