From d5c1c01f67f06067f06e12f205851d1c03cdbf15 Mon Sep 17 00:00:00 2001
From: Andrey Saranchin <Andrey22102001@gmail.com>
Date: Tue, 15 Oct 2024 21:23:58 +0300
Subject: [PATCH] buffer: allow to read zero bytes

Decoder can try to read zero bytes sometimes. For example, when
it received an empty string. Let's simply handle this case in buffer
instead of assertion.

By the way, `ClientTest.cpp` was failing with Tarantool 3.2 because of
this problem: when connector tries to call a non-existing function
(`*** TEST CASE call wrong function ***`), Tarantool sends an empty
string in response.
---
 src/Buffer/Buffer.hpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Buffer/Buffer.hpp b/src/Buffer/Buffer.hpp
index 647b121ba..459af3335 100644
--- a/src/Buffer/Buffer.hpp
+++ b/src/Buffer/Buffer.hpp
@@ -1238,7 +1238,8 @@ template <bool LIGHT>
 void
 Buffer<N, allocator>::iterator_common<LIGHT>::read(RData data)
 {
-	assert(data.size > 0);
+	if (data.size == 0)
+		return;
 	/*
 	 * The same implementation as in ::set() method buf vice versa:
 	 * buffer and data sources are swapped.