kafka: add missing unit tests (#14195)

Signed-off-by: Adam Kotwasinski <adam.kotwasinski@gmail.com>

test/extensions/filters/network/kafka/serialization_test.cc

@@ -101,10 +101,12 @@ TEST(VarUInt32Deserializer, ShouldDeserializeEdgeValues) {
     Buffer::OwnedImpl buffer;
 
     // when
+    const uint32_t expected_size = encoder.computeCompactSize(values[i]);
     const uint32_t written = encoder.encodeCompact(values[i], buffer);
 
     // then
     ASSERT_EQ(written, i + 1);
+    ASSERT_EQ(written, expected_size);
     absl::string_view data = {getRawData(buffer), 1024};
     // All bits in lower bytes need to be set.
     for (auto j = 0; j + 1 < i; ++j) {
@@ -434,6 +436,17 @@ TEST(NullableCompactArrayDeserializer, ShouldConsumeNullArray) {
       NullableCompactArrayDeserializer<Int32Deserializer>>(value);
 }
 
+TEST(NullableCompactArrayDeserializer, ShouldConsumeCorrectAmountOfDataForLargeInput) {
+  std::vector<int32_t> raw;
+  raw.reserve(4096);
+  for (int32_t i = 0; i < 4096; ++i) {
+    raw.push_back(i);
+  }
+  const NullableArray<int32_t> value{raw};
+  serializeCompactThenDeserializeAndCheckEquality<
+      NullableCompactArrayDeserializer<Int32Deserializer>>(value);
+}
+
 // Tagged fields.
 
 TEST(TaggedFieldDeserializer, ShouldConsumeCorrectAmountOfData) {

test/extensions/filters/network/kafka/serialization_utilities.h

@@ -114,12 +114,16 @@ void serializeCompactThenDeserializeAndCheckEqualityInOneGo(AT expected) {
 
   Buffer::OwnedImpl buffer;
   EncodingContext encoder{-1};
+  const uint32_t expected_written_size = encoder.computeCompactSize(expected);
   const uint32_t written = encoder.encodeCompact(expected, buffer);
+  ASSERT_EQ(written, expected_written_size);
   // Insert garbage after serialized payload.
   const uint32_t garbage_size = encoder.encode(Bytes(10000), buffer);
 
+  const char* raw_buffer_ptr =
+      reinterpret_cast<const char*>(buffer.linearize(written + garbage_size));
   // Tell parser that there is more data, it should never consume more than written.
-  const absl::string_view orig_data = {getRawData(buffer), written + garbage_size};
+  const absl::string_view orig_data = {raw_buffer_ptr, written + garbage_size};
   absl::string_view data = orig_data;
 
   // when
@@ -147,11 +151,16 @@ void serializeCompactThenDeserializeAndCheckEqualityWithChunks(AT expected) {
 
   Buffer::OwnedImpl buffer;
   EncodingContext encoder{-1};
+  const uint32_t expected_written_size = encoder.computeCompactSize(expected);
   const uint32_t written = encoder.encodeCompact(expected, buffer);
+  ASSERT_EQ(written, expected_written_size);
   // Insert garbage after serialized payload.
   const uint32_t garbage_size = encoder.encode(Bytes(10000), buffer);
 
-  const absl::string_view orig_data = {getRawData(buffer), written + garbage_size};
+  const char* raw_buffer_ptr =
+      reinterpret_cast<const char*>(buffer.linearize(written + garbage_size));
+  // Tell parser that there is more data, it should never consume more than written.
+  const absl::string_view orig_data = {raw_buffer_ptr, written + garbage_size};
 
   // when
   absl::string_view data = orig_data;