(fix): Fix Flakiness in Writer Unit Test

dwio/nimble/encodings/tests/EncodingSelectionTests.cpp

@@ -989,7 +989,7 @@ TEST(EncodingSelectionTests, TestNullable) {
   // test getRawDataSize
   auto size =
       facebook::nimble::test::TestUtils::getRawDataSize(*pool, serialized);
-  auto expectedSize = 15 + 6; // 15 bytes for string data, 6 bytes for nulls
+  auto expectedSize = 15 + 10; // 15 bytes for string data, 10 bytes for nulls
   ASSERT_EQ(size, expectedSize);
 
   LOG(INFO) << "Final size: " << serialized.size();

dwio/nimble/encodings/tests/TestUtils.cpp

@@ -38,11 +38,8 @@ uint64_t TestUtils::getRawDataSize(
   if (encodingType == EncodingType::Nullable) {
     auto pos = encodingStr.data() + kPrefixSize;
     auto nonNullsSize = encoding::readUint32(pos);
-    auto nonNullsCount = encoding::peek<uint32_t>(pos + kRowCountOffset);
-    // We do not count the bits indicating non-null, therefore we only
-    // include the size of the null bits and the non-null values.
-    return getRawDataSize(memoryPool, {pos, nonNullsSize}) +
-        (rowCount - nonNullsCount);
+    // Sum of the  nulls count and size of the non-null child encoding.
+    return getRawDataSize(memoryPool, {pos, nonNullsSize}) + rowCount;
   } else {
     if (dataType != DataType::String) {
       auto typeSize = nimble::detail::dataTypeSize(dataType);

dwio/nimble/tablet/CMakeLists.txt

@@ -29,7 +29,7 @@ target_include_directories(
 )
 add_dependencies(nimble_footer_fb nimble_footer_schema_fb)
 
-add_library(nimble_tablet_common Compression.cpp, MetadataBuffer.cpp)
+add_library(nimble_tablet_common Compression.cpp MetadataBuffer.cpp)
 target_link_libraries(nimble_tablet_common nimble_footer_fb Folly::folly)
 
 add_library(nimble_tablet_reader TabletReader.cpp)

dwio/nimble/tablet/tests/CMakeLists.txt

@@ -11,8 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-add_executable(
-  nimble_tabletReader_tests TabletTest.cpp MetadataBufferTest.cpp)
+add_executable(nimble_tabletReader_tests TabletTest.cpp MetadataBufferTest.cpp)
 
 add_test(nimble_tabletReader_tests nimble_tabletReader_tests)
 

dwio/nimble/velox/tests/VeloxWriterTests.cpp

@@ -2239,12 +2239,15 @@ TEST_F(VeloxWriterTests, fuzzComplex) {
     }
 
     const auto iterations = 20;
+    // provide sufficient buffer between min and max chunk size thresholds
+    constexpr uint64_t chunkThresholdBuffer = sizeof(int64_t) + sizeof(bool);
     for (auto i = 0; i < iterations; ++i) {
       writerOptions.minStreamChunkRawSize =
           std::uniform_int_distribution<uint64_t>(10, 4096)(rng);
       writerOptions.maxStreamChunkRawSize =
           std::uniform_int_distribution<uint64_t>(
-              writerOptions.minStreamChunkRawSize, 8192)(rng);
+              writerOptions.minStreamChunkRawSize + chunkThresholdBuffer,
+              8192)(rng);
       const auto batchSize =
           std::uniform_int_distribution<uint32_t>(10, 400)(rng);
       const auto batchCount = 5;