YQL-18276: Block singular type implementation

commit_hash:1334e5c0fb5ff26fd40681059409f46cf49ec025

1 files changed, 40 insertions, 0 deletions

diff --git a/yql/essentials/public/udf/arrow/ut/array_builder_ut.cpp b/yql/essentials/public/udf/arrow/ut/array_builder_ut.cpp
index bbb4c134c86..d0851c5e869 100644
--- a/yql/essentials/public/udf/arrow/ut/array_builder_ut.cpp
+++ b/yql/essentials/public/udf/arrow/ut/array_builder_ut.cpp
@@ -220,6 +220,46 @@ Y_UNIT_TEST_SUITE(TArrayBuilderTest) {
         UNIT_ASSERT_VALUES_EQUAL(item2AfterRead.GetStringRefFromValue(), "234");
     }
 
+    Y_UNIT_TEST(TestSingularTypeValueBuilderReader) {
+        TArrayBuilderTestData data;
+        const auto nullType = data.PgmBuilder.NewNullType();
+
+        std::shared_ptr<arrow::ArrayData> arrayData = arrow::NullArray{42}.data();
+        IArrayBuilder::TArrayDataItem arrayDataItem = {.Data = arrayData.get(), .StartOffset = 0};
+        {
+            const auto arrayBuilder = MakeArrayBuilder(NMiniKQL::TTypeInfoHelper(), nullType, *data.ArrowPool, MAX_BLOCK_SIZE, /*pgBuilder=*/nullptr);
+            // Check builder.
+            arrayBuilder->Add(TUnboxedValuePod::Zero());
+            arrayBuilder->Add(TBlockItem::Zero());
+            arrayBuilder->Add(TBlockItem::Zero(), 4);
+            TInputBuffer inputBuffer("Just arbitrary string");
+            arrayBuilder->Add(inputBuffer);
+            arrayBuilder->AddMany(*arrayData, /*popCount=*/3u, /*sparseBitmat=*/nullptr, /*bitmapSize=*/arrayData->length);
+            arrayBuilder->AddMany(&arrayDataItem, /*arrayCount=*/1, /*beginIndex=*/1, /*count=*/3u);
+            std::vector<ui64> indexes = {1, 5, 7, 10};
+            arrayBuilder->AddMany(&arrayDataItem, /*arrayCount=*/1, /*beginIndex=*/indexes.data(), /*count=*/4u);
+            UNIT_ASSERT_VALUES_EQUAL(arrayBuilder->Build(true).array()->length, 1 + 1 + 4 + 1 + 3 + 3 + 4);
+        }
+
+        {
+            // Check reader.
+            const auto blockReader = MakeBlockReader(NMiniKQL::TTypeInfoHelper(), nullType);
+
+            UNIT_ASSERT(blockReader->GetItem(*arrayData, 0));
+            UNIT_ASSERT(blockReader->GetScalarItem(arrow::Scalar(arrow::null())));
+            UNIT_ASSERT_EQUAL(blockReader->GetDataWeight(*arrayData), 0);
+            UNIT_ASSERT_EQUAL(blockReader->GetDataWeight(TBlockItem::Zero()), 0);
+            UNIT_ASSERT_EQUAL(blockReader->GetDefaultValueWeight(), 0);
+            UNIT_ASSERT_EQUAL(blockReader->GetDefaultValueWeight(), 0);
+
+            TOutputBuffer outputBuffer;
+            blockReader->SaveItem(*arrayData, 1, outputBuffer);
+            UNIT_ASSERT(outputBuffer.Finish().empty());
+            blockReader->SaveScalarItem(arrow::Scalar(arrow::null()), outputBuffer);
+            UNIT_ASSERT(outputBuffer.Finish().empty());
+        }
+    }
+
     Y_UNIT_TEST(TestBuilderAllocatedSize) {
         TArrayBuilderTestData data;
         const auto optStringType = data.PgmBuilder.NewDataType(NUdf::EDataSlot::String, true);