[ntuple] test size check in RVec reading

Author: jblomer

tree/ntuple/test/CMakeLists.txt

@@ -92,6 +92,7 @@ ROOT_ADD_GTEST(ntuple_extended ntuple_extended.cxx LIBRARIES ROOTNTuple MathCore
 if(NOT MSVC OR win_broken_tests)
   ROOT_ADD_GTEST(ntuple_largefile1 ntuple_largefile1.cxx LIBRARIES ROOTNTuple MathCore)
   ROOT_ADD_GTEST(ntuple_largefile2 ntuple_largefile2.cxx LIBRARIES ROOTNTuple MathCore)
+  ROOT_ADD_GTEST(ntuple_largevector ntuple_largevector.cxx LIBRARIES ROOTNTuple)
 endif()
 ROOT_ADD_GTEST(ntuple_randomaccess ntuple_randomaccess.cxx LIBRARIES ROOTNTuple MathCore)
 

tree/ntuple/test/ntuple_largevector.cxx

@@ -0,0 +1,46 @@
+#include "ntuple_test.hxx"
+
+#include <limits>
+
+TEST(RNTuple, LargeVector)
+{
+   FileRaii fileGuard("test_ntuple_large_vector.root");
+
+   // write out a vector too large for RVec
+   {
+      auto m = RNTupleModel::Create();
+      auto vec = m->MakeField<std::vector<int8_t>>("v");
+      auto writer = RNTupleWriter::Recreate(std::move(m), "r", fileGuard.GetPath());
+      vec->push_back(1);
+      writer->Fill();
+      vec->resize(std::numeric_limits<std::int32_t>::max());
+      writer->Fill();
+      vec->push_back(2);
+      writer->Fill();
+      vec->clear();
+      writer->Fill();
+   }
+
+   // read them back as the other type
+   ROOT::RNTupleReadOptions options;
+   options.SetClusterCache(ROOT::RNTupleReadOptions::EClusterCache::kOff);
+   auto reader = RNTupleReader::Open("r", fileGuard.GetPath(), options);
+   ASSERT_EQ(4u, reader->GetNEntries());
+
+   auto viewRVec = reader->GetView<ROOT::RVec<int8_t>>("v");
+   EXPECT_EQ(1u, viewRVec(0).size());
+   EXPECT_EQ(1, viewRVec(0).at(0));
+   const auto &v1 = viewRVec(1);
+   EXPECT_EQ(std::numeric_limits<std::int32_t>::max(), v1.size());
+   EXPECT_EQ(1, v1.at(0));
+   EXPECT_EQ(0, v1.at(1000));
+   EXPECT_THROW(viewRVec(2), ROOT::RException);
+   EXPECT_TRUE(viewRVec(3).empty());
+
+   auto viewVector = reader->GetView<std::vector<int8_t>>("v");
+   const auto &v3 = viewVector(2);
+   EXPECT_EQ(static_cast<std::size_t>(std::numeric_limits<std::int32_t>::max()) + 1, v3.size());
+   EXPECT_EQ(1, v3.at(0));
+   EXPECT_EQ(0, v3.at(1000));
+   EXPECT_EQ(2, v3.at(std::numeric_limits<std::int32_t>::max()));
+}