Add tests for std::pair and std::tuple

types/README.md

@@ -1,6 +1,8 @@
 # Types
 
  * [`fundamental`](fundamental): fundamental column types
+ * [`pair`](pair): `std::pair` with different element types
  * [`string`](string): `std::string` with all `[Split]Index{32,64}` column types
+ * [`tuple`](tuple): `std::tuple` with different element types
  * [`variant`](variant): `std::variant` with `Switch` column type
  * [`vector`](vector): `std::vector` with all `[Split]Index{32,64}` column types

types/pair/README.md

@@ -0,0 +1,15 @@
+# `std::pair`
+
+## Fields
+
+ * `Int32_String`: `std::pair<std::int32_t, std::string>`
+ * `Variant_Vector`: `std::pair<std::variant<std::int32_t, std::string>, std::vector<std::int32_t>>`
+ * `Pair`: `std::pair<std::pair<std::int32_t, std::string>, std::int32_t>`
+ * `VectorPair`: `std::vector<std::pair<std::int32_t, std::string>>`
+
+with the default column types.
+
+## Entries
+
+1. Simple values
+2. Zero / empty values

types/pair/read.C

@@ -0,0 +1,133 @@
+#include <ROOT/REntry.hxx>
+#include <ROOT/RNTupleReader.hxx>
+
+using ROOT::Experimental::REntry;
+using ROOT::Experimental::RNTupleReader;
+
+#include <cstdint>
+#include <fstream>
+#include <ostream>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <variant>
+#include <vector>
+
+using Pair_Int32_String = std::pair<std::int32_t, std::string>;
+using Variant = std::variant<std::int32_t, std::string>;
+using VectorInt32 = std::vector<std::int32_t>;
+
+template <typename T> static void PrintValue(const T &value, std::ostream &os);
+
+template <> void PrintValue(const std::int32_t &value, std::ostream &os) {
+  os << value;
+}
+
+template <> void PrintValue(const std::string &value, std::ostream &os) {
+  os << "\"" << value << "\"";
+}
+
+template <> void PrintValue(const Variant &value, std::ostream &os) {
+  if (value.index() == 0) {
+    PrintValue(std::get<std::int32_t>(value), os);
+  } else if (value.index() == 1) {
+    PrintValue(std::get<std::string>(value), os);
+  }
+}
+
+template <> void PrintValue(const VectorInt32 &value, std::ostream &os) {
+  os << "[";
+  bool first = true;
+  for (auto element : value) {
+    if (first) {
+      first = false;
+    } else {
+      os << ",";
+    }
+    os << "\n        " << element;
+  }
+  if (!value.empty()) {
+    os << "\n      ";
+  }
+  os << "]";
+}
+
+template <> void PrintValue(const Pair_Int32_String &value, std::ostream &os) {
+  os << "[\n";
+  os << "        " << value.first << ",\n";
+  os << "        \"" << value.second << "\"\n";
+  os << "      ]";
+}
+
+template <typename T, typename U>
+static void PrintPairValue(const REntry &entry, std::string_view name,
+                           std::ostream &os, bool last = false) {
+  auto &value = *entry.GetPtr<std::pair<T, U>>(name);
+  os << "    \"" << name << "\": [\n";
+  os << "      ";
+  PrintValue(value.first, os);
+  os << ",\n";
+  os << "      ";
+  PrintValue(value.second, os);
+  os << "\n";
+  os << "    ]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+static void PrintVectorPairValue(const REntry &entry, std::string_view name,
+                                 std::ostream &os, bool last = false) {
+  auto &value = *entry.GetPtr<std::vector<Pair_Int32_String>>(name);
+  os << "    \"" << name << "\": [";
+  bool first = true;
+  for (auto &&element : value) {
+    if (first) {
+      first = false;
+    } else {
+      os << ",";
+    }
+    os << "\n      ";
+    PrintValue(element, os);
+  }
+  if (!value.empty()) {
+    os << "\n    ";
+  }
+  os << "]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+void read(std::string_view input = "types.pair.root",
+          std::string_view output = "types.pair.json") {
+  std::ofstream os(std::string{output});
+  os << "[\n";
+
+  auto reader = RNTupleReader::Open("ntpl", input);
+  auto &entry = reader->GetModel().GetDefaultEntry();
+  bool first = true;
+  for (auto index : *reader) {
+    reader->LoadEntry(index);
+
+    if (first) {
+      first = false;
+    } else {
+      os << ",\n";
+    }
+    os << "  {\n";
+
+    PrintPairValue<std::int32_t, std::string>(entry, "Int32_String", os);
+    PrintPairValue<Variant, VectorInt32>(entry, "Variant_Vector", os);
+    PrintPairValue<Pair_Int32_String, std::int32_t>(entry, "Pair", os);
+    PrintVectorPairValue(entry, "VectorPair", os, /*last=*/true);
+
+    os << "  }";
+    // Newline is intentionally missing, may need to print a comma before the
+    // next entry.
+  }
+  os << "\n";
+  os << "]\n";
+}

types/pair/write.C

@@ -0,0 +1,50 @@
+#include <ROOT/RNTupleModel.hxx>
+#include <ROOT/RNTupleWriteOptions.hxx>
+#include <ROOT/RNTupleWriter.hxx>
+
+using ROOT::Experimental::RNTupleModel;
+using ROOT::Experimental::RNTupleWriteOptions;
+using ROOT::Experimental::RNTupleWriter;
+
+#include <cstdint>
+#include <memory>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <variant>
+#include <vector>
+
+using Pair_Int32_String = std::pair<std::int32_t, std::string>;
+using Variant = std::variant<std::int32_t, std::string>;
+using VectorInt32 = std::vector<std::int32_t>;
+
+void write(std::string_view filename = "types.pair.root") {
+  auto model = RNTupleModel::Create();
+
+  auto Int32_String = model->MakeField<Pair_Int32_String>("Int32_String");
+  auto Variant_Vector =
+      model->MakeField<std::pair<Variant, VectorInt32>>("Variant_Vector");
+  auto Pair =
+      model->MakeField<std::pair<Pair_Int32_String, std::int32_t>>("Pair");
+  auto VectorPair =
+      model->MakeField<std::vector<Pair_Int32_String>>("VectorPair");
+
+  RNTupleWriteOptions options;
+  options.SetCompression(0);
+  auto writer =
+      RNTupleWriter::Recreate(std::move(model), "ntpl", filename, options);
+
+  // First entry: simple values
+  *Int32_String = {1, "abc"};
+  *Variant_Vector = {"def", {2, 3, 4}};
+  *Pair = {{5, "ghi"}, 6};
+  *VectorPair = {{7, "jkl"}, {8, "mno"}};
+  writer->Fill();
+
+  // Second entry: zero / empty values
+  *Int32_String = {0, ""};
+  *Variant_Vector = {0, {}};
+  *Pair = {{0, ""}, 0};
+  *VectorPair = {};
+  writer->Fill();
+}

types/tuple/README.md

@@ -0,0 +1,15 @@
+# `std::tuple`
+
+## Fields
+
+ * `Int32_String_Vector`: `std::tuple<std::int32_t, std::string, std::vector<std::int32_t>>`
+ * `Variant`: `std::tuple<std::variant<std::int32_t, std::string>>`
+ * `Tuple`: `std::tuple<std::tuple<std::int32_t, std::string>>`
+ * `VectorTuple`: `std::vector<std::tuple<std::int32_t, std::string>>`
+
+with the default column types.
+
+## Entries
+
+1. Simple values
+2. Zero / empty values

types/tuple/read.C

@@ -0,0 +1,160 @@
+#include <ROOT/REntry.hxx>
+#include <ROOT/RNTupleReader.hxx>
+
+using ROOT::Experimental::REntry;
+using ROOT::Experimental::RNTupleReader;
+
+#include <cstdint>
+#include <fstream>
+#include <ostream>
+#include <string>
+#include <string_view>
+#include <tuple>
+#include <vector>
+
+using Tuple_Int32_String = std::tuple<std::int32_t, std::string>;
+using VectorInt32 = std::vector<std::int32_t>;
+
+template <typename T> static void PrintValue(const T &value, std::ostream &os);
+
+template <> void PrintValue(const std::int32_t &value, std::ostream &os) {
+  os << value;
+}
+
+template <> void PrintValue(const std::string &value, std::ostream &os) {
+  os << "\"" << value << "\"";
+}
+
+template <> void PrintValue(const VectorInt32 &value, std::ostream &os) {
+  os << "[";
+  bool first = true;
+  for (auto element : value) {
+    if (first) {
+      first = false;
+    } else {
+      os << ",";
+    }
+    os << "\n        " << element;
+  }
+  if (!value.empty()) {
+    os << "\n      ";
+  }
+  os << "]";
+}
+
+template <> void PrintValue(const Tuple_Int32_String &value, std::ostream &os) {
+  os << "[\n";
+  os << "        " << std::get<0>(value) << ",\n";
+  os << "        \"" << std::get<1>(value) << "\"\n";
+  os << "      ]";
+}
+
+static void PrintTupleValue(const REntry &entry, std::string_view name,
+                            std::ostream &os, bool last = false) {
+  auto &value =
+      *entry.GetPtr<std::tuple<std::int32_t, std::string, VectorInt32>>(name);
+  os << "    \"" << name << "\": [\n";
+  os << "      ";
+  PrintValue(std::get<0>(value), os);
+  os << ",\n";
+  os << "      ";
+  PrintValue(std::get<1>(value), os);
+  os << ",\n";
+  os << "      ";
+  PrintValue(std::get<2>(value), os);
+  os << "\n";
+  os << "    ]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+static void PrintVariantValue(const REntry &entry, std::string_view name,
+                              std::ostream &os, bool last = false) {
+  auto &value =
+      *entry.GetPtr<std::tuple<std::variant<std::int32_t, std::string>>>(name);
+  os << "    \"" << name << "\": [\n";
+  os << "      ";
+  auto &variant = std::get<0>(value);
+  if (variant.index() == 0) {
+    PrintValue(std::get<std::int32_t>(variant), os);
+  } else if (variant.index() == 1) {
+    PrintValue(std::get<std::string>(variant), os);
+  }
+  os << "\n";
+  os << "    ]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+static void PrintNestedValue(const REntry &entry, std::string_view name,
+                             std::ostream &os, bool last = false) {
+  auto &value = *entry.GetPtr<std::tuple<Tuple_Int32_String>>(name);
+  os << "    \"" << name << "\": [\n";
+  os << "      ";
+  PrintValue(std::get<0>(value), os);
+  os << "\n";
+  os << "    ]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+static void PrintVectorTupleValue(const REntry &entry, std::string_view name,
+                                  std::ostream &os, bool last = false) {
+  auto &value = *entry.GetPtr<std::vector<Tuple_Int32_String>>(name);
+  os << "    \"" << name << "\": [";
+  bool first = true;
+  for (auto &&element : value) {
+    if (first) {
+      first = false;
+    } else {
+      os << ",";
+    }
+    os << "\n      ";
+    PrintValue(element, os);
+  }
+  if (!value.empty()) {
+    os << "\n    ";
+  }
+  os << "]";
+  if (!last) {
+    os << ",";
+  }
+  os << "\n";
+}
+
+void read(std::string_view input = "types.tuple.root",
+          std::string_view output = "types.tuple.json") {
+  std::ofstream os(std::string{output});
+  os << "[\n";
+
+  auto reader = RNTupleReader::Open("ntpl", input);
+  auto &entry = reader->GetModel().GetDefaultEntry();
+  bool first = true;
+  for (auto index : *reader) {
+    reader->LoadEntry(index);
+
+    if (first) {
+      first = false;
+    } else {
+      os << ",\n";
+    }
+    os << "  {\n";
+
+    PrintTupleValue(entry, "Int32_String_Vector", os);
+    PrintVariantValue(entry, "Variant", os);
+    PrintNestedValue(entry, "Tuple", os);
+    PrintVectorTupleValue(entry, "VectorTuple", os, /*last=*/true);
+
+    os << "  }";
+    // Newline is intentionally missing, may need to print a comma before the
+    // next entry.
+  }
+  os << "\n";
+  os << "]\n";
+}