Regression test for SC-53334. (#5254)

This demonstrates an error running the MIN aggregate function on the
`STRING_ASCII` datatype whose cell val num is 1.

Expected behavior: this should behave the same way as using the `UINT8`
data type, which has the same physical 1-byte data width. Or, if this
expectation is against tiledb philosophy, at least there should be a
clear error about the operation being unsupported.

The added regression test demonstrates that we do not have the same
behavior for these two types. Running MIN on `STRING_ASCII` throws an
exception.



---
TYPE: NO_HISTORY
DESC: Regression test for SC-53334.

---------

Co-authored-by: KiterLuc <[email protected]>

Author: rroelke

test/regression/CMakeLists.txt

@@ -51,6 +51,7 @@ if (TILEDB_CPP_API)
   list(APPEND SOURCES targets/sc-35424.cc)
   list(APPEND SOURCES targets/sc-36372.cc)
   list(APPEND SOURCES targets/sc-38300.cc)
+  list(APPEND SOURCES targets/sc-53334.cc)
 endif()
 
 add_executable(tiledb_regression

test/regression/targets/sc-53334.cc

@@ -0,0 +1,197 @@
+/**
+ * @file   sc-53334.cc
+ *
+ * @section LICENSE
+ *
+ * The MIT License
+ *
+ * @copyright Copyright (c) 2024 TileDB, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @section DESCRIPTION
+ *
+ * When run, this program will create a simple 2D sparse array, write some data
+ * to it in global order, and read the data back with aggregates.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <tiledb/tiledb.h>
+#include <tiledb/tiledb>
+#include <tiledb/tiledb_experimental>
+#include <vector>
+
+#include <catch2/catch_template_test_macros.hpp>
+
+using namespace tiledb;
+
+typedef char min_type;
+
+template <tiledb_datatype_t attribute_type>
+struct AttributeTraits;
+
+template <>
+struct AttributeTraits<TILEDB_UINT8> {
+  typedef uint8_t value_type;
+};
+
+template <>
+struct AttributeTraits<TILEDB_STRING_ASCII> {
+  typedef char value_type;
+};
+
+template <tiledb_datatype_t attribute_datatype>
+struct MyArray {
+  using AttributeValueType =
+      typename AttributeTraits<attribute_datatype>::value_type;
+
+  static void create_array(Context& ctx, const char* array_name) {
+    // The array will be 4x4 with dimensions "rows" and "cols", with domain
+    // [1,4].
+    auto rows = Dimension::create<int32_t>(ctx, "rows", {{1, 4}}, 4);
+    auto cols = Dimension::create<int32_t>(ctx, "columns", {{1, 4}}, 4);
+
+    // Create domain
+    Domain domain(ctx);
+    domain.add_dimension(rows);
+    domain.add_dimension(cols);
+
+    // Create a single attribute "a" so each (i,j) cell can store a character
+    Attribute a(ctx, "a", attribute_datatype);
+
+    // Create array schema
+    ArraySchema schema(ctx, TILEDB_SPARSE);
+    schema.set_domain(domain);
+    schema.set_cell_order(TILEDB_ROW_MAJOR);
+    schema.set_tile_order(TILEDB_ROW_MAJOR);
+    schema.add_attribute(a);
+
+    // Create array
+    Array::create(array_name, schema);
+  }
+
+  static void write_array(Context& ctx, const char* array_name) {
+    // Open array for writing
+    Array array(ctx, array_name, TILEDB_WRITE);
+
+    // Data
+    std::vector<int32_t> rows = {
+        1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4};
+    std::vector<int32_t> cols = {
+        1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4};
+    std::vector<AttributeValueType> atts = {
+        'a',
+        'b',
+        'c',
+        'd',
+        'e',
+        'f',
+        'g',
+        'h',
+        'i',
+        'j',
+        'k',
+        'l',
+        'm',
+        'n',
+        'o',
+        'p'};
+
+    Query query(ctx, array);
+    query.set_data_buffer("rows", rows)
+        .set_data_buffer("columns", cols)
+        .set_data_buffer("a", atts);
+
+    query.submit();
+    array.close();
+  }
+
+  static AttributeValueType query_min(Context& ctx, const char* array_name) {
+    // note, use C API because the CPP API doesn't seem to have Min yet
+    Array array(ctx, array_name, TILEDB_READ);
+
+    Query query(ctx, array);
+    query.set_layout(TILEDB_UNORDERED);
+
+    QueryChannel default_channel =
+        QueryExperimental::get_default_channel(query);
+    ChannelOperation operation =
+        QueryExperimental::create_unary_aggregate<MinOperator>(query, "a");
+    default_channel.apply_aggregate("Min", operation);
+
+    std::vector<AttributeValueType> min(1);
+    query.set_data_buffer("Min", min);
+
+    query.submit();
+    query.finalize();
+
+    return min[0];
+  }
+};
+
+bool array_exists(Context& ctx, const char* uri) {
+  auto object = tiledb::Object::object(ctx, uri);
+  return (object.type() == tiledb::Object::Type::Array);
+}
+
+TEST_CASE("SC-53334 min single value UINT8 works", "[bug][sc-53334]") {
+  using MyArray = MyArray<TILEDB_UINT8>;
+
+  Context ctx;
+  std::string uri("sc-53334-uint8");
+
+  if (!array_exists(ctx, uri.c_str())) {
+    MyArray::create_array(ctx, uri.c_str());
+    MyArray::write_array(ctx, uri.c_str());
+  }
+
+  const uint8_t min = MyArray::query_min(ctx, uri.c_str());
+  REQUIRE(min == 'a');
+}
+
+TEST_CASE(
+    "SC-53334 min single value STRING_ASCII does not work",
+    "[regression][bug][sc-53334][!shouldfail]") {
+  using MyArray = MyArray<TILEDB_STRING_ASCII>;
+
+  Context ctx;
+  std::string uri("sc-53334-string-ascii");
+
+  if (!array_exists(ctx, uri.c_str())) {
+    MyArray::create_array(ctx, uri.c_str());
+    MyArray::write_array(ctx, uri.c_str());
+  }
+
+  /*
+   * This throws an exception instead of returning the correct result "a".
+   *
+   * "OutputBufferValidator: Aggregate fixed size buffer should be for one
+   * element" This happens because the Min/Max ops are specialized to do
+   * std::string as their internal result buffer, but we are looking for a
+   * single `char` result.
+   *
+   * When the bug is fixed, delete `CHECK_THROWS` and `if (false)`.
+   */
+  CHECK_NOTHROW(MyArray::query_min(ctx, uri.c_str()));
+  if (false) {
+    const char min = MyArray::query_min(ctx, uri.c_str());
+    REQUIRE(min == 'a');
+  }
+}