custom allocator test

tdigest/test/CMakeLists.txt

@@ -38,6 +38,7 @@ add_test(
 target_sources(tdigest_test
   PRIVATE
     tdigest_test.cpp
+    tdigest_custom_allocator_test.cpp
 )
 
 if (GENERATE)

tdigest/test/tdigest_custom_allocator_test.cpp

@@ -0,0 +1,43 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, 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.
+ */
+
+#include <catch2/catch.hpp>
+
+#include "tdigest.hpp"
+#include "test_allocator.hpp"
+
+namespace datasketches {
+
+using alloc_d = test_allocator<double>;
+using tdigest_d = tdigest<double, alloc_d>;
+
+TEST_CASE("tdigest custom allocator", "[tdigest]") {
+  test_allocator_total_bytes = 0;
+  test_allocator_net_allocations = 0;
+  {
+    tdigest_d td(100, alloc_d(0));
+    for (int i = 0; i < 10000; ++i) td.update(static_cast<double>(i));
+    REQUIRE(test_allocator_total_bytes != 0);
+    REQUIRE(test_allocator_net_allocations != 0);
+  }
+  REQUIRE(test_allocator_total_bytes == 0);
+  REQUIRE(test_allocator_net_allocations == 0);
+}
+
+} /* namespace datasketches */