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diff --git a/src/mongo/util/container_size_helper_test.cpp b/src/mongo/util/container_size_helper_test.cpp
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+++ b/src/mongo/util/container_size_helper_test.cpp
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+/**
+ *    Copyright (C) 2019-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include <vector>
+
+#include "mongo/unittest/unittest.h"
+#include "mongo/util/container_size_helper.h"
+
+namespace {
+
+struct Mock {
+    int size;
+};
+
+TEST(ContainerSizeHelper, TestEstimateObjectSizeInBytes) {
+    std::vector<Mock> vect = {{1}, {2}, {3}, {4}};
+
+    // Sum of 'size' of each element '1 + 2 + 3 + 4'.
+    uint64_t expectedSize = 10;
+
+    // When 'includeComplieTimeSize' is false should return only the sum of sizes calculated by the
+    // 'function'.
+    ASSERT_EQ(mongo::container_size_helper::estimateObjectSizeInBytes(
+                  vect, [](const auto& obj) { return obj.size; }, false),
+              expectedSize);
+
+    // When 'includeShallowSize' is true, should add size of 'Mock' object.
+    ASSERT_EQ(mongo::container_size_helper::estimateObjectSizeInBytes(
+                  vect, [](const auto& obj) { return obj.size; }, true),
+              expectedSize + sizeof(Mock) * vect.capacity());
+}
+
+TEST(ContainerSizeHelper, TestEstimateObjectSizeInBytesWithPointers) {
+    Mock obj1 = {2};
+    Mock obj2 = {1};
+    std::vector<Mock*> vect = {&obj1, &obj1, &obj2};
+
+    // Sum of 'size' of each element '2 + 2 + 1'.
+    uint64_t expectedSize = 5;
+
+    // Reserve extra space for the vector.
+    vect.reserve(10);
+    ASSERT_EQ(static_cast<size_t>(10), vect.capacity());
+
+    // When 'includeShallowSize' is true, should add size of 'Mock*' pointer.
+    ASSERT_EQ(mongo::container_size_helper::estimateObjectSizeInBytes(
+                  vect, [](const auto& obj) { return obj->size; }, true),
+              expectedSize + sizeof(Mock*) * vect.capacity());
+}
+}  // namespace