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diff --git a/src/mongo/bson/bsonobj_comparator.h b/src/mongo/bson/bsonobj_comparator.h
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+/**
+ *    Copyright (C) 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    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
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    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 GNU Affero General 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.
+ */
+
+#pragma once
+
+#include "mongo/base/string_data_comparator_interface.h"
+#include "mongo/bson/bsonobj_comparator_interface.h"
+
+namespace mongo {
+
+/**
+ * A BSONObj comparator that supports:
+ * - Comparing with respect to an ordering spec such as {a: 1, b: -1}.
+ * - Ignoring field names during comparison.
+ * - Passing a custom string comparator.
+ */
+class BSONObjComparator final : public BSONObj::ComparatorInterface {
+public:
+    enum class FieldNamesMode {
+        kConsider,
+        kIgnore,
+    };
+
+    /**
+     * Constructs a BSONObj comparator which will use the 'ordering' pattern for comparisons.
+     *
+     * Will not consider BSON field names in comparisons if 'fieldNamesMode' is kIgnore.
+     *
+     * If 'stringComparator' is null, uses default binary string comparison. Otherwise,
+     * 'stringComparator' is used for all string comparisons.
+     */
+    BSONObjComparator(BSONObj ordering,
+                      FieldNamesMode fieldNamesMode,
+                      const StringData::ComparatorInterface* stringComparator)
+        : _ordering(std::move(ordering)),
+          _fieldNamesMode(fieldNamesMode),
+          _stringComparator(stringComparator) {}
+
+    int compare(const BSONObj& lhs, const BSONObj& rhs) const final {
+        const bool considerFieldName = (_fieldNamesMode == FieldNamesMode::kConsider);
+        return lhs.woCompare(rhs, _ordering, considerFieldName, _stringComparator);
+    }
+
+private:
+    BSONObj _ordering;
+    FieldNamesMode _fieldNamesMode;
+    const StringData::ComparatorInterface* _stringComparator;
+};
+
+}  // namespace mongo