text: // sorted_data_interface_test_spaceused.cpp
  
  /**
   *    Copyright (C) 2014 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.
   */
  
  #include "mongo/db/storage/sorted_data_interface_test_harness.h"
  
  #include <boost/scoped_ptr.hpp>
  
  #include "mongo/db/storage/sorted_data_interface.h"
  #include "mongo/unittest/unittest.h"
  
  namespace mongo {
  
  using boost::scoped_ptr;
  
  // Verify that an empty index takes up no space.
  TEST(SortedDataInterface, GetSpaceUsedBytesEmpty) {
      scoped_ptr<HarnessHelper> harnessHelper(newHarnessHelper());
      scoped_ptr<SortedDataInterface> sorted(harnessHelper->newSortedDataInterface(false));
  
      {
          scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
          ASSERT(sorted->isEmpty(opCtx.get()));
      }
  
      // SERVER-15416 mmapv1 test harness does not use SimpleRecordStoreV1 as its record store
      //              and HeapRecordStoreBtree::dataSize does not have an actual implementation
      // {
      //     scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
      //     ASSERT( sorted->getSpaceUsedBytes( opCtx.get() ) == 0 );
      // }
  }
  
  // Verify that a nonempty index takes up some space.
  TEST(SortedDataInterface, GetSpaceUsedBytesNonEmpty) {
      scoped_ptr<HarnessHelper> harnessHelper(newHarnessHelper());
      scoped_ptr<SortedDataInterface> sorted(harnessHelper->newSortedDataInterface(false));
  
      {
          scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
          ASSERT(sorted->isEmpty(opCtx.get()));
      }
  
      int nToInsert = 10;
      for (int i = 0; i < nToInsert; i++) {
          scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
          {
              WriteUnitOfWork uow(opCtx.get());
              BSONObj key = BSON("" << i);
              RecordId loc(42, i * 2);
              ASSERT_OK(sorted->insert(opCtx.get(), key, loc, true));
              uow.commit();
          }
      }
  
      {
          scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
          ASSERT_EQUALS(nToInsert, sorted->numEntries(opCtx.get()));
      }
  
      // SERVER-15416 mmapv1 test harness does not use SimpleRecordStoreV1 as its record store
      //              and HeapRecordStoreBtree::dataSize does not have an actual implementation
      // long long spaceUsedBytes;
      // {
      //     scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
      //     spaceUsedBytes = sorted->getSpaceUsedBytes( opCtx.get() );
      //     ASSERT( spaceUsedBytes > 0 );
      // }
  
      // {
      //     // getSpaceUsedBytes() returns the same value when called multiple times
      //     // and there were not interleaved write operations.
      //     scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
      //     ASSERT_EQUALS( spaceUsedBytes, sorted->getSpaceUsedBytes( opCtx.get() ) );
      //     ASSERT_EQUALS( spaceUsedBytes, sorted->getSpaceUsedBytes( opCtx.get() ) );
      // }
  }
  
  }  // namespace mongo
  