/*
 * This file is part of the GROMACS molecular simulation package.
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 * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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/*! \internal \file
 * \brief Tests for the EnergyDriftTacker class
 *
 * \author berk Hess <hess@kth.se>
 * \ingroup module_mdlib
 */
#include "gmxpre.h"

#include "gromacs/mdlib/energydrifttracker.h"

#include <gtest/gtest.h>

#include "testutils/testasserts.h"

namespace gmx
{

namespace
{

TEST(EnergyDriftTracker, emptyWorks)
{
    EnergyDriftTracker tracker(1);

    EXPECT_EQ(tracker.timeInterval(), 0);
    EXPECT_EQ(tracker.energyDrift(), 0);
}

TEST(EnergyDriftTracker, onePointWorks)
{
    EnergyDriftTracker tracker(1);

    tracker.addPoint(1.5, -3.5_real);
    EXPECT_EQ(tracker.timeInterval(), 0);
    EXPECT_EQ(tracker.energyDrift(), 0);
}

TEST(EnergyDriftTracker, manyPointsWorks)
{
    EnergyDriftTracker tracker(10);

    tracker.addPoint(1.5, 2.5_real);
    tracker.addPoint(3.5, 4.0_real);
    tracker.addPoint(5.5, -5.5_real);
    EXPECT_FLOAT_EQ(tracker.timeInterval(), 4.0_real);
    EXPECT_FLOAT_EQ(tracker.energyDrift(), -0.2_real);
}

} // namespace

} // namespace gmx
