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// PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
/**
 * @file   llinstancetracker_test.cpp
 * @author Nat Goodspeed
 * @date   2009-11-10
 * @brief  Test for llinstancetracker.
 * 
 * $LicenseInfo:firstyear=2009&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

// Precompiled header
#include "linden_common.h"
// associated header
#include "llinstancetracker.h"
// STL headers
#include <string>
#include <vector>
#include <set>
#include <algorithm>                // std::sort()
#include <stdexcept>
// std headers
// external library headers
#include <boost/scoped_ptr.hpp>
// other Linden headers
#include "../test/lltut.h"
#include "wrapllerrs.h"

struct Badness: public std::runtime_error
{
    Badness(const std::string& what): std::runtime_error(what) {}
};

struct Keyed: public LLInstanceTracker<Keyed, std::string>
{
    Keyed(const std::string& name):
        LLInstanceTracker<Keyed, std::string>(name),
        mName(name)
    {}
    std::string mName;
};

struct Unkeyed: public LLInstanceTracker<Unkeyed>
{
    Unkeyed(const std::string& thrw="")
    {
        // LLInstanceTracker should respond appropriately if a subclass
        // constructor throws an exception. Specifically, it should run
        // LLInstanceTracker's destructor and remove itself from the
        // underlying container.
        if (! thrw.empty())
        {
            throw Badness(thrw);
        }
    }
};

/*****************************************************************************
*   TUT
*****************************************************************************/
namespace tut
{
    struct llinstancetracker_data
    {
    };
    typedef test_group<llinstancetracker_data> llinstancetracker_group;
    typedef llinstancetracker_group::object object;
    llinstancetracker_group llinstancetrackergrp("llinstancetracker");

    template<> template<>
    void object::test<1>()
    {
        ensure_equals(Keyed::instanceCount(), 0);
        {
            Keyed one("one");
            ensure_equals(Keyed::instanceCount(), 1);
            Keyed* found = Keyed::getInstance("one");
            ensure("couldn't find stack Keyed", found);
            ensure_equals("found wrong Keyed instance", found, &one);
            {
                boost::scoped_ptr<Keyed> two(new Keyed("two"));
                ensure_equals(Keyed::instanceCount(), 2);
                Keyed* found = Keyed::getInstance("two");
                ensure("couldn't find heap Keyed", found);
                ensure_equals("found wrong Keyed instance", found, two.get());
            }
            ensure_equals(Keyed::instanceCount(), 1);
        }
        Keyed* found = Keyed::getInstance("one");
        ensure("Keyed key lives too long", ! found);
        ensure_equals(Keyed::instanceCount(), 0);
    }

    template<> template<>
    void object::test<2>()
    {
        ensure_equals(Unkeyed::instanceCount(), 0);
        Unkeyed* dangling = NULL;
        {
            Unkeyed one;
            ensure_equals(Unkeyed::instanceCount(), 1);
            Unkeyed* found = Unkeyed::getInstance(&one);
            ensure_equals(found, &one);
            {
                boost::scoped_ptr<Unkeyed> two(new Unkeyed);
                ensure_equals(Unkeyed::instanceCount(), 2);
                Unkeyed* found = Unkeyed::getInstance(two.get());
                ensure_equals(found, two.get());
            }
            ensure_equals(Unkeyed::instanceCount(), 1);
            // store an unwise pointer to a temp Unkeyed instance
            dangling = &one;
        } // make that instance vanish
        // check the now-invalid pointer to the destroyed instance
        ensure("getInstance(T*) failed to track destruction", ! Unkeyed::getInstance(dangling));
        ensure_equals(Unkeyed::instanceCount(), 0);
    }

    template<> template<>
    void object::test<3>()
    {
        Keyed one("one"), two("two"), three("three");
        // We don't want to rely on the underlying container delivering keys
        // in any particular order. That allows us the flexibility to
        // reimplement LLInstanceTracker using, say, a hash map instead of a
        // std::map. We DO insist that every key appear exactly once.
        typedef std::vector<std::string> StringVector;
        StringVector keys(Keyed::beginKeys(), Keyed::endKeys());
        std::sort(keys.begin(), keys.end());
        StringVector::const_iterator ki(keys.begin());
        ensure_equals(*ki++, "one");
        ensure_equals(*ki++, "three");
        ensure_equals(*ki++, "two");
        // Use ensure() here because ensure_equals would want to display
        // mismatched values, and frankly that wouldn't help much.
        ensure("didn't reach end", ki == keys.end());

        // Use a somewhat different approach to order independence with
        // beginInstances(): explicitly capture the instances we know in a
        // set, and delete them as we iterate through.
        typedef std::set<Keyed*> InstanceSet;
        InstanceSet instances;
        instances.insert(&one);
        instances.insert(&two);
        instances.insert(&three);
        for (Keyed::instance_iter ii(Keyed::beginInstances()), iend(Keyed::endInstances());
             ii != iend; ++ii)
        {
            Keyed& ref = *ii;
            ensure_equals("spurious instance", instances.erase(&ref), 1);
        }
        ensure_equals("unreported instance", instances.size(), 0);
    }

    template<> template<>
    void object::test<4>()
    {
        Unkeyed one, two, three;
        typedef std::set<Unkeyed*> KeySet;
    
        KeySet instances;
        instances.insert(&one);
        instances.insert(&two);
        instances.insert(&three);

		for (Unkeyed::instance_iter ii(Unkeyed::beginInstances()), iend(Unkeyed::endInstances()); ii != iend; ++ii)
		{
			Unkeyed& ref = *ii;
			ensure_equals("spurious instance", instances.erase(&ref), 1);
		}

        ensure_equals("unreported instance", instances.size(), 0);
    }

    template<> template<>
    void object::test<5>()
    {
        set_test_name("exception in subclass ctor");
        typedef std::set<Unkeyed*> InstanceSet;
        InstanceSet existing;
        // We can't use the iterator-range InstanceSet constructor because
        // beginInstances() returns an iterator that dereferences to an
        // Unkeyed&, not an Unkeyed*.
        for (Unkeyed::instance_iter uki(Unkeyed::beginInstances()),
                                    ukend(Unkeyed::endInstances());
             uki != ukend; ++uki)
        {
            existing.insert(&*uki);
        }
        try
        {
            // We don't expect the assignment to take place because we expect
            // Unkeyed to respond to the non-empty string param by throwing.
            // We know the LLInstanceTracker base-class constructor will have
            // run before Unkeyed's constructor, therefore the new instance
            // will have added itself to the underlying set. The whole
            // question is, when Unkeyed's constructor throws, will
            // LLInstanceTracker's destructor remove it from the set? I
            // realize we're testing the C++ implementation more than
            // Unkeyed's implementation, but this seems an important point to
            // nail down.
            new Unkeyed("throw");
        }
        catch (const Badness&)
        {
        }
        // Ensure that every member of the new, updated set of Unkeyed
        // instances was also present in the original set. If that's not true,
        // it's because our new Unkeyed ended up in the updated set despite
        // its constructor exception.
        for (Unkeyed::instance_iter uki(Unkeyed::beginInstances()),
                                    ukend(Unkeyed::endInstances());
             uki != ukend; ++uki)
        {
            ensure("failed to remove instance", existing.find(&*uki) != existing.end());
        }
    }
} // namespace tut
