test_pns_basics.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright The KiCad Developers, see AUTHORS.txt for contributors.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */
 
#include <qa_utils/wx_utils/unit_test_utils.h>
#include <settings/settings_manager.h>
#include <optional>
 
#include <pcbnew/board.h>
#include <pcbnew/pad.h>
#include <pcbnew/pcb_track.h>
 
#include <geometry/shape_circle.h>
#include <router/pns_item.h>
#include <router/pns_kicad_iface.h>
#include <router/pns_node.h>
#include <router/pns_router.h>
#include <router/pns_segment.h>
#include <router/pns_solid.h>
#include <router/pns_via.h>
 
static bool isCopper( const PNS::ITEM* aItem )
{
    if( !aItem )
        return false;
 
    BOARD_ITEM* parent = aItem->Parent();
 
    if( parent && parent->Type() == PCB_PAD_T )
    {
        PAD* pad = static_cast<PAD*>( parent );
 
        if( pad->IsAperturePad() || pad->IsNPTHWithNoCopper() )
            return false;
    }
 
    return true;
}
 
 
static bool isHole( const PNS::ITEM* aItem )
{
    if( !aItem )
        return false;
 
    return aItem->OfKind( PNS::ITEM::HOLE_T );
}
 
 
static bool isEdge( const PNS::ITEM* aItem )
{
    if( !aItem )
        return false;
 
    const BOARD_ITEM *parent = aItem->BoardItem();
 
    return parent && ( parent->IsOnLayer( Edge_Cuts ) || parent->IsOnLayer( Margin ) );
}
 
 
class MOCK_RULE_RESOLVER : public PNS::RULE_RESOLVER
{
public:
    MOCK_RULE_RESOLVER() : m_clearanceEpsilon( 10 )
    {
    }
 
    virtual ~MOCK_RULE_RESOLVER() {}
 
    virtual int Clearance( const PNS::ITEM* aA, const PNS::ITEM* aB,
                           bool aUseClearanceEpsilon = true ) override
    {
        PNS::CONSTRAINT constraint;
        int             rv = 0;
        PNS_LAYER_RANGE     layers;
 
        if( !aB )
            layers = aA->Layers();
        else if( isEdge( aA ) )
            layers = aB->Layers();
        else if( isEdge( aB ) )
            layers = aA->Layers();
        else
            layers = aA->Layers().Intersection( aB->Layers() );
 
        // Normalize layer range (no -1 magic numbers)
        layers = layers.Intersection( PNS_LAYER_RANGE( PCBNEW_LAYER_ID_START, PCB_LAYER_ID_COUNT - 1 ) );
 
        for( int layer = layers.Start(); layer <= layers.End(); ++layer )
        {
            if( isHole( aA ) && isHole( aB) )
            {
                if( QueryConstraint( PNS::CONSTRAINT_TYPE::CT_HOLE_TO_HOLE, aA, aB, layer, &constraint ) )
                {
                    if( constraint.m_Value.Min() > rv )
                        rv = constraint.m_Value.Min();
                }
            }
            else if( isHole( aA ) || isHole( aB ) )
            {
                if( QueryConstraint( PNS::CONSTRAINT_TYPE::CT_HOLE_CLEARANCE, aA, aB, layer, &constraint ) )
                {
                    if( constraint.m_Value.Min() > rv )
                        rv = constraint.m_Value.Min();
                }
            }
            else if( isCopper( aA ) && ( !aB || isCopper( aB ) ) )
            {
                if( QueryConstraint( PNS::CONSTRAINT_TYPE::CT_CLEARANCE, aA, aB, layer, &constraint ) )
                {
                    if( constraint.m_Value.Min() > rv )
                        rv = constraint.m_Value.Min();
                }
            }
            else if( isEdge( aA ) || ( aB && isEdge( aB ) ) )
            {
                if( QueryConstraint( PNS::CONSTRAINT_TYPE::CT_EDGE_CLEARANCE, aA, aB, layer, &constraint ) )
                {
                    if( constraint.m_Value.Min() > rv )
                        rv = constraint.m_Value.Min();
                }
            }
        }
 
        return rv;
    }
 
    virtual PNS::NET_HANDLE DpCoupledNet( PNS::NET_HANDLE aNet ) override { return nullptr; }
    virtual int DpNetPolarity( PNS::NET_HANDLE aNet ) override { return -1; }
 
    virtual bool DpNetPair( const PNS::ITEM* aItem, PNS::NET_HANDLE& aNetP,
                            PNS::NET_HANDLE& aNetN ) override
    {
        return false;
    }
 
    virtual int NetCode( PNS::NET_HANDLE aNet ) override
    {
        return -1;
    }
 
    virtual wxString NetName( PNS::NET_HANDLE aNet ) override
    {
        return wxEmptyString;
    }
 
    virtual bool QueryConstraint( PNS::CONSTRAINT_TYPE aType, const PNS::ITEM* aItemA,
                                  const PNS::ITEM* aItemB, int aLayer,
                                  PNS::CONSTRAINT* aConstraint ) override
    {
        ITEM_KEY key;
 
        key.a = aItemA;
        key.b = aItemB;
        key.type = aType;
 
        auto it = m_ruleMap.find( key );
 
        if( it == m_ruleMap.end() )
        {
            int cl;
            switch( aType )
            {
            case PNS::CONSTRAINT_TYPE::CT_CLEARANCE:      cl = m_defaultClearance;   break;
            case PNS::CONSTRAINT_TYPE::CT_HOLE_TO_HOLE:   cl = m_defaultHole2Hole;   break;
            case PNS::CONSTRAINT_TYPE::CT_HOLE_CLEARANCE: cl = m_defaultHole2Copper; break;
            default: return false;
            }
 
            //printf("GetDef %s %s %d cl %d\n", aItemA->KindStr().c_str(), aItemB->KindStr().c_str(), aType, cl );
 
            aConstraint->m_Type = aType;
            aConstraint->m_Value.SetMin( cl );
 
            return true;
        }
        else
        {
            *aConstraint = it->second;
        }
 
        return true;
    }
 
    int ClearanceEpsilon() const override { return m_clearanceEpsilon; }
 
    struct ITEM_KEY
    {
        const PNS::ITEM*     a = nullptr;
        const PNS::ITEM*     b = nullptr;
        PNS::CONSTRAINT_TYPE type;
 
        bool operator==( const ITEM_KEY& other ) const
        {
            return a == other.a && b == other.b && type == other.type;
        }
 
        bool operator<( const ITEM_KEY& other ) const
        {
            if( a < other.a )
            {
                return true;
            }
            else if ( a == other.a )
            {
                if( b < other.b )
                    return true;
                else if ( b == other.b )
                    return type < other.type;
            }
 
            return false;
        }
    };
 
    bool IsInNetTie( const PNS::ITEM* aA ) override { return false; }
 
    bool IsNetTieExclusion( const PNS::ITEM* aItem, const VECTOR2I& aCollisionPos,
                            const PNS::ITEM* aCollidingItem ) override
    {
        return false;
    }
 
    bool IsDrilledHole( const PNS::ITEM* aItem ) override { return false; }
 
    bool IsNonPlatedSlot( const PNS::ITEM* aItem ) override { return false; }
 
    bool IsKeepout( const PNS::ITEM* aObstacle, const PNS::ITEM* aItem, bool* aEnforce ) override
    {
        return false;
    }
 
    void AddMockRule( PNS::CONSTRAINT_TYPE aType, const PNS::ITEM* aItemA, const PNS::ITEM* aItemB,
                      PNS::CONSTRAINT& aConstraint )
    {
        ITEM_KEY key;
 
        key.a = aItemA;
        key.b = aItemB;
        key.type = aType;
 
        m_ruleMap[key] = aConstraint;
    }
 
    int m_defaultClearance = 200000;
    int m_defaultHole2Hole = 220000;
    int m_defaultHole2Copper = 210000;
 
private:
    std::map<ITEM_KEY, PNS::CONSTRAINT> m_ruleMap;
    int                                 m_clearanceEpsilon;
};
 
struct PNS_TEST_FIXTURE;
 
class MOCK_PNS_KICAD_IFACE : public PNS_KICAD_IFACE_BASE
{
public:
    MOCK_PNS_KICAD_IFACE( PNS_TEST_FIXTURE *aFixture ) :
        m_testFixture( aFixture )
    {}
 
    ~MOCK_PNS_KICAD_IFACE() override {}
 
    void HideItem( PNS::ITEM* aItem ) override {};
    void DisplayItem( const PNS::ITEM* aItem, int aClearance, bool aEdit = false,
                      int aFlags = 0 ) override {};
    PNS::RULE_RESOLVER* GetRuleResolver() override;
 
    bool TestInheritTrackWidth( PNS::ITEM* aItem, int* aInheritedWidth,
                                const VECTOR2I& aStartPosition = VECTOR2I() )
    {
        return inheritTrackWidth( aItem, aInheritedWidth, aStartPosition );
    }
 
private:
    PNS_TEST_FIXTURE* m_testFixture;
};
 
 
struct PNS_TEST_FIXTURE
{
    PNS_TEST_FIXTURE()
    {
        m_router = new PNS::ROUTER;
        m_iface = new MOCK_PNS_KICAD_IFACE( this );
        m_router->SetInterface( m_iface );
    }
 
    SETTINGS_MANAGER      m_settingsManager;
    PNS::ROUTER*          m_router;
    MOCK_RULE_RESOLVER    m_ruleResolver;
    MOCK_PNS_KICAD_IFACE* m_iface;
    //std::unique_ptr<BOARD> m_board;
};
 
 
PNS::RULE_RESOLVER* MOCK_PNS_KICAD_IFACE::GetRuleResolver()
{
    return &m_testFixture->m_ruleResolver;
}
 
static void dumpObstacles( const PNS::NODE::OBSTACLES &obstacles )
{
    for( const PNS::OBSTACLE& obs : obstacles )
    {
        BOOST_TEST_MESSAGE( wxString::Format( "%p [%s] - %p [%s], clearance %d",
                obs.m_head, obs.m_head->KindStr().c_str(),
                obs.m_item, obs.m_item->KindStr().c_str(),
                obs.m_clearance ) );
    }
}
 
BOOST_FIXTURE_TEST_CASE( PNSHoleCollisions, PNS_TEST_FIXTURE )
{
    PNS::VIA* v1 = new PNS::VIA( VECTOR2I( 0, 1000000 ), PNS_LAYER_RANGE( F_Cu, B_Cu ), 50000, 10000 );
    PNS::VIA* v2 = new PNS::VIA( VECTOR2I( 0, 2000000 ), PNS_LAYER_RANGE( F_Cu, B_Cu ), 50000, 10000 );
 
    std::unique_ptr<PNS::NODE> world ( new PNS::NODE );
 
    v1->SetNet( (PNS::NET_HANDLE) 1 );
    v2->SetNet( (PNS::NET_HANDLE) 2 );
 
    world->SetMaxClearance( 10000000 );
    world->SetRuleResolver( &m_ruleResolver );
 
    world->AddRaw( v1 );
    world->AddRaw( v2 );
 
    BOOST_TEST_MESSAGE( "via to via, no violations" );
    {
        PNS::NODE::OBSTACLES obstacles;
        int count = world->QueryColliding( v1, obstacles );
        dumpObstacles( obstacles );
        BOOST_CHECK_EQUAL( obstacles.size(), 0 );
        BOOST_CHECK_EQUAL( count, 0 );
    }
 
    BOOST_TEST_MESSAGE( "via to via, forced copper to copper violation" );
    {
        PNS::NODE::OBSTACLES obstacles;
        m_ruleResolver.m_defaultClearance = 1000000;
        world->QueryColliding( v1, obstacles );
        dumpObstacles( obstacles );
 
        BOOST_CHECK_EQUAL( obstacles.size(), 1 );
        const auto& first = *obstacles.begin();
 
        BOOST_CHECK_EQUAL( first.m_head, v1 );
        BOOST_CHECK_EQUAL( first.m_item, v2 );
        BOOST_CHECK_EQUAL( first.m_clearance, m_ruleResolver.m_defaultClearance );
    }
 
    BOOST_TEST_MESSAGE( "via to via, forced hole to hole violation" );
    {
        PNS::NODE::OBSTACLES obstacles;
        m_ruleResolver.m_defaultClearance = 200000;
        m_ruleResolver.m_defaultHole2Hole = 1000000;
 
        world->QueryColliding( v1, obstacles );
        dumpObstacles( obstacles );
 
        BOOST_CHECK_EQUAL( obstacles.size(), 1 );
        auto iter = obstacles.begin();
        const auto& first = *iter++;
 
        BOOST_CHECK_EQUAL( first.m_head, v1->Hole() );
        BOOST_CHECK_EQUAL( first.m_item, v2->Hole() );
        BOOST_CHECK_EQUAL( first.m_clearance, m_ruleResolver.m_defaultHole2Hole );
    }
 
    BOOST_TEST_MESSAGE( "via to via, forced copper to hole violation" );
    {
        PNS::NODE::OBSTACLES obstacles;
        m_ruleResolver.m_defaultHole2Hole = 220000;
        m_ruleResolver.m_defaultHole2Copper = 1000000;
 
        world->QueryColliding( v1, obstacles );
        dumpObstacles( obstacles );
 
        BOOST_CHECK_EQUAL( obstacles.size(), 2 );
        auto iter = obstacles.begin();
        const auto& first = *iter++;
 
        // There is no guarantee on what order the two collisions will be in...
        BOOST_CHECK( ( first.m_head == v1 && first.m_item == v2->Hole() )
                  || ( first.m_head == v1->Hole() && first.m_item == v2 ) );
 
        BOOST_CHECK_EQUAL( first.m_clearance, m_ruleResolver.m_defaultHole2Copper );
    }
}
 
 
BOOST_FIXTURE_TEST_CASE( PNSViaBackdrillRetention, PNS_TEST_FIXTURE )
{
    PNS::VIA via( VECTOR2I( 1000, 2000 ), PNS_LAYER_RANGE( F_Cu, B_Cu ), 40000, 20000, nullptr,
                  VIATYPE::THROUGH );
    via.SetHoleLayers( PNS_LAYER_RANGE( F_Cu, In2_Cu ) );
    via.SetHolePostMachining( std::optional<PAD_DRILL_POST_MACHINING_MODE>( PAD_DRILL_POST_MACHINING_MODE::COUNTERSINK ) );
    via.SetSecondaryDrill( std::optional<int>( 12000 ) );
    via.SetSecondaryHoleLayers( std::optional<PNS_LAYER_RANGE>( PNS_LAYER_RANGE( F_Cu, In1_Cu ) ) );
    via.SetSecondaryHolePostMachining( std::optional<PAD_DRILL_POST_MACHINING_MODE>( PAD_DRILL_POST_MACHINING_MODE::NOT_POST_MACHINED ) );
 
    PNS::VIA viaCopy( via );
    std::unique_ptr<PNS::VIA> viaClone( via.Clone() );
 
    auto checkVia = [&]( const PNS::VIA& candidate )
    {
        BOOST_CHECK_EQUAL( candidate.HoleLayers().Start(), via.HoleLayers().Start() );
        BOOST_CHECK_EQUAL( candidate.HoleLayers().End(), via.HoleLayers().End() );
        BOOST_CHECK( candidate.HolePostMachining().has_value() );
        BOOST_CHECK( candidate.HolePostMachining().value() == PAD_DRILL_POST_MACHINING_MODE::COUNTERSINK );
        BOOST_CHECK( candidate.SecondaryDrill().has_value() );
        BOOST_CHECK_EQUAL( candidate.SecondaryDrill().value(), via.SecondaryDrill().value() );
        BOOST_CHECK( candidate.SecondaryHoleLayers().has_value() );
        BOOST_CHECK_EQUAL( candidate.SecondaryHoleLayers()->Start(),
                           via.SecondaryHoleLayers()->Start() );
        BOOST_CHECK_EQUAL( candidate.SecondaryHoleLayers()->End(),
                           via.SecondaryHoleLayers()->End() );
        BOOST_CHECK( candidate.SecondaryHolePostMachining().has_value() );
 
        // run this BOOST_CHECK only if possible to avoid crash
        if( candidate.SecondaryHolePostMachining().has_value() )
            BOOST_CHECK( candidate.SecondaryHolePostMachining().value() == via.SecondaryHolePostMachining().value() );
    };
 
    checkVia( viaCopy );
    checkVia( *viaClone );
}
 
 
BOOST_AUTO_TEST_CASE( PCBViaBackdrillCloneRetainsData )
{
    BOARD board;
    PCB_VIA via( &board );
 
    via.SetPrimaryDrillStartLayer( F_Cu );
    via.SetPrimaryDrillEndLayer( B_Cu );
    via.SetFrontPostMachining( std::optional<PAD_DRILL_POST_MACHINING_MODE>( PAD_DRILL_POST_MACHINING_MODE::COUNTERSINK ) );
    via.SetSecondaryDrillSize( std::optional<int>( 15000 ) );
    via.SetSecondaryDrillStartLayer( F_Cu );
    via.SetSecondaryDrillEndLayer( In2_Cu );
 
    via.SetBackPostMachining( std::optional<PAD_DRILL_POST_MACHINING_MODE>( PAD_DRILL_POST_MACHINING_MODE::COUNTERBORE ) );
    via.SetTertiaryDrillSize( std::optional<int>( 8000 ) );
    via.SetTertiaryDrillStartLayer( B_Cu );
    via.SetTertiaryDrillEndLayer( In4_Cu );
 
    PCB_VIA viaCopy( via );
    std::unique_ptr<PCB_VIA> viaClone( static_cast<PCB_VIA*>( via.Clone() ) );
 
    auto checkVia = [&]( const PCB_VIA& candidate )
    {
        BOOST_CHECK_EQUAL( candidate.GetPrimaryDrillStartLayer(), via.GetPrimaryDrillStartLayer() );
        BOOST_CHECK_EQUAL( candidate.GetPrimaryDrillEndLayer(), via.GetPrimaryDrillEndLayer() );
        BOOST_CHECK( candidate.GetFrontPostMachining().has_value() );
        BOOST_CHECK_EQUAL( static_cast<int>( candidate.GetFrontPostMachining().value() ),
                           static_cast<int>( via.GetFrontPostMachining().value() ) );
        BOOST_CHECK( candidate.GetSecondaryDrillSize().has_value() );
        BOOST_CHECK_EQUAL( candidate.GetSecondaryDrillSize().value(),
                           via.GetSecondaryDrillSize().value() );
        BOOST_CHECK_EQUAL( candidate.GetSecondaryDrillStartLayer(),
                           via.GetSecondaryDrillStartLayer() );
        BOOST_CHECK_EQUAL( candidate.GetSecondaryDrillEndLayer(),
                           via.GetSecondaryDrillEndLayer() );
 
        BOOST_CHECK( candidate.GetBackPostMachining().has_value() );
        BOOST_CHECK_EQUAL( static_cast<int>( candidate.GetBackPostMachining().value() ),
                           static_cast<int>( via.GetBackPostMachining().value() ) );
        BOOST_CHECK( candidate.GetTertiaryDrillSize().has_value() );
        BOOST_CHECK_EQUAL( candidate.GetTertiaryDrillSize().value(),
                           via.GetTertiaryDrillSize().value() );
        BOOST_CHECK_EQUAL( candidate.GetTertiaryDrillStartLayer(),
                           via.GetTertiaryDrillStartLayer() );
        BOOST_CHECK_EQUAL( candidate.GetTertiaryDrillEndLayer(),
                           via.GetTertiaryDrillEndLayer() );
    };
 
    checkVia( viaCopy );
    checkVia( *viaClone );
}
 

BOOST_AUTO_TEST_CASE( PNSLayerRangeSwapBehavior )
{
    // On a 2-layer board with FRONT_INNER_BACK mode, BoardCopperLayerCount() returns 2.
    // The code would calculate PNS_LAYER_RANGE(1, 2 - 2) = PNS_LAYER_RANGE(1, 0)
    // Since start > end, the constructor swaps them to (0, 1), which would span
    // both F_Cu and B_Cu incorrectly.
 
    PNS_LAYER_RANGE innerLayersRange2Layer( 1, 0 );  // What would happen on 2-layer board
 
    // Verify the swap behavior that causes the bug
    BOOST_CHECK_EQUAL( innerLayersRange2Layer.Start(), 0 );
    BOOST_CHECK_EQUAL( innerLayersRange2Layer.End(), 1 );
    BOOST_CHECK( innerLayersRange2Layer.Overlaps( 0 ) );  // F_Cu
    BOOST_CHECK( innerLayersRange2Layer.Overlaps( 1 ) );  // B_Cu
 
    // On a 4-layer board, inner layers are 1 and 2, so PNS_LAYER_RANGE(1, 4-2) = (1, 2)
    PNS_LAYER_RANGE innerLayersRange4Layer( 1, 2 );  // Correct for 4-layer board
 
    BOOST_CHECK_EQUAL( innerLayersRange4Layer.Start(), 1 );
    BOOST_CHECK_EQUAL( innerLayersRange4Layer.End(), 2 );
    BOOST_CHECK( !innerLayersRange4Layer.Overlaps( 0 ) ); // F_Cu - should not overlap
    BOOST_CHECK( innerLayersRange4Layer.Overlaps( 1 ) );  // In1_Cu
    BOOST_CHECK( innerLayersRange4Layer.Overlaps( 2 ) );  // In2_Cu
    BOOST_CHECK( !innerLayersRange4Layer.Overlaps( 3 ) ); // B_Cu - should not overlap
}
 

BOOST_FIXTURE_TEST_CASE( PNSInheritTrackWidthCursorProximity, PNS_TEST_FIXTURE )
{
    std::unique_ptr<PNS::NODE> world( new PNS::NODE );
    world->SetMaxClearance( 10000000 );
    world->SetRuleResolver( &m_ruleResolver );
 
    VECTOR2I padPos( 0, 0 );
    PNS::NET_HANDLE net = (PNS::NET_HANDLE) 1;
 
    // Pad at origin with a small circular shape
    PNS::SOLID* pad = new PNS::SOLID;
    pad->SetShape( new SHAPE_CIRCLE( padPos, 500000 ) );
    pad->SetPos( padPos );
    pad->SetLayers( PNS_LAYER_RANGE( F_Cu ) );
    pad->SetNet( net );
    world->AddRaw( pad );
 
    // Narrow track going right (250um width)
    int narrowWidth = 250000;
    PNS::SEGMENT* narrowSeg = new PNS::SEGMENT(
            SEG( padPos, VECTOR2I( 5000000, 0 ) ), net );
    narrowSeg->SetWidth( narrowWidth );
    narrowSeg->SetLayers( PNS_LAYER_RANGE( F_Cu ) );
    world->AddRaw( narrowSeg );
 
    // Wide track going up (500um width)
    int wideWidth = 500000;
    PNS::SEGMENT* wideSeg = new PNS::SEGMENT(
            SEG( padPos, VECTOR2I( 0, -5000000 ) ), net );
    wideSeg->SetWidth( wideWidth );
    wideSeg->SetLayers( PNS_LAYER_RANGE( F_Cu ) );
    world->AddRaw( wideSeg );
 
    int inherited = 0;
 
    // Without cursor position, should fall back to minimum width
    BOOST_CHECK( m_iface->TestInheritTrackWidth( pad, &inherited ) );
    BOOST_CHECK_EQUAL( inherited, narrowWidth );
 
    // Cursor near the narrow track (to the right) should select narrow width
    inherited = 0;
    BOOST_CHECK( m_iface->TestInheritTrackWidth( pad, &inherited,
                                                 VECTOR2I( 2000000, 0 ) ) );
    BOOST_CHECK_EQUAL( inherited, narrowWidth );
 
    // Cursor near the wide track (upward) should select wide width
    inherited = 0;
    BOOST_CHECK( m_iface->TestInheritTrackWidth( pad, &inherited,
                                                 VECTOR2I( 0, -2000000 ) ) );
    BOOST_CHECK_EQUAL( inherited, wideWidth );
 
    // Cursor slightly offset toward narrow track should still select narrow
    inherited = 0;
    BOOST_CHECK( m_iface->TestInheritTrackWidth( pad, &inherited,
                                                 VECTOR2I( 100000, 50000 ) ) );
    BOOST_CHECK_EQUAL( inherited, narrowWidth );
 
    // Cursor slightly offset toward wide track should select wide
    inherited = 0;
    BOOST_CHECK( m_iface->TestInheritTrackWidth( pad, &inherited,
                                                 VECTOR2I( 50000, -100000 ) ) );
    BOOST_CHECK_EQUAL( inherited, wideWidth );
}