OpenSTA/network/test/cpp/TestNetworkB.cc

#include <gtest/gtest.h>
#include <string>
#include "VerilogNamespace.hh"
#include "PortDirection.hh"
#include "ConcreteLibrary.hh"
#include "ConcreteNetwork.hh"
#include "HpinDrvrLoad.hh"
#include "Network.hh"
#include "PatternMatch.hh"
#include "NetworkCmp.hh"
#include "SdcNetwork.hh"

namespace sta {

////////////////////////////////////////////////////////////////
// Additional Network tests for function coverage
////////////////////////////////////////////////////////////////

// ConcreteNetwork: link and instance hierarchy tests
class ConcreteNetworkLinkedTest : public ::testing::Test {
protected:
  void SetUp() override {
    PortDirection::init();
    // Build a simple network: top instance with 2 children
    lib_ = network_.makeLibrary("test_lib", "test.lib");
    Cell *inv_cell = network_.makeCell(lib_, "INV", true, "test.lib");
    network_.makePort(inv_cell, "A");
    network_.makePort(inv_cell, "Y");
    network_.setDirection(network_.findPort(inv_cell, "A"), PortDirection::input());
    network_.setDirection(network_.findPort(inv_cell, "Y"), PortDirection::output());

    Cell *top_cell = network_.makeCell(lib_, "TOP", false, "test.lib");
    network_.makePort(top_cell, "clk");
    network_.makePort(top_cell, "data_in");
    network_.makePort(top_cell, "data_out");
    network_.setDirection(network_.findPort(top_cell, "clk"), PortDirection::input());
    network_.setDirection(network_.findPort(top_cell, "data_in"), PortDirection::input());
    network_.setDirection(network_.findPort(top_cell, "data_out"), PortDirection::output());

    // Create top instance
    Instance *top = network_.makeInstance(top_cell, "top", nullptr);
    network_.setTopInstance(top);

    // Create child instances
    u1_ = network_.makeInstance(inv_cell, "u1", top);
    u2_ = network_.makeInstance(inv_cell, "u2", top);

    // Create nets
    net1_ = network_.makeNet("n1", top);
    net2_ = network_.makeNet("n2", top);
    net3_ = network_.makeNet("n3", top);

    // Connect pins
    Port *inv_a = network_.findPort(inv_cell, "A");
    Port *inv_y = network_.findPort(inv_cell, "Y");

    pin_u1_a_ = network_.connect(u1_, inv_a, net1_);
    pin_u1_y_ = network_.connect(u1_, inv_y, net2_);
    pin_u2_a_ = network_.connect(u2_, inv_a, net2_);
    pin_u2_y_ = network_.connect(u2_, inv_y, net3_);
  }

  void TearDown() override {
    network_.clear();
  }

  ConcreteNetwork network_;
  Library *lib_;
  Instance *u1_;
  Instance *u2_;
  Net *net1_;
  Net *net2_;
  Net *net3_;
  Pin *pin_u1_a_;
  Pin *pin_u1_y_;
  Pin *pin_u2_a_;
  Pin *pin_u2_y_;
};

////////////////////////////////////////////////////////////////
// R5_ tests for NetworkNameAdapter and SdcNetwork coverage
////////////////////////////////////////////////////////////////

// Test fixture that creates a ConcreteNetwork and wraps it with
// SdcNetwork (which extends NetworkNameAdapter) for forwarding coverage.
// NetworkNameAdapter is abstract, so we test its methods through SdcNetwork.
class NetworkAdapterTest : public ::testing::Test {
protected:
  void SetUp() override {
    PortDirection::init();
    // Build a simple network
    lib_ = network_.makeLibrary("adapter_lib", "adapter.lib");
    Cell *inv_cell = network_.makeCell(lib_, "BUF", true, "adapter.lib");
    port_a_ = network_.makePort(inv_cell, "A");
    port_y_ = network_.makePort(inv_cell, "Y");
    network_.setDirection(port_a_, PortDirection::input());
    network_.setDirection(port_y_, PortDirection::output());

    Cell *top_cell = network_.makeCell(lib_, "ATOP", false, "adapter.lib");
    network_.makePort(top_cell, "in1");
    network_.makePort(top_cell, "out1");
    network_.setDirection(network_.findPort(top_cell, "in1"), PortDirection::input());
    network_.setDirection(network_.findPort(top_cell, "out1"), PortDirection::output());

    Instance *top = network_.makeInstance(top_cell, "atop", nullptr);
    network_.setTopInstance(top);

    inv_cell_ = inv_cell;
    u1_ = network_.makeInstance(inv_cell, "b1", top);
    net1_ = network_.makeNet("w1", top);
    Port *a = network_.findPort(inv_cell, "A");
    pin_b1_a_ = network_.connect(u1_, a, net1_);

    // Create sdc network (extends NetworkNameAdapter, which is abstract)
    sdc_net_ = new SdcNetwork(&network_);
  }

  void TearDown() override {
    delete sdc_net_;
    network_.clear();
  }

  ConcreteNetwork network_;
  SdcNetwork *sdc_net_;
  Library *lib_;
  Cell *inv_cell_;
  Port *port_a_;
  Port *port_y_;
  Instance *u1_;
  Net *net1_;
  Pin *pin_b1_a_;
};

// NetworkNameAdapter: topInstance forwarding
TEST_F(NetworkAdapterTest, AdapterTopInstance) {
  Instance *top = sdc_net_->topInstance();
  EXPECT_NE(top, nullptr);
  EXPECT_EQ(top, network_.topInstance());
}

// NetworkNameAdapter: name(Library) forwarding
TEST_F(NetworkAdapterTest, AdapterLibraryName) {
  EXPECT_STREQ(sdc_net_->name(lib_), "adapter_lib");
}

// NetworkNameAdapter: id(Library) forwarding
TEST_F(NetworkAdapterTest, AdapterLibraryId) {
  ObjectId adapter_id = sdc_net_->id(lib_);
  ObjectId direct_id = network_.id(lib_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: findLibrary forwarding
TEST_F(NetworkAdapterTest, AdapterFindLibrary) {
  Library *found = sdc_net_->findLibrary("adapter_lib");
  EXPECT_EQ(found, lib_);
}

// NetworkNameAdapter: findLibertyFilename forwarding (no liberty libs)
TEST_F(NetworkAdapterTest, AdapterFindLibertyFilename) {
  LibertyLibrary *found = sdc_net_->findLibertyFilename("nonexistent.lib");
  EXPECT_EQ(found, nullptr);
}

// NetworkNameAdapter: findLiberty forwarding (no liberty libs)
TEST_F(NetworkAdapterTest, AdapterFindLiberty) {
  LibertyLibrary *found = sdc_net_->findLiberty("nonexistent");
  EXPECT_EQ(found, nullptr);
}

// NetworkNameAdapter: defaultLibertyLibrary forwarding
TEST_F(NetworkAdapterTest, AdapterDefaultLibertyLibrary) {
  LibertyLibrary *def = sdc_net_->defaultLibertyLibrary();
  EXPECT_EQ(def, nullptr);
}

// NetworkNameAdapter: libraryIterator forwarding
TEST_F(NetworkAdapterTest, AdapterLibraryIterator) {
  LibraryIterator *iter = sdc_net_->libraryIterator();
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GT(count, 0);
}

// NetworkNameAdapter: libertyLibraryIterator forwarding
TEST_F(NetworkAdapterTest, AdapterLibertyLibraryIterator) {
  LibertyLibraryIterator *iter = sdc_net_->libertyLibraryIterator();
  ASSERT_NE(iter, nullptr);
  // No liberty libs loaded
  EXPECT_FALSE(iter->hasNext());
  delete iter;
}

// NetworkNameAdapter: name(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellName) {
  EXPECT_STREQ(sdc_net_->name(inv_cell_), "BUF");
}

// NetworkNameAdapter: id(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellId) {
  ObjectId adapter_id = sdc_net_->id(inv_cell_);
  ObjectId direct_id = network_.id(inv_cell_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: getAttribute(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellGetAttribute) {
  std::string val = sdc_net_->getAttribute(inv_cell_, "nonexistent");
  EXPECT_TRUE(val.empty());
}

// NetworkNameAdapter: attributeMap(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellAttributeMap) {
  const AttributeMap &map = sdc_net_->attributeMap(inv_cell_);
  // No attributes set, so map should be empty
  EXPECT_TRUE(map.empty());
}

// NetworkNameAdapter: library(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellLibrary) {
  Library *lib = sdc_net_->library(inv_cell_);
  EXPECT_EQ(lib, lib_);
}

// NetworkNameAdapter: filename(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellFilename) {
  const char *fn = sdc_net_->filename(inv_cell_);
  EXPECT_STREQ(fn, "adapter.lib");
}

// NetworkNameAdapter: findPort forwarding
TEST_F(NetworkAdapterTest, AdapterFindPort) {
  Port *found = sdc_net_->findPort(inv_cell_, "A");
  EXPECT_EQ(found, port_a_);
}

// NetworkNameAdapter: findPortsMatching forwarding
TEST_F(NetworkAdapterTest, AdapterFindPortsMatching) {
  PatternMatch pattern("*");
  PortSeq ports = sdc_net_->findPortsMatching(inv_cell_, &pattern);
  EXPECT_EQ(ports.size(), 2u);
}

// NetworkNameAdapter: isLeaf(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterCellIsLeaf) {
  EXPECT_TRUE(sdc_net_->isLeaf(inv_cell_));
}

// NetworkNameAdapter: portIterator forwarding
TEST_F(NetworkAdapterTest, AdapterPortIterator) {
  CellPortIterator *iter = sdc_net_->portIterator(inv_cell_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);
}

// NetworkNameAdapter: portBitIterator forwarding
TEST_F(NetworkAdapterTest, AdapterPortBitIterator) {
  CellPortBitIterator *iter = sdc_net_->portBitIterator(inv_cell_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);
}

// NetworkNameAdapter: portBitCount forwarding
TEST_F(NetworkAdapterTest, AdapterPortBitCount) {
  int count = sdc_net_->portBitCount(inv_cell_);
  EXPECT_EQ(count, 2);
}

// NetworkNameAdapter: name(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortName) {
  EXPECT_STREQ(sdc_net_->name(port_a_), "A");
}

// NetworkNameAdapter: id(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortId) {
  ObjectId adapter_id = sdc_net_->id(port_a_);
  ObjectId direct_id = network_.id(port_a_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: cell(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortCell) {
  Cell *cell = sdc_net_->cell(port_a_);
  EXPECT_EQ(cell, inv_cell_);
}

// NetworkNameAdapter: direction(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortDirection) {
  PortDirection *dir = sdc_net_->direction(port_a_);
  EXPECT_EQ(dir, PortDirection::input());
}

// NetworkNameAdapter: isBundle(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortIsBundle) {
  EXPECT_FALSE(sdc_net_->isBundle(port_a_));
}

// NetworkNameAdapter: isBus(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortIsBus) {
  EXPECT_FALSE(sdc_net_->isBus(port_a_));
}

// NetworkNameAdapter: size(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortSize) {
  EXPECT_EQ(sdc_net_->size(port_a_), 1);
}

// NetworkNameAdapter: busName(Port) scalar forwarding
TEST_F(NetworkAdapterTest, AdapterPortBusName) {
  const char *bn = sdc_net_->busName(port_a_);
  // Scalar port returns name (not nullptr) through SdcNetwork
  EXPECT_NE(bn, nullptr);
}

// NetworkNameAdapter: fromIndex(Port) forwarding (scalar ports return -1)
TEST_F(NetworkAdapterTest, AdapterPortFromIndex) {
  int idx = sdc_net_->fromIndex(port_a_);
  EXPECT_EQ(idx, -1);
}

// NetworkNameAdapter: toIndex(Port) forwarding (scalar ports return -1)
TEST_F(NetworkAdapterTest, AdapterPortToIndex) {
  int idx = sdc_net_->toIndex(port_a_);
  EXPECT_EQ(idx, -1);
}

// NetworkNameAdapter: hasMembers(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortHasMembers) {
  EXPECT_FALSE(sdc_net_->hasMembers(port_a_));
}

// (R5_AdapterPortFindMember removed: segfaults on scalar port)
// (R5_AdapterPortFindBusBit removed: segfaults on scalar port)

// NetworkNameAdapter: id(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceId) {
  ObjectId adapter_id = sdc_net_->id(u1_);
  ObjectId direct_id = network_.id(u1_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: cell(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceCell) {
  Cell *cell = sdc_net_->cell(u1_);
  EXPECT_EQ(cell, inv_cell_);
}

// NetworkNameAdapter: getAttribute(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceGetAttribute) {
  std::string val = sdc_net_->getAttribute(u1_, "nonexistent");
  EXPECT_TRUE(val.empty());
}

// NetworkNameAdapter: attributeMap(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceAttributeMap) {
  const AttributeMap &map = sdc_net_->attributeMap(u1_);
  // No attributes set, so map should be empty
  EXPECT_TRUE(map.empty());
}

// NetworkNameAdapter: parent(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceParent) {
  Instance *parent = sdc_net_->parent(u1_);
  EXPECT_EQ(parent, network_.topInstance());
}

// NetworkNameAdapter: isLeaf(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceIsLeaf) {
  EXPECT_TRUE(sdc_net_->isLeaf(u1_));
}

// NetworkNameAdapter: findPin(Instance, Port) forwarding
TEST_F(NetworkAdapterTest, AdapterFindPinByPort) {
  Pin *pin = sdc_net_->findPin(u1_, port_a_);
  EXPECT_EQ(pin, pin_b1_a_);
}

// (R5_AdapterFindPinByLibertyPort removed: segfaults with nullptr LibertyPort)

// NetworkNameAdapter: childIterator forwarding
TEST_F(NetworkAdapterTest, AdapterChildIterator) {
  Instance *top = sdc_net_->topInstance();
  InstanceChildIterator *iter = sdc_net_->childIterator(top);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 1);
}

// NetworkNameAdapter: pinIterator(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstancePinIterator) {
  InstancePinIterator *iter = sdc_net_->pinIterator(u1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// NetworkNameAdapter: netIterator(Instance) forwarding
TEST_F(NetworkAdapterTest, AdapterInstanceNetIterator) {
  Instance *top = sdc_net_->topInstance();
  InstanceNetIterator *iter = sdc_net_->netIterator(top);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// NetworkNameAdapter: id(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinId) {
  ObjectId adapter_id = sdc_net_->id(pin_b1_a_);
  ObjectId direct_id = network_.id(pin_b1_a_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: port(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinPort) {
  Port *port = sdc_net_->port(pin_b1_a_);
  EXPECT_EQ(port, port_a_);
}

// NetworkNameAdapter: instance(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinInstance) {
  Instance *inst = sdc_net_->instance(pin_b1_a_);
  EXPECT_EQ(inst, u1_);
}

// NetworkNameAdapter: net(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinNet) {
  Net *net = sdc_net_->net(pin_b1_a_);
  EXPECT_EQ(net, net1_);
}

// NetworkNameAdapter: term(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinTerm) {
  Term *term = sdc_net_->term(pin_b1_a_);
  // leaf instance pins have no term
  EXPECT_EQ(term, nullptr);
}

// NetworkNameAdapter: direction(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinDirection) {
  PortDirection *dir = sdc_net_->direction(pin_b1_a_);
  EXPECT_EQ(dir, PortDirection::input());
}

// NetworkNameAdapter: vertexId(Pin) forwarding
TEST_F(NetworkAdapterTest, AdapterPinVertexId) {
  VertexId vid = sdc_net_->vertexId(pin_b1_a_);
  // VertexId is a valid value (could be 0 for unset)
  EXPECT_GE(vid, 0u);
}

// NetworkNameAdapter: setVertexId forwarding
TEST_F(NetworkAdapterTest, AdapterSetVertexId) {
  sdc_net_->setVertexId(pin_b1_a_, 42);
  VertexId vid = sdc_net_->vertexId(pin_b1_a_);
  EXPECT_EQ(vid, 42u);
}

// NetworkNameAdapter: id(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetId) {
  ObjectId adapter_id = sdc_net_->id(net1_);
  ObjectId direct_id = network_.id(net1_);
  EXPECT_EQ(adapter_id, direct_id);
}

// NetworkNameAdapter: instance(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetInstance) {
  Instance *inst = sdc_net_->instance(net1_);
  EXPECT_EQ(inst, network_.topInstance());
}

// NetworkNameAdapter: isPower(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetIsPower) {
  EXPECT_FALSE(sdc_net_->isPower(net1_));
}

// NetworkNameAdapter: isGround(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetIsGround) {
  EXPECT_FALSE(sdc_net_->isGround(net1_));
}

// NetworkNameAdapter: pinIterator(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetPinIterator) {
  NetPinIterator *iter = sdc_net_->pinIterator(net1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// NetworkNameAdapter: termIterator(Net) forwarding
TEST_F(NetworkAdapterTest, AdapterNetTermIterator) {
  NetTermIterator *iter = sdc_net_->termIterator(net1_);
  ASSERT_NE(iter, nullptr);
  delete iter;
}

// NetworkNameAdapter: constantPinIterator forwarding
TEST_F(NetworkAdapterTest, AdapterConstantPinIterator) {
  ConstantPinIterator *iter = sdc_net_->constantPinIterator();
  ASSERT_NE(iter, nullptr);
  delete iter;
}

// NetworkNameAdapter: pathDivider forwarding
TEST_F(NetworkAdapterTest, AdapterPathDivider) {
  char div = sdc_net_->pathDivider();
  EXPECT_EQ(div, network_.pathDivider());
}

// NetworkNameAdapter: setPathDivider forwarding
TEST_F(NetworkAdapterTest, AdapterSetPathDivider) {
  sdc_net_->setPathDivider('/');
  EXPECT_EQ(network_.pathDivider(), '/');
}

// NetworkNameAdapter: pathEscape forwarding
TEST_F(NetworkAdapterTest, AdapterPathEscape) {
  char esc = sdc_net_->pathEscape();
  EXPECT_EQ(esc, network_.pathEscape());
}

// NetworkNameAdapter: setPathEscape forwarding
TEST_F(NetworkAdapterTest, AdapterSetPathEscape) {
  sdc_net_->setPathEscape('~');
  EXPECT_EQ(network_.pathEscape(), '~');
}

// NetworkNameAdapter: isEditable forwarding
TEST_F(NetworkAdapterTest, AdapterIsEditable) {
  EXPECT_TRUE(sdc_net_->isEditable());
}

// NetworkNameAdapter: libertyCell(Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterLibertyCellFromCell) {
  LibertyCell *lc = sdc_net_->libertyCell(inv_cell_);
  EXPECT_EQ(lc, nullptr);
}

// NetworkNameAdapter: libertyCell(const Cell) forwarding
TEST_F(NetworkAdapterTest, AdapterConstLibertyCellFromCell) {
  const LibertyCell *lc = sdc_net_->libertyCell(static_cast<const Cell*>(inv_cell_));
  EXPECT_EQ(lc, nullptr);
}

// NetworkNameAdapter: cell(LibertyCell*) forwarding
TEST_F(NetworkAdapterTest, AdapterCellFromLibertyCell) {
  Cell *c = sdc_net_->cell(static_cast<LibertyCell*>(nullptr));
  EXPECT_EQ(c, nullptr);
}

// NetworkNameAdapter: cell(const LibertyCell*) forwarding
TEST_F(NetworkAdapterTest, AdapterCellFromConstLibertyCell) {
  const Cell *c = sdc_net_->cell(static_cast<const LibertyCell*>(nullptr));
  EXPECT_EQ(c, nullptr);
}

// NetworkNameAdapter: mergedInto forwarding
TEST_F(NetworkAdapterTest, AdapterMergedInto) {
  Net *merged = sdc_net_->mergedInto(net1_);
  EXPECT_EQ(merged, nullptr);
}

// NetworkNameAdapter: makeNet forwarding
TEST_F(NetworkAdapterTest, AdapterMakeNet) {
  Instance *top = sdc_net_->topInstance();
  Net *new_net = sdc_net_->makeNet("adapter_net", top);
  EXPECT_NE(new_net, nullptr);
}

// NetworkNameAdapter: connect(Instance, Port, Net) forwarding
TEST_F(NetworkAdapterTest, AdapterConnect) {
  Instance *top = sdc_net_->topInstance();
  Net *new_net = sdc_net_->makeNet("connect_net", top);
  Pin *pin = sdc_net_->connect(u1_, port_y_, new_net);
  EXPECT_NE(pin, nullptr);
}

// NetworkNameAdapter: disconnectPin forwarding
TEST_F(NetworkAdapterTest, AdapterDisconnectPin) {
  Instance *top = sdc_net_->topInstance();
  Net *new_net = sdc_net_->makeNet("disc_net", top);
  Pin *pin = sdc_net_->connect(u1_, port_y_, new_net);
  ASSERT_NE(pin, nullptr);
  sdc_net_->disconnectPin(pin);
  // After disconnect, net(pin) should be nullptr
  EXPECT_EQ(sdc_net_->net(pin), nullptr);
}

// NetworkNameAdapter: deletePin forwarding
TEST_F(NetworkAdapterTest, AdapterDeletePin) {
  Instance *top = sdc_net_->topInstance();
  Net *new_net = sdc_net_->makeNet("delpin_net", top);
  Pin *pin = sdc_net_->connect(u1_, port_y_, new_net);
  ASSERT_NE(pin, nullptr);
  sdc_net_->disconnectPin(pin);
  sdc_net_->deletePin(pin);
  // Just verify it doesn't crash
}

// NetworkNameAdapter: mergeInto forwarding
TEST_F(NetworkAdapterTest, AdapterMergeInto) {
  Instance *top = sdc_net_->topInstance();
  Net *net_a = sdc_net_->makeNet("merge_a", top);
  Net *net_b = sdc_net_->makeNet("merge_b", top);
  sdc_net_->mergeInto(net_a, net_b);
  Net *merged = sdc_net_->mergedInto(net_a);
  EXPECT_EQ(merged, net_b);
}

// SdcNetwork: constructor and basic forwarding
TEST_F(NetworkAdapterTest, SdcNetworkTopInstance) {
  Instance *top = sdc_net_->topInstance();
  EXPECT_NE(top, nullptr);
  EXPECT_EQ(top, network_.topInstance());
}

// SdcNetwork: name(Port) forwarding with sdc namespace
TEST_F(NetworkAdapterTest, SdcNetworkPortName) {
  const char *name = sdc_net_->name(port_a_);
  EXPECT_NE(name, nullptr);
}

// SdcNetwork: busName(Port) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkPortBusName) {
  const char *bn = sdc_net_->busName(port_a_);
  // SdcNetwork busName returns name for scalar port
  EXPECT_NE(bn, nullptr);
}

// SdcNetwork: findPort forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindPort) {
  Port *found = sdc_net_->findPort(inv_cell_, "A");
  EXPECT_EQ(found, port_a_);
}

// SdcNetwork: findPortsMatching forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindPortsMatching) {
  PatternMatch pattern("*");
  PortSeq ports = sdc_net_->findPortsMatching(inv_cell_, &pattern);
  EXPECT_EQ(ports.size(), 2u);
}

// SdcNetwork: findNet(Instance, name) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindNet) {
  Instance *top = sdc_net_->topInstance();
  Net *found = sdc_net_->findNet(top, "w1");
  EXPECT_EQ(found, net1_);
}

// SdcNetwork: name(Instance) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkInstanceName) {
  const char *name = sdc_net_->name(u1_);
  EXPECT_NE(name, nullptr);
}

// SdcNetwork: pathName(Instance) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkInstancePathName) {
  const char *path = sdc_net_->pathName(u1_);
  EXPECT_NE(path, nullptr);
}

// SdcNetwork: pathName(Pin) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkPinPathName) {
  const char *path = sdc_net_->pathName(pin_b1_a_);
  EXPECT_NE(path, nullptr);
}

// SdcNetwork: portName(Pin) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkPinPortName) {
  const char *port_name = sdc_net_->portName(pin_b1_a_);
  EXPECT_NE(port_name, nullptr);
}

// SdcNetwork: name(Net) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkNetName) {
  const char *name = sdc_net_->name(net1_);
  EXPECT_NE(name, nullptr);
}

// SdcNetwork: pathName(Net) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkNetPathName) {
  const char *path = sdc_net_->pathName(net1_);
  EXPECT_NE(path, nullptr);
}

// SdcNetwork: findChild forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindChild) {
  Instance *top = sdc_net_->topInstance();
  Instance *child = sdc_net_->findChild(top, "b1");
  EXPECT_EQ(child, u1_);
}

// SdcNetwork: findInstance by path name
TEST_F(NetworkAdapterTest, SdcNetworkFindInstance) {
  Instance *found = sdc_net_->findInstance("b1");
  EXPECT_EQ(found, u1_);
}

// SdcNetwork: findPin(path) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindPinPath) {
  Pin *found = sdc_net_->findPin("b1/A");
  EXPECT_EQ(found, pin_b1_a_);
}

// SdcNetwork: findPin(Instance, port_name) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindPinInstancePort) {
  Pin *found = sdc_net_->findPin(u1_, "A");
  EXPECT_EQ(found, pin_b1_a_);
}

// SdcNetwork: findNet(path) forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindNetPath) {
  Net *found = sdc_net_->findNet("w1");
  EXPECT_EQ(found, net1_);
}

// SdcNetwork: findNetRelative forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindNetRelative) {
  Instance *top = sdc_net_->topInstance();
  Net *found = sdc_net_->findNetRelative(top, "w1");
  EXPECT_EQ(found, net1_);
}

// SdcNetwork: findNetsMatching forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindNetsMatching) {
  Instance *top = sdc_net_->topInstance();
  PatternMatch pattern("w*");
  NetSeq nets = sdc_net_->findNetsMatching(top, &pattern);
  EXPECT_GE(nets.size(), 1u);
}

// SdcNetwork: findInstNetsMatching forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindInstNetsMatching) {
  Instance *top = sdc_net_->topInstance();
  PatternMatch pattern("w*");
  NetSeq nets;
  sdc_net_->findInstNetsMatching(top, &pattern, nets);
  EXPECT_GE(nets.size(), 1u);
}

// SdcNetwork: findInstancesMatching forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindInstancesMatching) {
  Instance *top = sdc_net_->topInstance();
  PatternMatch pattern("b*");
  InstanceSeq insts = sdc_net_->findInstancesMatching(top, &pattern);
  EXPECT_GE(insts.size(), 1u);
}

// SdcNetwork: findPinsMatching forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindPinsMatching) {
  PatternMatch pattern("b1/A");
  PinSeq pins = sdc_net_->findPinsMatching(network_.topInstance(), &pattern);
  EXPECT_GE(pins.size(), 1u);
}

// SdcNetwork: findInstanceRelative forwarding
TEST_F(NetworkAdapterTest, SdcNetworkFindInstanceRelative) {
  Instance *top = sdc_net_->topInstance();
  Instance *found = sdc_net_->findInstanceRelative(top, "b1");
  EXPECT_EQ(found, u1_);
}

// SdcNetwork: makeNet forwarding
TEST_F(NetworkAdapterTest, SdcNetworkMakeNet) {
  Instance *top = sdc_net_->topInstance();
  Net *new_net = sdc_net_->makeNet("sdc_net_new", top);
  EXPECT_NE(new_net, nullptr);
}

// NetworkNameAdapter: location forwarding
TEST_F(NetworkAdapterTest, AdapterLocation) {
  double x, y;
  bool exists;
  sdc_net_->location(pin_b1_a_, x, y, exists);
  EXPECT_FALSE(exists);
}

// NetworkNameAdapter: libertyPort forwarding (non-liberty port)
TEST_F(NetworkAdapterTest, AdapterLibertyPort) {
  LibertyPort *lp = sdc_net_->libertyPort(port_a_);
  EXPECT_EQ(lp, nullptr);
}

////////////////////////////////////////////////////////////////
// R6_ tests for additional network coverage
////////////////////////////////////////////////////////////////

// ConcreteNetwork: addConstantNet then verify iteration
TEST_F(ConcreteNetworkLinkedTest, AddConstantAndIterate) {
  network_.addConstantNet(net1_, LogicValue::one);
  ConstantPinIterator *iter = network_.constantPinIterator();
  EXPECT_NE(iter, nullptr);
  bool found = false;
  while (iter->hasNext()) {
    const Pin *pin;
    LogicValue val;
    iter->next(pin, val);
    if (val == LogicValue::one)
      found = true;
  }
  delete iter;
  EXPECT_TRUE(found);
}

// ConcreteInstance: cell() accessor
TEST_F(ConcreteNetworkLinkedTest, ConcreteInstanceCell) {
  Cell *cell = network_.cell(u1_);
  EXPECT_NE(cell, nullptr);
  EXPECT_STREQ(network_.name(cell), "INV");
}

// ConcreteInstance: findChild returns nullptr on leaf
TEST_F(ConcreteNetworkLinkedTest, FindChildOnLeaf) {
  // u1_ is a leaf instance, should have no children
  Instance *child = network_.findChild(u1_, "nonexistent");
  EXPECT_EQ(child, nullptr);
}

// ConcreteInstance: findPin(Port) with existing port
TEST_F(ConcreteNetworkLinkedTest, FindPinByPortDirect) {
  Cell *cell = network_.cell(u1_);
  Port *port_a = network_.findPort(cell, "A");
  Pin *pin = network_.findPin(u1_, port_a);
  EXPECT_EQ(pin, pin_u1_a_);
}

// ConcreteInstance: deleteChild
TEST_F(ConcreteNetworkLinkedTest, DeleteChild) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *top = network_.topInstance();
  Instance *temp = network_.makeInstance(inv_cell, "temp_child", top);
  EXPECT_NE(network_.findChild(top, "temp_child"), nullptr);
  // Need to delete the instance properly through the network
  network_.deleteInstance(temp);
  EXPECT_EQ(network_.findChild(top, "temp_child"), nullptr);
}

// ConcreteInstance: addNet and deleteNet (via network)
TEST_F(ConcreteNetworkLinkedTest, AddAndDeleteNet) {
  Instance *top = network_.topInstance();
  Net *new_net = network_.makeNet("r6_net", top);
  EXPECT_NE(new_net, nullptr);
  EXPECT_NE(network_.findNet(top, "r6_net"), nullptr);
  network_.deleteNet(new_net);
  EXPECT_EQ(network_.findNet(top, "r6_net"), nullptr);
}

// ConcreteInstance: setCell (replaceCell exercises setCell)
TEST_F(ConcreteNetworkLinkedTest, SetCellViaReplace) {
  Cell *buf_cell = network_.makeCell(lib_, "BUF_R6", true, "test.lib");
  network_.makePort(buf_cell, "A");
  network_.makePort(buf_cell, "Y");
  network_.setDirection(network_.findPort(buf_cell, "A"), PortDirection::input());
  network_.setDirection(network_.findPort(buf_cell, "Y"), PortDirection::output());

  // Disconnect pins before replacing cell
  network_.disconnectPin(pin_u1_a_);
  network_.disconnectPin(pin_u1_y_);
  network_.replaceCell(u1_, buf_cell);
  Cell *new_cell = network_.cell(u1_);
  EXPECT_STREQ(network_.name(new_cell), "BUF_R6");
}

// ConcretePin: name() via Network base class
TEST_F(ConcreteNetworkLinkedTest, ConcretePinName) {
  const Network &net = network_;
  const char *name = net.name(pin_u1_a_);
  EXPECT_NE(name, nullptr);
  // Pin name is instance/port
  std::string name_str(name);
  EXPECT_NE(name_str.find("A"), std::string::npos);
}

// ConcretePin: setVertexId
TEST_F(ConcreteNetworkLinkedTest, PinSetVertexIdMultiple) {
  network_.setVertexId(pin_u1_a_, 100);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 100u);
  network_.setVertexId(pin_u1_a_, 200);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 200u);
  network_.setVertexId(pin_u1_a_, 0);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 0u);
}

// ConcreteTerm: name() via Network base class
TEST_F(ConcreteNetworkLinkedTest, ConcreteTermName) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u3 = network_.makeInstance(inv_cell, "u3_term", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("term_net", network_.topInstance());
  Pin *pin = network_.makePin(u3, port_a, net);
  Term *term = network_.makeTerm(pin, net);
  EXPECT_NE(term, nullptr);
  const Network &base_net = network_;
  const char *tname = base_net.name(term);
  EXPECT_NE(tname, nullptr);
}

// Network: name(Term), pathName(Term), portName(Term)
TEST_F(ConcreteNetworkLinkedTest, TermPathAndPortName) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u4 = network_.makeInstance(inv_cell, "u4_term", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("term_net2", network_.topInstance());
  Pin *pin = network_.makePin(u4, port_a, net);
  Term *term = network_.makeTerm(pin, net);
  EXPECT_NE(term, nullptr);

  const Network &base_net = network_;
  const char *tname = base_net.name(term);
  EXPECT_NE(tname, nullptr);

  const char *tpath = base_net.pathName(term);
  EXPECT_NE(tpath, nullptr);

  const char *tport = base_net.portName(term);
  EXPECT_NE(tport, nullptr);
}

// Network: id(Term)
TEST_F(ConcreteNetworkLinkedTest, TermId2) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u5 = network_.makeInstance(inv_cell, "u5_term", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("term_net3", network_.topInstance());
  Pin *pin = network_.makePin(u5, port_a, net);
  Term *term = network_.makeTerm(pin, net);
  ObjectId id = network_.id(term);
  EXPECT_GE(id, 0u);
}

// Network: findPin by string name on instance
TEST_F(ConcreteNetworkLinkedTest, FindPinByStringName) {
  Pin *found = network_.findPin(u1_, "A");
  EXPECT_EQ(found, pin_u1_a_);
  Pin *found_y = network_.findPin(u1_, "Y");
  EXPECT_EQ(found_y, pin_u1_y_);
  Pin *notfound = network_.findPin(u1_, "nonexistent");
  EXPECT_EQ(notfound, nullptr);
}

// Network: findNet by instance and name
TEST_F(ConcreteNetworkLinkedTest, FindNetByInstanceName) {
  Instance *top = network_.topInstance();
  Net *found = network_.findNet(top, "n1");
  EXPECT_EQ(found, net1_);
  Net *found2 = network_.findNet(top, "n2");
  EXPECT_EQ(found2, net2_);
  Net *notfound = network_.findNet(top, "nonexistent");
  EXPECT_EQ(notfound, nullptr);
}

// Network: findNetsMatching comprehensive
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatchingComprehensive) {
  Instance *top = network_.topInstance();
  PatternMatch pattern_all("*");
  NetSeq all_matches = network_.findNetsMatching(top, &pattern_all);
  EXPECT_GE(all_matches.size(), 3u);
}

// Network: hasMembersOnScalarPort
TEST_F(ConcreteNetworkLinkedTest, HasMembersScalar) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  EXPECT_FALSE(network_.hasMembers(port_a));
}

// Network: hasMembersOnBusPort
TEST_F(ConcreteNetworkLinkedTest, HasMembersBusPort) {
  ConcreteLibrary *clib = reinterpret_cast<ConcreteLibrary*>(lib_);
  clib->setBusBrkts('[', ']');
  Cell *cell = network_.makeCell(lib_, "R6_BUS_TEST", true, "test.lib");
  Port *bus = network_.makeBusPort(cell, "D", 3, 0);
  EXPECT_TRUE(network_.hasMembers(bus));
}

// Network: libertyCell from const cell
TEST_F(ConcreteNetworkLinkedTest, LibertyCellFromConstCell) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  const Cell *cc = inv_cell;
  const LibertyCell *lcell = network_.libertyCell(cc);
  EXPECT_EQ(lcell, nullptr);
}

// ConcreteNet: destructor (via deleteNet which calls ~ConcreteNet)
TEST_F(ConcreteNetworkLinkedTest, NetDestructor) {
  Instance *top = network_.topInstance();
  Net *temp_net = network_.makeNet("r6_temp_net", top);
  EXPECT_NE(network_.findNet(top, "r6_temp_net"), nullptr);
  network_.deleteNet(temp_net);
  EXPECT_EQ(network_.findNet(top, "r6_temp_net"), nullptr);
}

// ConcreteNet: addPin, addTerm via connect and makeTerm
TEST_F(ConcreteNetworkLinkedTest, NetAddPinAndTerm) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u6 = network_.makeInstance(inv_cell, "u6", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("r6_connect_net", network_.topInstance());

  // connect adds pin to net
  Pin *pin = network_.connect(u6, port_a, net);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(network_.net(pin), net);

  // makeTerm adds term to net
  Term *term = network_.makeTerm(pin, net);
  EXPECT_NE(term, nullptr);
}

// ConcreteNet: deleteTerm (via disconnect which removes term)
TEST_F(ConcreteNetworkLinkedTest, NetTermIteratorAfterConnect) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u7 = network_.makeInstance(inv_cell, "u7", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("r6_term_iter_net", network_.topInstance());
  Pin *pin = network_.makePin(u7, port_a, net);
  Term *term = network_.makeTerm(pin, net);
  EXPECT_NE(term, nullptr);

  // Iterate terms
  NetTermIterator *iter = network_.termIterator(net);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// ConcreteInstancePinIterator constructor exercise
TEST_F(ConcreteNetworkLinkedTest, InstancePinIteratorExercise) {
  InstancePinIterator *iter = network_.pinIterator(u1_);
  ASSERT_NE(iter, nullptr);
  PinSeq pins;
  while (iter->hasNext()) {
    pins.push_back(iter->next());
  }
  delete iter;
  EXPECT_EQ(pins.size(), 2u);
}

// ConcreteNetPinIterator constructor
TEST_F(ConcreteNetworkLinkedTest, NetPinIteratorExercise) {
  // net1_ has 1 pin (u1_A)
  NetPinIterator *iter = network_.pinIterator(net1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 1);
}

// ConcreteNetTermIterator
TEST_F(ConcreteNetworkLinkedTest, NetTermIteratorEmpty) {
  // net3_ has pins but no terms (leaf connections)
  NetTermIterator *iter = network_.termIterator(net3_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 0);
}

// ConcreteLibertyLibraryIterator (exercises constructor and destructor)
TEST(ConcreteNetworkExtraTest, LibertyLibIteratorEmpty) {
  ConcreteNetwork network;
  LibertyLibraryIterator *iter = network.libertyLibraryIterator();
  ASSERT_NE(iter, nullptr);
  EXPECT_FALSE(iter->hasNext());
  delete iter;
}

// ConcreteLibertyLibraryIterator with one liberty library
TEST(ConcreteNetworkExtraTest, LibertyLibIteratorWithLib) {
  ConcreteNetwork network;
  network.makeLibertyLibrary("r6_lib", "r6.lib");
  LibertyLibraryIterator *iter = network.libertyLibraryIterator();
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 1);
}

// ConcreteLibraryIterator1 (exercises constructor)
TEST(ConcreteNetworkExtraTest, LibraryIteratorMultiple) {
  ConcreteNetwork network;
  network.makeLibrary("r6_lib1", "r6_1.lib");
  network.makeLibrary("r6_lib2", "r6_2.lib");
  network.makeLibrary("r6_lib3", "r6_3.lib");
  LibraryIterator *iter = network.libraryIterator();
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 3);
}

// ConcreteCellPortIterator1 (exercises constructor)
TEST(ConcreteCellTest, PortIterator1) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  ConcreteCell *cell = lib.makeCell("R6_AND3", true, "");
  cell->makePort("A");
  cell->makePort("B");
  cell->makePort("C");
  cell->makePort("Y");

  ConcreteCellPortIterator *iter = cell->portIterator();
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 4);
}

// ConcreteCellPortBitIterator (with bus ports)
TEST(ConcreteCellTest, PortBitIteratorWithBus) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R6_REG8", true, "");
  cell->makePort("CLK");
  cell->makeBusPort("D", 7, 0);  // 8-bit bus
  cell->makePort("RST");

  ConcreteCellPortBitIterator *iter = cell->portBitIterator();
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // CLK(1) + D[0..7](8) + RST(1) = 10
  EXPECT_EQ(count, 10);
}

// ConcreteCellPortBitIterator1 exercise
TEST(ConcreteCellTest, PortBitIterator1Simple) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  ConcreteCell *cell = lib.makeCell("R6_INV2", true, "");
  cell->makePort("A");
  cell->makePort("Y");

  ConcreteCellPortBitIterator *iter = cell->portBitIterator();
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);
}

// ConcretePortMemberIterator1 exercise
TEST(ConcretePortTest, MemberIteratorBus) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R6_REG4", true, "");
  ConcretePort *bus = cell->makeBusPort("D", 3, 0);
  ConcretePortMemberIterator *iter = bus->memberIterator();
  int count = 0;
  while (iter->hasNext()) {
    ConcretePort *member = iter->next();
    EXPECT_NE(member, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 4);
}

// ConcreteInstanceChildIterator exercise
TEST_F(ConcreteNetworkLinkedTest, ChildIteratorExercise) {
  Instance *top = network_.topInstance();
  InstanceChildIterator *iter = network_.childIterator(top);
  ASSERT_NE(iter, nullptr);
  InstanceSeq children;
  while (iter->hasNext()) {
    children.push_back(iter->next());
  }
  delete iter;
  EXPECT_EQ(children.size(), 2u);
}

// Network: connect with LibertyPort (null liberty port variant)
TEST_F(ConcreteNetworkLinkedTest, ConnectWithPort) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u8 = network_.makeInstance(inv_cell, "u8_conn", network_.topInstance());
  Port *port_y = network_.findPort(inv_cell, "Y");
  Net *net = network_.makeNet("r6_conn_net", network_.topInstance());
  Pin *pin = network_.connect(u8, port_y, net);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(network_.net(pin), net);
}

// Network: deletePin (exercises ConcreteInstance::deletePin)
TEST_F(ConcreteNetworkLinkedTest, DeletePinExercise) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u9 = network_.makeInstance(inv_cell, "u9_delpin", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("r6_delpin_net", network_.topInstance());
  Pin *pin = network_.connect(u9, port_a, net);
  EXPECT_NE(pin, nullptr);
  network_.disconnectPin(pin);
  network_.deletePin(pin);
  Pin *found = network_.findPin(u9, "A");
  EXPECT_EQ(found, nullptr);
}

// BusPort: default constructor exercises (via makeBusPort)
TEST(ConcretePortTest, BusPortDefaultCtor) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R6_BUSTEST", true, "");
  ConcretePort *bus = cell->makeBusPort("Q", 0, 3);
  EXPECT_NE(bus, nullptr);
  EXPECT_TRUE(bus->isBus());
  EXPECT_EQ(bus->fromIndex(), 0);
  EXPECT_EQ(bus->toIndex(), 3);
  EXPECT_EQ(bus->size(), 4);
}

// BusPort: setDirection propagates to members
TEST(ConcretePortTest, BusPortSetDirection) {
  PortDirection::init();
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R6_BUSDIR", true, "");
  ConcretePort *bus = cell->makeBusPort("D", 1, 0);
  bus->setDirection(PortDirection::output());
  EXPECT_EQ(bus->direction(), PortDirection::output());
  ConcretePort *bit0 = bus->findBusBit(0);
  if (bit0) {
    EXPECT_EQ(bit0->direction(), PortDirection::output());
  }
}

// NetworkNameAdapter: makeLibertyLibrary forwarding
TEST_F(NetworkAdapterTest, AdapterMakeLibertyLibrary) {
  LibertyLibrary *lib = sdc_net_->makeLibertyLibrary("r6_lib", "r6.lib");
  EXPECT_NE(lib, nullptr);
}

// NetworkNameAdapter: findCellsMatching forwarding
TEST_F(NetworkAdapterTest, AdapterFindCellsMatching) {
  PatternMatch pattern("BUF*");
  CellSeq cells = sdc_net_->findCellsMatching(lib_, &pattern);
  EXPECT_GE(cells.size(), 1u);
}

// NetworkNameAdapter: isLinked forwarding
TEST_F(NetworkAdapterTest, AdapterIsLinked) {
  EXPECT_TRUE(sdc_net_->isLinked());
}

// NetworkNameAdapter: connect(Instance, LibertyPort, Net) cannot be tested
// without an actual LibertyPort, so skip.

// Network: findPin(Instance, Port) with non-matching port
TEST_F(ConcreteNetworkLinkedTest, FindPinNonMatchingPort) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_y = network_.findPort(inv_cell, "Y");
  // u1_ is connected on A and Y, find Y pin
  Pin *pin = network_.findPin(u1_, port_y);
  EXPECT_EQ(pin, pin_u1_y_);
}

// Network: findPinsMatching with no match
TEST_F(ConcreteNetworkLinkedTest, FindPinsMatchingNoMatch) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("nonexistent/*");
  PinSeq pins = network_.findPinsMatching(top, &pattern);
  EXPECT_EQ(pins.size(), 0u);
}

// Network: findNetsMatching with no match
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatchingNoMatch) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("zzz*");
  NetSeq matches = network_.findNetsMatching(top, &pattern);
  EXPECT_EQ(matches.size(), 0u);
}

// Network: findInstancesMatching with no match
TEST_F(ConcreteNetworkLinkedTest, FindInstancesMatchingNoMatch) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("zzz*");
  InstanceSeq matches = network_.findInstancesMatching(top, &pattern);
  EXPECT_EQ(matches.size(), 0u);
}

// ConcreteNetwork: initPins via makePins on new instance
TEST_F(ConcreteNetworkLinkedTest, InitPinsExercise) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u10 = network_.makeInstance(inv_cell, "u10_init", network_.topInstance());
  network_.makePins(u10);
  Pin *pin_a = network_.findPin(u10, "A");
  Pin *pin_y = network_.findPin(u10, "Y");
  EXPECT_NE(pin_a, nullptr);
  EXPECT_NE(pin_y, nullptr);
}

// ConcreteNetwork: mergeInto and mergedInto cycle
TEST_F(ConcreteNetworkLinkedTest, MergeIntoCycle) {
  Instance *top = network_.topInstance();
  Net *na = network_.makeNet("r6_merge_a", top);
  Net *nb = network_.makeNet("r6_merge_b", top);
  network_.mergeInto(na, nb);
  EXPECT_EQ(network_.mergedInto(na), nb);
  EXPECT_EQ(network_.mergedInto(nb), nullptr);
}

// ConcreteNetwork: connect via LibertyPort (exercises connect(Inst, LibertyPort, Net))
// This goes through ConcreteNetwork::connect which dispatches to connect(Inst, Port, Net)
// Can't easily test without real LibertyPort, skip.

// PatternMatch: exercise findPortsMatching with wildcard
TEST_F(ConcreteNetworkLinkedTest, FindPortsMatchingWildcard) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  PatternMatch pattern("?");
  PortSeq ports = network_.findPortsMatching(inv_cell, &pattern);
  // "A" and "Y" both match "?"
  EXPECT_EQ(ports.size(), 2u);
}

// ConcreteNetwork: findCellsMatching with no match
TEST_F(ConcreteNetworkLinkedTest, FindCellsMatchingNoMatch) {
  PatternMatch pattern("ZZZZ*");
  CellSeq cells = network_.findCellsMatching(lib_, &pattern);
  EXPECT_EQ(cells.size(), 0u);
}

// Network: isInsideNet with non-top instance
TEST_F(ConcreteNetworkLinkedTest, IsInsideNetNonTop) {
  // net1_ is in top, not inside u1_
  EXPECT_FALSE(network_.isInside(net1_, u1_));
}

// ConcreteNetwork: multiple connect/disconnect cycles
TEST_F(ConcreteNetworkLinkedTest, ConnectDisconnectCycle) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u11 = network_.makeInstance(inv_cell, "u11_cycle", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net = network_.makeNet("r6_cycle_net", network_.topInstance());

  // Connect
  Pin *pin = network_.connect(u11, port_a, net);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(network_.net(pin), net);

  // Disconnect
  network_.disconnectPin(pin);
  EXPECT_EQ(network_.net(pin), nullptr);

  // Reconnect to different net
  Net *net2 = network_.makeNet("r6_cycle_net2", network_.topInstance());
  Pin *pin2 = network_.connect(u11, port_a, net2);
  EXPECT_NE(pin2, nullptr);
  EXPECT_EQ(network_.net(pin2), net2);
}

// ConcreteBindingTbl: only exercised through linkReaderNetwork which
// is complex. Skip direct testing.

// SdcNetwork: findChild forwarding with non-existent
TEST_F(NetworkAdapterTest, SdcFindChildNonexistent) {
  Instance *top = sdc_net_->topInstance();
  Instance *child = sdc_net_->findChild(top, "nonexistent");
  EXPECT_EQ(child, nullptr);
}

// SdcNetwork: findNet with non-existent
TEST_F(NetworkAdapterTest, SdcFindNetNonexistent) {
  Instance *top = sdc_net_->topInstance();
  Net *found = sdc_net_->findNet(top, "nonexistent");
  EXPECT_EQ(found, nullptr);
}

// SdcNetwork: findPin with non-existent path
TEST_F(NetworkAdapterTest, SdcFindPinNonexistent) {
  Pin *found = sdc_net_->findPin("nonexistent/X");
  EXPECT_EQ(found, nullptr);
}

// SdcNetwork: findInstance with non-existent path
TEST_F(NetworkAdapterTest, SdcFindInstanceNonexistent) {
  Instance *found = sdc_net_->findInstance("nonexistent_inst");
  EXPECT_EQ(found, nullptr);
}

// SdcNetwork: deleteNet forwarding
TEST_F(NetworkAdapterTest, SdcDeleteNet) {
  Instance *top = sdc_net_->topInstance();
  Net *n = sdc_net_->makeNet("r6_sdc_delnet", top);
  EXPECT_NE(n, nullptr);
  sdc_net_->deleteNet(n);
  Net *found = sdc_net_->findNet(top, "r6_sdc_delnet");
  EXPECT_EQ(found, nullptr);
}

// SdcNetwork: libertyCell on cell (no liberty cell)
TEST_F(NetworkAdapterTest, SdcLibertyCellFromCell) {
  LibertyCell *lc = sdc_net_->libertyCell(inv_cell_);
  EXPECT_EQ(lc, nullptr);
}

// SdcNetwork: libertyPort from port
TEST_F(NetworkAdapterTest, SdcLibertyPortFromPort) {
  LibertyPort *lp = sdc_net_->libertyPort(port_a_);
  EXPECT_EQ(lp, nullptr);
}

////////////////////////////////////////////////////////////////
// R7_ tests for additional network coverage
////////////////////////////////////////////////////////////////

// ConcreteInstance::findChild on instance with no children
TEST_F(ConcreteNetworkLinkedTest, FindChildNonexistent) {
  // u1_ is a leaf instance, should have no children
  Instance *child = network_.findChild(u1_, "nonexistent");
  EXPECT_EQ(child, nullptr);
}

// ConcreteInstance::findPin(Port) - exercise via Network::findPin(Instance*, Port*)
TEST_F(ConcreteNetworkLinkedTest, FindPinByPort3) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.findPin(u1_, port_a);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(pin, pin_u1_a_);
}

// ConcretePin::name() - exercises the name() method on concrete pins
TEST_F(ConcreteNetworkLinkedTest, PinName2) {
  const char *name = network_.name(network_.port(pin_u1_a_));
  EXPECT_NE(name, nullptr);
  EXPECT_STREQ(name, "A");
}

// ConcretePin::setVertexId - exercises via Network::setVertexId
TEST_F(ConcreteNetworkLinkedTest, PinVertexId2) {
  VertexId orig = network_.vertexId(pin_u1_a_);
  network_.setVertexId(pin_u1_a_, 42);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 42u);
  // Restore
  network_.setVertexId(pin_u1_a_, orig);
}

// ConcreteNet: term iterator (exercises ConcreteNetTermIterator)
TEST_F(ConcreteNetworkLinkedTest, NetTermIterator2) {
  NetTermIterator *iter = network_.termIterator(net1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // net1_ has pins from leaf instances, which don't have terms
  EXPECT_GE(count, 0);
}

// ConcreteNet: pin iterator (exercises ConcreteNetPinIterator)
TEST_F(ConcreteNetworkLinkedTest, NetPinIterator2) {
  NetPinIterator *iter = network_.pinIterator(net2_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // net2_ connects u1_/Y and u2_/A
  EXPECT_EQ(count, 2);
}

// Network::makeTerm (exercises ConcreteTerm constructor and ConcreteNet::addTerm)
TEST_F(ConcreteNetworkLinkedTest, MakeTermAndTermName) {
  // Make a top-level pin to create a term
  Instance *top = network_.topInstance();
  Cell *top_cell = network_.cell(top);
  Port *clk_port = network_.findPort(top_cell, "clk");
  Net *term_net = network_.makeNet("r7_term_net", top);
  Pin *top_pin = network_.connect(top, clk_port, term_net);
  EXPECT_NE(top_pin, nullptr);
  // Top-level pins should have terms
  Term *term = network_.term(top_pin);
  if (term) {
    // Exercises ConcreteTerm::name()
    // Exercise Term accessors
    Net *tnet_check = network_.net(term);
    // Exercises NetworkNameAdapter::id(Term)
    ObjectId tid = network_.id(term);
    EXPECT_GE(tid, 0u);
    // Term net should be the net we connected to
    Net *tnet = network_.net(term);
    EXPECT_EQ(tnet, term_net);
    // Term pin should be the pin
    Pin *tpin = network_.pin(term);
    EXPECT_EQ(tpin, top_pin);
  }
}

// Network::findPinLinear - exercises the linear search fallback
TEST_F(ConcreteNetworkLinkedTest, FindPinLinear) {
  // findPinLinear is a fallback used when there's no hash lookup
  Pin *pin = network_.findPin(u1_, "A");
  EXPECT_NE(pin, nullptr);
  // Non-existent port
  Pin *no_pin = network_.findPin(u1_, "nonexistent");
  EXPECT_EQ(no_pin, nullptr);
}

// Network::findNetLinear - exercises linear net search
TEST_F(ConcreteNetworkLinkedTest, FindNetLinear) {
  Instance *top = network_.topInstance();
  Net *net = network_.findNet(top, "n1");
  EXPECT_NE(net, nullptr);
  Net *no_net = network_.findNet(top, "nonexistent_net");
  EXPECT_EQ(no_net, nullptr);
}

// Network::hasMembers on scalar port and bus port
TEST(ConcretePortTest, HasMembersScalar) {
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R7_HAS", true, "");
  ConcretePort *scalar = cell->makePort("A");
  EXPECT_FALSE(scalar->hasMembers());
  ConcretePort *bus = cell->makeBusPort("D", 1, 0);
  EXPECT_TRUE(bus->hasMembers());
}

// R7_LibertyLibraryFromInstance removed (segfault)

// R7_LibertyLibraryFromCell removed (segfault)

// ConcreteInstance::initPins - exercised when making a new instance
TEST_F(ConcreteNetworkLinkedTest, InitPinsNewInstance) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *new_inst = network_.makeInstance(inv_cell, "r7_initpins", network_.topInstance());
  EXPECT_NE(new_inst, nullptr);
  // After making instance, pins should be initialized
  network_.makePins(new_inst);
  // Should be able to find pins
  InstancePinIterator *iter = network_.pinIterator(new_inst);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // INV has 2 ports: A, Y
  EXPECT_EQ(count, 2);
}

// ConcreteNetwork::deleteInstance (exercises deleteChild, deletePin)
TEST_F(ConcreteNetworkLinkedTest, DeleteInstance2) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *del_inst = network_.makeInstance(inv_cell, "r7_del", network_.topInstance());
  EXPECT_NE(del_inst, nullptr);
  Instance *found = network_.findChild(network_.topInstance(), "r7_del");
  EXPECT_NE(found, nullptr);
  network_.deleteInstance(del_inst);
  Instance *gone = network_.findChild(network_.topInstance(), "r7_del");
  EXPECT_EQ(gone, nullptr);
}

// ConcreteNetwork: deleteNet (exercises ConcreteNet destructor, ConcreteInstance::deleteNet)
TEST_F(ConcreteNetworkLinkedTest, DeleteNet2) {
  Instance *top = network_.topInstance();
  Net *del_net = network_.makeNet("r7_del_net", top);
  EXPECT_NE(del_net, nullptr);
  Net *found = network_.findNet(top, "r7_del_net");
  EXPECT_NE(found, nullptr);
  network_.deleteNet(del_net);
  Net *gone = network_.findNet(top, "r7_del_net");
  EXPECT_EQ(gone, nullptr);
}

// ConcreteInstance::setCell (indirect via replaceCell)
TEST_F(ConcreteNetworkLinkedTest, ReplaceCell2) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  // Create a second cell type
  Cell *buf_cell = network_.makeCell(lib_, "R7_BUF", true, "test.lib");
  network_.makePort(buf_cell, "A");
  network_.makePort(buf_cell, "Y");
  Instance *inst = network_.makeInstance(inv_cell, "r7_replace", network_.topInstance());
  EXPECT_STREQ(network_.name(network_.cell(inst)), "INV");
  network_.replaceCell(inst, buf_cell);
  EXPECT_STREQ(network_.name(network_.cell(inst)), "R7_BUF");
}

// ConcreteInstance::addNet via makeNet and findNet on child instance
TEST_F(ConcreteNetworkLinkedTest, InstanceNet) {
  // Make net on a non-top instance (exercises ConcreteInstance::addNet(name, net))
  Cell *sub_cell = network_.makeCell(lib_, "R7_SUB", false, "test.lib");
  network_.makePort(sub_cell, "in1");
  Instance *sub = network_.makeInstance(sub_cell, "r7_sub", network_.topInstance());
  Net *sub_net = network_.makeNet("r7_sub_net", sub);
  EXPECT_NE(sub_net, nullptr);
  Net *found = network_.findNet(sub, "r7_sub_net");
  EXPECT_EQ(found, sub_net);
}

// NetworkNameAdapter: findPort forwarding
TEST_F(NetworkAdapterTest, AdapterFindPort2) {
  Port *port = sdc_net_->findPort(inv_cell_, "A");
  EXPECT_NE(port, nullptr);
  EXPECT_EQ(port, port_a_);
}

// NetworkNameAdapter: findPortsMatching forwarding
TEST_F(NetworkAdapterTest, AdapterFindPortsMatching2) {
  PatternMatch pattern("*");
  PortSeq ports = sdc_net_->findPortsMatching(inv_cell_, &pattern);
  EXPECT_GE(ports.size(), 2u);
}

// NetworkNameAdapter: name(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortName2) {
  const char *name = sdc_net_->name(port_a_);
  EXPECT_NE(name, nullptr);
  EXPECT_STREQ(name, "A");
}

// NetworkNameAdapter: busName(Port) forwarding
TEST_F(NetworkAdapterTest, AdapterPortBusName2) {
  const char *bname = sdc_net_->busName(port_a_);
  EXPECT_NE(bname, nullptr);
}

// R7_AdapterFindBusBit removed (segfault)

// R7_AdapterFindMember removed (segfault)

// R7_AdapterFindPinLibertyPort removed (segfault)

// NetworkNameAdapter: id(Term) forwarding
TEST_F(NetworkAdapterTest, AdapterTermId) {
  // Make a top-level pin to get a term
  Instance *top = sdc_net_->topInstance();
  Cell *top_cell = sdc_net_->cell(top);
  Port *in1 = sdc_net_->findPort(top_cell, "in1");
  Net *tnet = sdc_net_->makeNet("r7_term_net2", top);
  Pin *tpin = sdc_net_->connect(top, in1, tnet);
  EXPECT_NE(tpin, nullptr);
  Term *term = sdc_net_->term(tpin);
  if (term) {
    ObjectId tid = sdc_net_->id(term);
    EXPECT_GE(tid, 0u);
  }
}

// NetworkNameAdapter: makeNet forwarding
TEST_F(NetworkAdapterTest, AdapterMakeNet2) {
  Instance *top = sdc_net_->topInstance();
  Net *net = sdc_net_->makeNet("r7_adapter_net", top);
  EXPECT_NE(net, nullptr);
}

// NetworkNameAdapter: connect(Instance, Port, Net) forwarding
TEST_F(NetworkAdapterTest, AdapterConnect2) {
  Instance *top = sdc_net_->topInstance();
  Net *net = sdc_net_->makeNet("r7_adapter_conn_net", top);
  // makeInstance requires LibertyCell, get it from the network
  LibertyCell *lib_cell = sdc_net_->findLibertyCell("INV_X1");
  if (lib_cell) {
    Instance *inst = sdc_net_->makeInstance(lib_cell, "r7_adapter_inst", top);
    EXPECT_NE(inst, nullptr);
  }
}

// Network::findNetsMatchingLinear exercises
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatchingLinear) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("n*");
  NetSeq matches = network_.findNetsMatching(top, &pattern);
  // Should match n1, n2, n3
  EXPECT_GE(matches.size(), 3u);
}

// ConcreteNetwork: addConstantNet and clearConstantNets
TEST_F(ConcreteNetworkLinkedTest, ConstantNets) {
  Instance *top = network_.topInstance();
  Net *const_net = network_.makeNet("r7_const", top);
  network_.addConstantNet(const_net, LogicValue::one);
  // constantPinIterator should work
  ConstantPinIterator *iter = network_.constantPinIterator();
  ASSERT_NE(iter, nullptr);
  delete iter;
  // Clear exercises clearConstantNets
  network_.clear();
}

// ConcreteLibertyLibraryIterator exercise
TEST(ConcreteNetworkTest, LibertyLibraryIterator) {
  ConcreteNetwork network;
  LibertyLibraryIterator *iter = network.libertyLibraryIterator();
  ASSERT_NE(iter, nullptr);
  EXPECT_FALSE(iter->hasNext());
  delete iter;
}

// ConcreteLibraryIterator1 exercise
TEST(ConcreteNetworkTest, LibraryIteratorEmpty) {
  ConcreteNetwork network;
  LibraryIterator *iter = network.libraryIterator();
  ASSERT_NE(iter, nullptr);
  EXPECT_FALSE(iter->hasNext());
  delete iter;
}

// ConcreteInstancePinIterator exercise
TEST_F(ConcreteNetworkLinkedTest, InstancePinIterator2) {
  InstancePinIterator *iter = network_.pinIterator(u1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Pin *pin = iter->next();
    EXPECT_NE(pin, nullptr);
    count++;
  }
  delete iter;
  // INV has 2 pins: A and Y
  EXPECT_EQ(count, 2);
}

// Network: mergeInto exercises (ConcreteNet::mergeInto path)
TEST_F(ConcreteNetworkLinkedTest, MergeNets) {
  Instance *top = network_.topInstance();
  Net *na = network_.makeNet("r7_merge_a", top);
  Net *nb = network_.makeNet("r7_merge_b", top);
  network_.mergeInto(na, nb);
  Net *merged = network_.mergedInto(na);
  EXPECT_EQ(merged, nb);
}

// BusPort: setDirection exercises BusPort::setDirection
TEST(ConcretePortTest, BusPortSetDirectionInput) {
  PortDirection::init();
  ConcreteLibrary lib("test_lib", "test.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("R7_BDIR", true, "");
  ConcretePort *bus = cell->makeBusPort("IN", 3, 0);
  bus->setDirection(PortDirection::input());
  EXPECT_EQ(bus->direction(), PortDirection::input());
  // Verify bits got the direction too
  for (int i = 0; i <= 3; i++) {
    ConcretePort *bit = bus->findBusBit(i);
    if (bit) {
      EXPECT_EQ(bit->direction(), PortDirection::input());
    }
  }
}

// R7_CheckLibertyCorners removed (segfault)

// R7_AdapterLinkNetwork removed (segfault)

// ConcreteNetwork: findAnyCell
TEST_F(ConcreteNetworkLinkedTest, FindAnyCell) {
  Cell *cell = network_.findAnyCell("INV");
  EXPECT_NE(cell, nullptr);
  Cell *no_cell = network_.findAnyCell("NONEXISTENT_R7");
  EXPECT_EQ(no_cell, nullptr);
}

// ConcreteNetwork: isPower/isGround on net
TEST_F(ConcreteNetworkLinkedTest, NetPowerGround) {
  EXPECT_FALSE(network_.isPower(net1_));
  EXPECT_FALSE(network_.isGround(net1_));
}

// ConcreteNetwork: net instance
TEST_F(ConcreteNetworkLinkedTest, NetInstance2) {
  Instance *inst = network_.instance(net1_);
  EXPECT_EQ(inst, network_.topInstance());
}

// Network: cellName convenience
TEST_F(ConcreteNetworkLinkedTest, CellNameConvenience) {
  const char *name = network_.cellName(u2_);
  EXPECT_STREQ(name, "INV");
}

// ConcreteNetwork: pin direction
TEST_F(ConcreteNetworkLinkedTest, PinDirection2) {
  PortDirection *dir = network_.direction(pin_u1_a_);
  EXPECT_NE(dir, nullptr);
  EXPECT_TRUE(dir->isInput());
}

// NetworkNameAdapter: hasMembers on scalar port
TEST_F(NetworkAdapterTest, AdapterHasMembers) {
  bool has = sdc_net_->hasMembers(port_a_);
  EXPECT_FALSE(has);
}

// ConcreteNetwork: disconnectPin and reconnect cycle
TEST_F(ConcreteNetworkLinkedTest, DisconnectReconnect) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *inst = network_.makeInstance(inv_cell, "r7_disc", network_.topInstance());
  Port *port_a = network_.findPort(inv_cell, "A");
  Net *net_a = network_.makeNet("r7_disc_net", network_.topInstance());
  Pin *pin = network_.connect(inst, port_a, net_a);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(network_.net(pin), net_a);
  network_.disconnectPin(pin);
  EXPECT_EQ(network_.net(pin), nullptr);
  // Reconnect
  Net *net_b = network_.makeNet("r7_disc_net2", network_.topInstance());
  Pin *pin2 = network_.connect(inst, port_a, net_b);
  EXPECT_NE(pin2, nullptr);
  EXPECT_EQ(network_.net(pin2), net_b);
}

// ConcreteNetwork: instance attribute
TEST_F(ConcreteNetworkLinkedTest, InstanceAttribute) {
  network_.setAttribute(u1_, "r7_key", "r7_value");
  std::string val = network_.getAttribute(u1_, "r7_key");
  EXPECT_EQ(val, "r7_value");
  std::string no_val = network_.getAttribute(u1_, "nonexistent_r7");
  EXPECT_TRUE(no_val.empty());
}

// ConcreteNetwork: instance net iterator
TEST_F(ConcreteNetworkLinkedTest, InstanceNetIterator2) {
  // Net iterator on a child instance with local nets
  Cell *sub_cell = network_.makeCell(lib_, "R7_SUBC", false, "test.lib");
  network_.makePort(sub_cell, "p1");
  Instance *sub = network_.makeInstance(sub_cell, "r7_neti", network_.topInstance());
  Net *local_net = network_.makeNet("r7_local", sub);
  EXPECT_NE(local_net, nullptr);
  InstanceNetIterator *iter = network_.netIterator(sub);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// Network: visitConnectedPins exercises (through connectedPins API)
TEST_F(ConcreteNetworkLinkedTest, ConnectedPins) {
  // Exercise connectedPinIterator as an alternative
  ConnectedPinIterator *iter = network_.connectedPinIterator(pin_u1_a_);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// ConcreteNetwork: portBitCount
TEST_F(ConcreteNetworkLinkedTest, PortBitCount) {
  Cell *cell = network_.cell(u1_);
  int count = network_.portBitCount(cell);
  // INV has A and Y = 2 bit ports
  EXPECT_EQ(count, 2);
}

// ConcreteNetwork: setCellNetworkView / cellNetworkView
TEST_F(ConcreteNetworkLinkedTest, CellNetworkView) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  // Initially null
  Instance *view = network_.cellNetworkView(inv_cell);
  EXPECT_EQ(view, nullptr);
  // Set and get
  network_.setCellNetworkView(inv_cell, u1_);
  view = network_.cellNetworkView(inv_cell);
  EXPECT_EQ(view, u1_);
  // Delete all views
  network_.deleteCellNetworkViews();
  view = network_.cellNetworkView(inv_cell);
  EXPECT_EQ(view, nullptr);
}

// R7_AdapterMakeInstanceLiberty removed (segfault)

////////////////////////////////////////////////////////////////
// R8_ tests for additional network coverage
////////////////////////////////////////////////////////////////

// ConcreteNetwork::connect(Instance*, LibertyPort*, Net*) - uncovered overload
TEST_F(ConcreteNetworkLinkedTest, ConnectWithLibertyPort) {
  // connect with LibertyPort* just forwards to connect with Port*
  // Since we don't have a real LibertyPort, test the Port-based connect path
  Instance *top = network_.topInstance();
  Net *extra_net = network_.makeNet("extra_n", top);
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u3 = network_.makeInstance(inv_cell, "u3", top);
  Port *inv_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.connect(u3, inv_a, extra_net);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(network_.net(pin), extra_net);
  // Clean up
  network_.disconnectPin(pin);
  network_.deleteInstance(u3);
  network_.deleteNet(extra_net);
}

// ConcreteNetwork::clearConstantNets
TEST_F(ConcreteNetworkLinkedTest, ClearConstantNets) {
  // Add constant nets and clear them
  network_.addConstantNet(net1_, LogicValue::zero);
  network_.addConstantNet(net2_, LogicValue::one);
  // Iterate to verify they exist
  ConstantPinIterator *iter = network_.constantPinIterator();
  EXPECT_NE(iter, nullptr);
  delete iter;
  // clearConstantNets is called implicitly by clear()
  // We can't call it directly since it's protected, but we can verify
  // the constant nets are accessible via the non-null iterator above
}

// ConcreteInstance::cell() const - uncovered
TEST_F(ConcreteNetworkLinkedTest, InstanceCell2) {
  Cell *cell = network_.cell(u1_);
  EXPECT_NE(cell, nullptr);
  // Verify it's the INV cell
  EXPECT_STREQ(network_.name(cell), "INV");
}

// ConcreteInstance::findChild - exercise child lookup
TEST_F(ConcreteNetworkLinkedTest, FindChildInstance) {
  Instance *top = network_.topInstance();
  Instance *child = network_.findChild(top, "u1");
  EXPECT_EQ(child, u1_);
  Instance *no_child = network_.findChild(top, "nonexistent_child");
  EXPECT_EQ(no_child, nullptr);
}

// ConcreteInstance::findPin(Port*) - uncovered overload
TEST_F(ConcreteNetworkLinkedTest, FindPinByPortDirect2) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.findPin(u1_, port_a);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(pin, pin_u1_a_);
}

// ConcreteInstance::deleteChild - exercise child deletion
TEST_F(ConcreteNetworkLinkedTest, DeleteChildInstance) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *temp = network_.makeInstance(inv_cell, "temp_child", top);
  EXPECT_NE(temp, nullptr);
  Instance *found = network_.findChild(top, "temp_child");
  EXPECT_EQ(found, temp);
  network_.deleteInstance(temp);
  found = network_.findChild(top, "temp_child");
  EXPECT_EQ(found, nullptr);
}

// ConcreteInstance::addNet / deleteNet through ConcreteNetwork
TEST_F(ConcreteNetworkLinkedTest, AddDeleteNet) {
  Instance *top = network_.topInstance();
  Net *new_net = network_.makeNet("test_net_r8", top);
  EXPECT_NE(new_net, nullptr);
  Net *found = network_.findNet(top, "test_net_r8");
  EXPECT_EQ(found, new_net);
  network_.deleteNet(new_net);
  found = network_.findNet(top, "test_net_r8");
  EXPECT_EQ(found, nullptr);
}

// ConcreteInstance::setCell
TEST_F(ConcreteNetworkLinkedTest, SetInstanceCell) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  // Replace u1 cell with same cell (exercises the path)
  network_.replaceCell(u1_, inv_cell);
  Cell *cell = network_.cell(u1_);
  EXPECT_EQ(cell, inv_cell);
}

// ConcreteInstance::initPins - exercise pin initialization
TEST_F(ConcreteNetworkLinkedTest, InstanceInitPins) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u_new = network_.makeInstance(inv_cell, "u_init", top);
  // makePins exercises initPins internally
  network_.makePins(u_new);
  // Verify we can iterate pins
  InstancePinIterator *iter = network_.pinIterator(u_new);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2); // INV has A and Y
  network_.deleteInstance(u_new);
}

// ConcretePin: port and instance accessors
TEST_F(ConcreteNetworkLinkedTest, PinPortAndInstance) {
  Port *port = network_.port(pin_u1_a_);
  EXPECT_NE(port, nullptr);
  Instance *inst = network_.instance(pin_u1_a_);
  EXPECT_EQ(inst, u1_);
}

// ConcretePin::setVertexId - uncovered
TEST_F(ConcreteNetworkLinkedTest, PinSetVertexId) {
  VertexId orig = network_.vertexId(pin_u1_a_);
  network_.setVertexId(pin_u1_a_, 999);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 999u);
  network_.setVertexId(pin_u1_a_, orig);
}

// ConcreteNet::addPin / deletePin (through connect/disconnect)
TEST_F(ConcreteNetworkLinkedTest, NetPinManipulation) {
  Instance *top = network_.topInstance();
  Net *test_net = network_.makeNet("r8_net", top);
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u_temp = network_.makeInstance(inv_cell, "u_r8", top);
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.connect(u_temp, port_a, test_net);
  EXPECT_NE(pin, nullptr);

  // Verify pin is on net
  NetPinIterator *iter = network_.pinIterator(test_net);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 1);

  // Disconnect and verify
  network_.disconnectPin(pin);
  iter = network_.pinIterator(test_net);
  count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 0);

  network_.deleteInstance(u_temp);
  network_.deleteNet(test_net);
}

// ConcreteNet::addTerm / deleteTerm (through makeTerm)
TEST_F(ConcreteNetworkLinkedTest, TermManipulation) {
  Instance *top = network_.topInstance();
  Cell *top_cell = network_.cell(top);
  Port *clk_port = network_.findPort(top_cell, "clk");
  Net *clk_net = network_.makeNet("clk_net_r8", top);

  // Connect top-level port pin to net
  Pin *top_pin = network_.connect(top, clk_port, clk_net);
  EXPECT_NE(top_pin, nullptr);

  // Make a term for the pin
  Term *term = network_.makeTerm(top_pin, clk_net);
  EXPECT_NE(term, nullptr);

  // Get term's pin and net
  Pin *term_pin = network_.pin(term);
  EXPECT_EQ(term_pin, top_pin);
  Net *term_net = network_.net(term);
  EXPECT_EQ(term_net, clk_net);

  // Term name
  ObjectId tid = network_.id(term);
  EXPECT_GT(tid, 0u);

  // Verify term iterator on net
  NetTermIterator *titer = network_.termIterator(clk_net);
  int tcount = 0;
  while (titer->hasNext()) {
    titer->next();
    tcount++;
  }
  delete titer;
  EXPECT_GE(tcount, 1);

  network_.disconnectPin(top_pin);
  network_.deleteNet(clk_net);
}

// ConcreteNetPinIterator - uncovered constructor
TEST_F(ConcreteNetworkLinkedTest, NetPinIteratorEmpty) {
  Instance *top = network_.topInstance();
  Net *empty_net = network_.makeNet("empty_r8", top);
  NetPinIterator *iter = network_.pinIterator(empty_net);
  EXPECT_NE(iter, nullptr);
  EXPECT_FALSE(iter->hasNext());
  delete iter;
  network_.deleteNet(empty_net);
}

// ConcreteNetTermIterator - uncovered constructor
TEST_F(ConcreteNetworkLinkedTest, NetTermIteratorEmpty2) {
  Instance *top = network_.topInstance();
  Net *empty_net = network_.makeNet("empty_term_r8", top);
  NetTermIterator *iter = network_.termIterator(empty_net);
  EXPECT_NE(iter, nullptr);
  EXPECT_FALSE(iter->hasNext());
  delete iter;
  network_.deleteNet(empty_net);
}

// ConcreteLibraryIterator1 - uncovered
TEST_F(ConcreteNetworkLinkedTest, LibraryIterator) {
  LibraryIterator *iter = network_.libraryIterator();
  int count = 0;
  while (iter->hasNext()) {
    Library *lib = iter->next();
    EXPECT_NE(lib, nullptr);
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

// ConcreteLibertyLibraryIterator - uncovered
TEST_F(ConcreteNetworkLinkedTest, LibertyLibraryIterator) {
  LibertyLibraryIterator *iter = network_.libertyLibraryIterator();
  EXPECT_NE(iter, nullptr);
  // No liberty libraries in our simple network, so it may be empty
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // Count can be 0 - just verifying iteration completes
  EXPECT_GE(count, 0);
}

// ConcreteCellPortIterator1 - uncovered
TEST_F(ConcreteNetworkLinkedTest, CellPortIterator) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  CellPortIterator *iter = network_.portIterator(inv_cell);
  int count = 0;
  while (iter->hasNext()) {
    Port *p = iter->next();
    EXPECT_NE(p, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2); // A and Y
}

// ConcreteCellPortBitIterator / ConcreteCellPortBitIterator1 - uncovered
TEST_F(ConcreteNetworkLinkedTest, CellPortBitIterator2) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  CellPortBitIterator *iter = network_.portBitIterator(inv_cell);
  int count = 0;
  while (iter->hasNext()) {
    Port *p = iter->next();
    EXPECT_NE(p, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2); // A and Y (scalar ports)
}

// ConcreteInstanceChildIterator - uncovered
TEST_F(ConcreteNetworkLinkedTest, InstanceChildIterator) {
  Instance *top = network_.topInstance();
  InstanceChildIterator *iter = network_.childIterator(top);
  int count = 0;
  while (iter->hasNext()) {
    Instance *child = iter->next();
    EXPECT_NE(child, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2); // u1 and u2
}

// ConcreteInstancePinIterator - uncovered constructor
TEST_F(ConcreteNetworkLinkedTest, InstancePinIteratorCount) {
  InstancePinIterator *iter = network_.pinIterator(u1_);
  int count = 0;
  while (iter->hasNext()) {
    Pin *p = iter->next();
    EXPECT_NE(p, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2); // A and Y connected
}

// R8_LibertyLibraryOfInstance removed (segfault - no liberty in simple network)
// R8_LibertyLibraryOfCell removed (segfault - no liberty in simple network)

// Network::hasMembers - uncovered
TEST_F(ConcreteNetworkLinkedTest, HasMembers) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  bool has = network_.hasMembers(port_a);
  EXPECT_FALSE(has); // scalar port
}

// Network::findPin with port name string
TEST_F(ConcreteNetworkLinkedTest, FindPinByName2) {
  Pin *pin = network_.findPin(u1_, "A");
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(pin, pin_u1_a_);
  Pin *no_pin = network_.findPin(u1_, "nonexistent");
  EXPECT_EQ(no_pin, nullptr);
}

// Network::findPin(Instance*, Port*) - uncovered overload
TEST_F(ConcreteNetworkLinkedTest, FindPinByPortOverload) {
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.findPin(u1_, port_a);
  EXPECT_NE(pin, nullptr);
  EXPECT_EQ(pin, pin_u1_a_);
}

// Network::findNet by name
TEST_F(ConcreteNetworkLinkedTest, FindNetByName2) {
  Instance *top = network_.topInstance();
  Net *net = network_.findNet(top, "n1");
  EXPECT_NE(net, nullptr);
  EXPECT_EQ(net, net1_);
  Net *no_net = network_.findNet(top, "nonexistent_net");
  EXPECT_EQ(no_net, nullptr);
}

// Network::findNetsMatching pattern
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatching2) {
  Instance *top = network_.topInstance();
  PatternMatch pat("n*", false, false, nullptr);
  NetSeq matches;
  network_.findInstNetsMatching(top, &pat, matches);
  EXPECT_GE(matches.size(), 3u); // n1, n2, n3
}

// ConcreteNetwork::mergeNets exercise
TEST_F(ConcreteNetworkLinkedTest, MergeNetsExercise) {
  Instance *top = network_.topInstance();
  Net *a = network_.makeNet("merge_a", top);
  Net *b = network_.makeNet("merge_b", top);
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u_merge = network_.makeInstance(inv_cell, "u_merge", top);
  Port *port_a = network_.findPort(inv_cell, "A");
  Port *port_y = network_.findPort(inv_cell, "Y");
  Pin *p1 = network_.connect(u_merge, port_a, a);
  Pin *p2 = network_.connect(u_merge, port_y, b);
  EXPECT_NE(p1, nullptr);
  EXPECT_NE(p2, nullptr);

  // Merge a into b
  network_.mergeInto(a, b);
  Net *merged = network_.mergedInto(a);
  EXPECT_EQ(merged, b);

  network_.deleteInstance(u_merge);
  network_.deleteNet(b);
}

// NetworkNameAdapter forwarding tests via SdcNetwork
// NetworkNameAdapter::findPort
TEST_F(NetworkAdapterTest, AdapterFindPortByName) {
  Port *port = sdc_net_->findPort(inv_cell_, "A");
  EXPECT_NE(port, nullptr);
  EXPECT_EQ(port, port_a_);
  Port *no_port = sdc_net_->findPort(inv_cell_, "nonexistent");
  EXPECT_EQ(no_port, nullptr);
}

// NetworkNameAdapter::findPortsMatching
TEST_F(NetworkAdapterTest, AdapterFindPortsMatching3) {
  PatternMatch pat("*", false, false, nullptr);
  PortSeq ports = sdc_net_->findPortsMatching(inv_cell_, &pat);
  EXPECT_EQ(ports.size(), 2u); // A and Y
}

// NetworkNameAdapter::name(Port*) forwarding
TEST_F(NetworkAdapterTest, AdapterPortNameForward) {
  const char *name = sdc_net_->name(port_a_);
  EXPECT_STREQ(name, "A");
}

// NetworkNameAdapter::busName(Port*) forwarding
TEST_F(NetworkAdapterTest, AdapterBusNameForward) {
  const char *bname = sdc_net_->busName(port_a_);
  EXPECT_STREQ(bname, "A"); // scalar port
}

// R8_AdapterFindBusBit removed (segfault)
// R8_AdapterFindMember removed (segfault)
// R8_AdapterFindPinLibertyPort removed (segfault)
// R8_AdapterLinkNetwork removed (segfault)
// R8_AdapterMakeInstanceNull removed (segfault)

// NetworkNameAdapter::makeNet forwarding
TEST_F(NetworkAdapterTest, AdapterMakeNetForward) {
  Instance *top = sdc_net_->topInstance();
  Net *net = sdc_net_->makeNet("adapter_net_r8", top);
  EXPECT_NE(net, nullptr);
  EXPECT_STREQ(network_.name(net), "adapter_net_r8");
  sdc_net_->deleteNet(net);
}

// NetworkNameAdapter::connect forwarding
TEST_F(NetworkAdapterTest, AdapterConnectForward) {
  Instance *top = sdc_net_->topInstance();
  Net *net = sdc_net_->makeNet("conn_r8", top);
  Port *port_y = network_.findPort(inv_cell_, "Y");
  Pin *pin = sdc_net_->connect(u1_, port_y, net);
  EXPECT_NE(pin, nullptr);
  sdc_net_->disconnectPin(pin);
  sdc_net_->deleteNet(net);
}

// NetworkEdit::connectPin exercises
TEST_F(ConcreteNetworkLinkedTest, DisconnectAndReconnect) {
  // Disconnect pin and reconnect to different net
  Instance *top = network_.topInstance();
  Net *alt_net = network_.makeNet("alt_r8", top);
  network_.disconnectPin(pin_u1_a_);
  EXPECT_EQ(network_.net(pin_u1_a_), nullptr);

  Cell *inv_cell = network_.findCell(lib_, "INV");
  Port *port_a = network_.findPort(inv_cell, "A");
  pin_u1_a_ = network_.connect(u1_, port_a, alt_net);
  EXPECT_NE(pin_u1_a_, nullptr);
  EXPECT_EQ(network_.net(pin_u1_a_), alt_net);

  // Reconnect to original
  network_.disconnectPin(pin_u1_a_);
  pin_u1_a_ = network_.connect(u1_, port_a, net1_);
  network_.deleteNet(alt_net);
}

// ConcretePortMemberIterator1 - uncovered
TEST(ConcretePortR8Test, PortMemberIteratorOnBus) {
  ConcreteLibrary lib("r8_lib", "r8.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("BUS_CELL", true, "");
  ConcretePort *bus = cell->makeBusPort("D", 7, 0);
  ConcretePortMemberIterator *iter = bus->memberIterator();
  int count = 0;
  while (iter->hasNext()) {
    ConcretePort *member = iter->next();
    EXPECT_NE(member, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 8);
}

// ConcretePortMemberIterator1 on scalar port - should have no members
TEST(ConcretePortR8Test, PortMemberIteratorOnScalar) {
  ConcreteLibrary lib("r8_lib2", "r8.lib", false);
  ConcreteCell *cell = lib.makeCell("SCALAR_CELL", true, "");
  ConcretePort *port = cell->makePort("A");
  ConcretePortMemberIterator *iter = port->memberIterator();
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 0);
}

// BusPort::setDirection - uncovered
TEST(ConcretePortR8Test, BusPortSetDirection) {
  if (PortDirection::input() == nullptr)
    PortDirection::init();
  ConcreteLibrary lib("r8_lib3", "r8.lib", false);
  lib.setBusBrkts('[', ']');
  ConcreteCell *cell = lib.makeCell("DIR_CELL", true, "");
  ConcretePort *bus = cell->makeBusPort("Q", 3, 0);
  bus->setDirection(PortDirection::output());
  EXPECT_EQ(bus->direction(), PortDirection::output());
  // Check propagation to bits
  ConcretePort *bit0 = bus->findBusBit(0);
  EXPECT_NE(bit0, nullptr);
  EXPECT_EQ(bit0->direction(), PortDirection::output());
}

// ConcreteNetwork: multiple nets and find
TEST_F(ConcreteNetworkLinkedTest, MultipleNetsFind) {
  Instance *top = network_.topInstance();
  for (int i = 0; i < 10; i++) {
    std::string name = "multi_net_" + std::to_string(i);
    Net *n = network_.makeNet(name.c_str(), top);
    EXPECT_NE(n, nullptr);
  }
  for (int i = 0; i < 10; i++) {
    std::string name = "multi_net_" + std::to_string(i);
    Net *found = network_.findNet(top, name.c_str());
    EXPECT_NE(found, nullptr);
  }
  // Clean up
  for (int i = 0; i < 10; i++) {
    std::string name = "multi_net_" + std::to_string(i);
    Net *n = network_.findNet(top, name.c_str());
    if (n)
      network_.deleteNet(n);
  }
}

// ConcreteNetwork: instance with many children
TEST_F(ConcreteNetworkLinkedTest, ManyChildren) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.findCell(lib_, "INV");
  for (int i = 0; i < 5; i++) {
    std::string name = "child_r8_" + std::to_string(i);
    Instance *child = network_.makeInstance(inv_cell, name.c_str(), top);
    EXPECT_NE(child, nullptr);
  }
  InstanceChildIterator *iter = network_.childIterator(top);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 7); // u1, u2, + 5 new
  // Clean up
  for (int i = 0; i < 5; i++) {
    std::string name = "child_r8_" + std::to_string(i);
    Instance *child = network_.findChild(top, name.c_str());
    if (child)
      network_.deleteInstance(child);
  }
}

// ConcreteNetwork: deletePin through disconnect
TEST_F(ConcreteNetworkLinkedTest, DeletePinPath) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.findCell(lib_, "INV");
  Instance *u_del = network_.makeInstance(inv_cell, "u_del_r8", top);
  Net *del_net = network_.makeNet("del_net_r8", top);
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *pin = network_.connect(u_del, port_a, del_net);
  EXPECT_NE(pin, nullptr);

  // Disconnect exercises deletePin path
  network_.disconnectPin(pin);
  Pin *found = network_.findPin(u_del, "A");
  // After disconnect, pin should still exist but not connected
  EXPECT_EQ(network_.net(found), nullptr);

  network_.deleteInstance(u_del);
  network_.deleteNet(del_net);
}

// R8_CheckLibertyCorners removed (segfault - no liberty in simple network)

// ConnectedPinIterator1 - uncovered through connectedPinIterator
TEST_F(ConcreteNetworkLinkedTest, ConnectedPinIteratorMultiPin) {
  // net2_ has u1_y and u2_a connected
  ConnectedPinIterator *iter = network_.connectedPinIterator(pin_u1_y_);
  int count = 0;
  while (iter->hasNext()) {
    const Pin *p = iter->next();
    EXPECT_NE(p, nullptr);
    count++;
  }
  delete iter;
  EXPECT_GE(count, 2); // At least u1_y and u2_a
}

// NetworkNameAdapter: various forwarding methods
TEST_F(NetworkAdapterTest, AdapterCellName2) {
  const char *name = sdc_net_->name(inv_cell_);
  EXPECT_STREQ(name, "BUF");
}

TEST_F(NetworkAdapterTest, AdapterCellId2) {
  ObjectId aid = sdc_net_->id(inv_cell_);
  ObjectId did = network_.id(inv_cell_);
  EXPECT_EQ(aid, did);
}

TEST_F(NetworkAdapterTest, AdapterCellLibrary2) {
  Library *lib = sdc_net_->library(inv_cell_);
  EXPECT_EQ(lib, lib_);
}

TEST_F(NetworkAdapterTest, AdapterCellIsLeaf2) {
  EXPECT_TRUE(sdc_net_->isLeaf(inv_cell_));
}

TEST_F(NetworkAdapterTest, AdapterInstanceId2) {
  ObjectId aid = sdc_net_->id(u1_);
  ObjectId did = network_.id(u1_);
  EXPECT_EQ(aid, did);
}

TEST_F(NetworkAdapterTest, AdapterInstanceCell2) {
  Cell *cell = sdc_net_->cell(u1_);
  EXPECT_EQ(cell, inv_cell_);
}

TEST_F(NetworkAdapterTest, AdapterInstanceParent2) {
  Instance *parent = sdc_net_->parent(u1_);
  EXPECT_EQ(parent, sdc_net_->topInstance());
}

TEST_F(NetworkAdapterTest, AdapterInstanceIsLeaf2) {
  EXPECT_TRUE(sdc_net_->isLeaf(u1_));
}

TEST_F(NetworkAdapterTest, AdapterPinId2) {
  ObjectId aid = sdc_net_->id(pin_b1_a_);
  ObjectId did = network_.id(pin_b1_a_);
  EXPECT_EQ(aid, did);
}

TEST_F(NetworkAdapterTest, AdapterPinPort2) {
  Port *port = sdc_net_->port(pin_b1_a_);
  EXPECT_EQ(port, port_a_);
}

TEST_F(NetworkAdapterTest, AdapterPinInstance2) {
  Instance *inst = sdc_net_->instance(pin_b1_a_);
  EXPECT_EQ(inst, u1_);
}

TEST_F(NetworkAdapterTest, AdapterPinNet2) {
  Net *net = sdc_net_->net(pin_b1_a_);
  EXPECT_EQ(net, net1_);
}

TEST_F(NetworkAdapterTest, AdapterPinDirection2) {
  PortDirection *dir = sdc_net_->direction(pin_b1_a_);
  EXPECT_TRUE(dir->isInput());
}

TEST_F(NetworkAdapterTest, AdapterPinVertexId2) {
  VertexId vid = sdc_net_->vertexId(pin_b1_a_);
  VertexId dvid = network_.vertexId(pin_b1_a_);
  EXPECT_EQ(vid, dvid);
}

TEST_F(NetworkAdapterTest, AdapterNetId2) {
  ObjectId aid = sdc_net_->id(net1_);
  ObjectId did = network_.id(net1_);
  EXPECT_EQ(aid, did);
}

TEST_F(NetworkAdapterTest, AdapterNetInstance2) {
  Instance *inst = sdc_net_->instance(net1_);
  EXPECT_EQ(inst, sdc_net_->topInstance());
}

TEST_F(NetworkAdapterTest, AdapterNetIsPower2) {
  EXPECT_FALSE(sdc_net_->isPower(net1_));
}

TEST_F(NetworkAdapterTest, AdapterNetIsGround2) {
  EXPECT_FALSE(sdc_net_->isGround(net1_));
}

TEST_F(NetworkAdapterTest, AdapterNetPinIterator2) {
  NetPinIterator *iter = sdc_net_->pinIterator(net1_);
  EXPECT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  EXPECT_GE(count, 1);
}

TEST_F(NetworkAdapterTest, AdapterNetTermIterator2) {
  NetTermIterator *iter = sdc_net_->termIterator(net1_);
  EXPECT_NE(iter, nullptr);
  delete iter;
}

////////////////////////////////////////////////////////////////
// R10_ tests for additional network coverage
////////////////////////////////////////////////////////////////

// R10_ ConcreteNetwork: Bus port creation and direction setting
// Covers: BusPort::BusPort, BusPort::setDirection
TEST_F(ConcreteNetworkLinkedTest, BusPortCreation) {
  // Create bus port on a new cell (not one with existing instances)
  Cell *bus_cell = network_.makeCell(lib_, "BUS_TEST", true, "test.lib");
  Port *bus = network_.makeBusPort(bus_cell, "bus_data", 0, 7);
  ASSERT_NE(bus, nullptr);
  EXPECT_TRUE(network_.isBus(bus));
  EXPECT_EQ(network_.size(bus), 8);
  network_.setDirection(bus, PortDirection::input());
  EXPECT_TRUE(network_.direction(bus)->isInput());
  // Check bus members
  EXPECT_TRUE(network_.hasMembers(bus));
  Port *bit0 = network_.findMember(bus, 0);
  EXPECT_NE(bit0, nullptr);
}

// R10_ ConcreteNetwork: multiple clear operations
// Covers: ConcreteNetwork clear paths
TEST_F(ConcreteNetworkLinkedTest, ClearAndRebuild) {
  // Verify we can query before clear
  Instance *top = network_.topInstance();
  EXPECT_NE(top, nullptr);
  // The fixture will clear in TearDown; this verifies basic integrity
  EXPECT_NE(network_.findChild(top, "u1"), nullptr);
}

// R10_ ConcreteInstance: cell() accessor
// Covers: ConcreteInstance::cell() const
TEST_F(ConcreteNetworkLinkedTest, InstanceCellAccessor) {
  Cell *cell = network_.cell(u1_);
  ASSERT_NE(cell, nullptr);
  EXPECT_STREQ(network_.name(cell), "INV");
  // Also test on top instance
  Cell *top_cell = network_.cell(network_.topInstance());
  ASSERT_NE(top_cell, nullptr);
  EXPECT_STREQ(network_.name(top_cell), "TOP");
}

// R10_ ConcreteInstance: findChild via network interface
// Covers: ConcreteInstance::findChild(const char*) const
TEST_F(ConcreteNetworkLinkedTest, FindChildExhaustive) {
  Instance *top = network_.topInstance();
  Instance *c1 = network_.findChild(top, "u1");
  Instance *c2 = network_.findChild(top, "u2");
  EXPECT_EQ(c1, u1_);
  EXPECT_EQ(c2, u2_);
  Instance *c3 = network_.findChild(top, "nonexistent");
  EXPECT_EQ(c3, nullptr);
  // Leaf instances have no children
  Instance *c4 = network_.findChild(u1_, "any");
  EXPECT_EQ(c4, nullptr);
}

// R10_ ConcreteInstance: findPin(Port*) via network interface
// Covers: ConcreteInstance::findPin(Port const*) const
TEST_F(ConcreteNetworkLinkedTest, FindPinByPort4) {
  Cell *inv_cell = network_.cell(u1_);
  Port *port_a = network_.findPort(inv_cell, "A");
  Port *port_y = network_.findPort(inv_cell, "Y");
  ASSERT_NE(port_a, nullptr);
  ASSERT_NE(port_y, nullptr);

  Pin *p_a = network_.findPin(u1_, port_a);
  Pin *p_y = network_.findPin(u1_, port_y);
  EXPECT_EQ(p_a, pin_u1_a_);
  EXPECT_EQ(p_y, pin_u1_y_);
}

// R10_ ConcreteInstance: deleteChild then verify
// Covers: ConcreteInstance::deleteChild(ConcreteInstance*)
TEST_F(ConcreteNetworkLinkedTest, DeleteChildAndVerify) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.cell(u1_);
  Instance *extra = network_.makeInstance(inv_cell, "extra", top);
  ASSERT_NE(extra, nullptr);

  // Verify it exists
  Instance *found = network_.findChild(top, "extra");
  EXPECT_EQ(found, extra);

  // Delete it
  network_.deleteInstance(extra);

  // Verify it's gone
  found = network_.findChild(top, "extra");
  EXPECT_EQ(found, nullptr);
}

// R10_ ConcreteInstance: addNet and deleteNet
// Covers: ConcreteInstance::addNet, ConcreteInstance::deleteNet, ConcreteNet::~ConcreteNet
TEST_F(ConcreteNetworkLinkedTest, AddDeleteNetExhaustive) {
  Instance *top = network_.topInstance();
  Net *n4 = network_.makeNet("n4", top);
  ASSERT_NE(n4, nullptr);

  // Verify the net exists
  Net *found = network_.findNet(top, "n4");
  EXPECT_EQ(found, n4);

  // Delete the net
  network_.deleteNet(n4);

  // Verify it's gone
  found = network_.findNet(top, "n4");
  EXPECT_EQ(found, nullptr);
}

// R10_ ConcreteInstance: setCell
// Covers: ConcreteInstance::setCell(ConcreteCell*)
TEST_F(ConcreteNetworkLinkedTest, SetCellOnInstance) {
  // Create a second cell type
  Cell *buf_cell = network_.makeCell(lib_, "BUF2", true, "test.lib");
  network_.makePort(buf_cell, "A");
  network_.makePort(buf_cell, "Y");
  network_.setDirection(network_.findPort(buf_cell, "A"), PortDirection::input());
  network_.setDirection(network_.findPort(buf_cell, "Y"), PortDirection::output());

  // Replace cell of u1
  network_.replaceCell(u1_, buf_cell);
  Cell *new_cell = network_.cell(u1_);
  EXPECT_STREQ(network_.name(new_cell), "BUF2");
}

// R10_ ConcretePin: port name via port accessor
// Covers: ConcretePin internal paths
TEST_F(ConcreteNetworkLinkedTest, PinPortName2) {
  Port *port = network_.port(pin_u1_a_);
  ASSERT_NE(port, nullptr);
  const char *name = network_.name(port);
  EXPECT_STREQ(name, "A");
}

// R10_ ConcretePin: setVertexId
// Covers: ConcretePin::setVertexId(unsigned int)
TEST_F(ConcreteNetworkLinkedTest, PinSetVertexIdMultiple2) {
  network_.setVertexId(pin_u1_a_, 100);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 100u);
  network_.setVertexId(pin_u1_a_, 200);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 200u);
  network_.setVertexId(pin_u1_a_, 0);
  EXPECT_EQ(network_.vertexId(pin_u1_a_), 0u);
}

// R10_ ConcreteNet: pin iteration and manipulation
// Covers: ConcreteNet::addPin, ConcreteNetPinIterator ctor
TEST_F(ConcreteNetworkLinkedTest, NetPinIteration) {
  // net2_ connects u1.Y and u2.A
  NetPinIterator *iter = network_.pinIterator(net2_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    const Pin *pin = iter->next();
    EXPECT_NE(pin, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);  // u1.Y and u2.A
}

// R10_ ConcreteNet: term iteration
// Covers: ConcreteNet::addTerm, ConcreteNetTermIterator ctor
TEST_F(ConcreteNetworkLinkedTest, NetTermIteration) {
  // Leaf-level nets don't have terms, but let's verify the iterator works
  NetTermIterator *iter = network_.termIterator(net1_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    iter->next();
    count++;
  }
  delete iter;
  // Terms exist on top-level ports connected to nets
  EXPECT_GE(count, 0);
}

// R10_ Iterators: library iterator
// Covers: ConcreteLibraryIterator1 ctor
TEST_F(ConcreteNetworkLinkedTest, LibraryIteratorMultiple) {
  // Create a second library
  Library *lib2 = network_.makeLibrary("test_lib2", "test2.lib");
  ASSERT_NE(lib2, nullptr);

  LibraryIterator *iter = network_.libraryIterator();
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Library *lib = iter->next();
    EXPECT_NE(lib, nullptr);
    count++;
  }
  delete iter;
  EXPECT_GE(count, 2);
}

// R10_ Iterators: liberty library iterator
// Covers: ConcreteLibertyLibraryIterator ctor/dtor
TEST_F(ConcreteNetworkLinkedTest, LibertyLibraryIterator2) {
  LibertyLibraryIterator *iter = network_.libertyLibraryIterator();
  ASSERT_NE(iter, nullptr);
  // No liberty libs in this test fixture
  EXPECT_FALSE(iter->hasNext());
  delete iter;
}

// R10_ Iterators: cell port iterator
// Covers: ConcreteCellPortIterator1 ctor
TEST_F(ConcreteNetworkLinkedTest, CellPortIteratorOnTopCell) {
  Cell *top_cell = network_.cell(network_.topInstance());
  CellPortIterator *iter = network_.portIterator(top_cell);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Port *port = iter->next();
    EXPECT_NE(port, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 3);  // clk, data_in, data_out
}

// R10_ Iterators: cell port bit iterator
// Covers: ConcreteCellPortBitIterator ctor, ConcreteCellPortBitIterator1 ctor
TEST_F(ConcreteNetworkLinkedTest, CellPortBitIteratorOnTopCell) {
  Cell *top_cell = network_.cell(network_.topInstance());
  CellPortBitIterator *iter = network_.portBitIterator(top_cell);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Port *port = iter->next();
    EXPECT_NE(port, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 3);
}

// R10_ Iterators: instance child iterator
// Covers: ConcreteInstanceChildIterator ctor
TEST_F(ConcreteNetworkLinkedTest, InstanceChildIteratorCount) {
  Instance *top = network_.topInstance();
  InstanceChildIterator *iter = network_.childIterator(top);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Instance *child = iter->next();
    EXPECT_NE(child, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);
}

// R10_ Iterators: instance pin iterator
// Covers: ConcreteInstancePinIterator ctor
TEST_F(ConcreteNetworkLinkedTest, InstancePinIteratorOnU2) {
  InstancePinIterator *iter = network_.pinIterator(u2_);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Pin *pin = iter->next();
    EXPECT_NE(pin, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 2);  // A, Y
}

// R10_ Iterators: port member iterator (for bus port)
// Covers: ConcretePortMemberIterator1 ctor
TEST_F(ConcreteNetworkLinkedTest, PortMemberIterator) {
  // Create on a new cell to avoid instance pin mismatch
  Cell *bus_cell2 = network_.makeCell(lib_, "BUS_TEST2", true, "test.lib");
  Port *bus = network_.makeBusPort(bus_cell2, "test_bus", 0, 3);
  ASSERT_NE(bus, nullptr);

  PortMemberIterator *iter = network_.memberIterator(bus);
  ASSERT_NE(iter, nullptr);
  int count = 0;
  while (iter->hasNext()) {
    Port *member = iter->next();
    EXPECT_NE(member, nullptr);
    count++;
  }
  delete iter;
  EXPECT_EQ(count, 4);  // bits 0..3
}

// R10_ Network: hasMembers for scalar port
// Covers: Network::hasMembers(Port const*) const
TEST_F(ConcreteNetworkLinkedTest, HasMembersScalar2) {
  Cell *inv_cell = network_.cell(u1_);
  Port *port_a = network_.findPort(inv_cell, "A");
  EXPECT_FALSE(network_.hasMembers(port_a));
}

// R10_ Network: findPinLinear
// Covers: Network::findPinLinear(Instance const*, char const*) const
TEST_F(ConcreteNetworkLinkedTest, FindPinLinear2) {
  Pin *pin = network_.findPin(u1_, "A");
  EXPECT_EQ(pin, pin_u1_a_);
  Pin *null_pin = network_.findPin(u1_, "nonexistent");
  EXPECT_EQ(null_pin, nullptr);
}

// R10_ Network: findNetLinear
// Covers: Network::findNetLinear(Instance const*, char const*) const
TEST_F(ConcreteNetworkLinkedTest, FindNetByNameLinear) {
  Instance *top = network_.topInstance();
  Net *net = network_.findNet(top, "n1");
  EXPECT_EQ(net, net1_);
  Net *null_net = network_.findNet(top, "nonexistent_net");
  EXPECT_EQ(null_net, nullptr);
}

// R10_ Network: findNetsMatchingLinear with wildcard
// Covers: Network::findNetsMatchingLinear(Instance const*, PatternMatch const*) const
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatchingWildcard) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("n*");
  NetSeq matches;
  network_.findNetsMatching(top, &pattern, matches);
  EXPECT_EQ(matches.size(), 3u);  // n1, n2, n3
}

// R10_ Network: findNetsMatchingLinear with exact match
TEST_F(ConcreteNetworkLinkedTest, FindNetsMatchingExact) {
  Instance *top = network_.topInstance();
  PatternMatch pattern("n2");
  NetSeq matches;
  network_.findNetsMatching(top, &pattern, matches);
  EXPECT_EQ(matches.size(), 1u);
}

// R10_ NetworkEdit: connectPin(Pin*, Net*)
// Covers: NetworkEdit::connectPin(Pin*, Net*)
TEST_F(ConcreteNetworkLinkedTest, ConnectPinReconnect) {
  // Disconnect pin_u1_a_ from net1_ and reconnect to net3_
  network_.disconnectPin(pin_u1_a_);
  Pin *reconnected = network_.connect(u1_,
    network_.findPort(network_.cell(u1_), "A"), net3_);
  ASSERT_NE(reconnected, nullptr);
  EXPECT_EQ(network_.net(reconnected), net3_);
}

// R10_ NetworkEdit: disconnect and verify iteration
TEST_F(ConcreteNetworkLinkedTest, DisconnectPinVerifyNet) {
  // Count pins on net2_ before disconnect
  NetPinIterator *iter = network_.pinIterator(net2_);
  int before_count = 0;
  while (iter->hasNext()) { iter->next(); before_count++; }
  delete iter;
  EXPECT_EQ(before_count, 2);

  // Disconnect u2.A from net2
  network_.disconnectPin(pin_u2_a_);

  // Count after
  iter = network_.pinIterator(net2_);
  int after_count = 0;
  while (iter->hasNext()) { iter->next(); after_count++; }
  delete iter;
  EXPECT_EQ(after_count, 1);
}

// R10_ NetworkAdapter: hasMembers forwarding on scalar port
// Covers: NetworkNameAdapter hasMembers path
TEST_F(NetworkAdapterTest, AdapterHasMembersScalar) {
  EXPECT_FALSE(sdc_net_->hasMembers(port_a_));
  EXPECT_FALSE(sdc_net_->isBus(port_a_));
  EXPECT_FALSE(sdc_net_->isBundle(port_a_));
}

// R10_ NetworkAdapter: port size forwarding
// Covers: NetworkNameAdapter size path
TEST_F(NetworkAdapterTest, AdapterPortSize2) {
  int size = sdc_net_->size(port_a_);
  EXPECT_EQ(size, 1);  // Scalar port has size 1
}

// R10_ NetworkAdapter: name(Port) forwarding
// Covers: NetworkNameAdapter::name(Port const*) const
TEST_F(NetworkAdapterTest, AdapterPortName3) {
  const char *name = sdc_net_->name(port_a_);
  EXPECT_STREQ(name, "A");
}

// R10_ NetworkAdapter: busName forwarding
// Covers: NetworkNameAdapter::busName(Port const*) const
TEST_F(NetworkAdapterTest, AdapterBusName) {
  const char *name = sdc_net_->busName(port_a_);
  // Scalar port busName may be nullptr or same as port name
  if (name != nullptr) {
    EXPECT_STREQ(name, "A");
  }
}

// R10_ NetworkAdapter: makeNet forwarding
// Covers: NetworkNameAdapter::makeNet(char const*, Instance*)
TEST_F(NetworkAdapterTest, AdapterMakeNet3) {
  Instance *top = sdc_net_->topInstance();
  Net *net = sdc_net_->makeNet("adapter_net", top);
  ASSERT_NE(net, nullptr);
  Net *found = sdc_net_->findNet(top, "adapter_net");
  EXPECT_EQ(found, net);
}

// R10_ NetworkAdapter: findPort forwarding
// Covers: NetworkNameAdapter::findPort(Cell const*, char const*) const
TEST_F(NetworkAdapterTest, AdapterFindPortByName2) {
  Port *found = sdc_net_->findPort(inv_cell_, "A");
  EXPECT_EQ(found, port_a_);
  Port *not_found = sdc_net_->findPort(inv_cell_, "nonexistent");
  EXPECT_EQ(not_found, nullptr);
}

// R10_ NetworkAdapter: findPortsMatching forwarding
// Covers: NetworkNameAdapter::findPortsMatching(Cell const*, PatternMatch const*) const
TEST_F(NetworkAdapterTest, AdapterFindPortsMatchingWild) {
  PatternMatch pattern("*");
  PortSeq ports = sdc_net_->findPortsMatching(inv_cell_, &pattern);
  EXPECT_EQ(ports.size(), 2u);  // A, Y
}

// R10_ NetworkAdapter: findPin(Instance, Port) forwarding
// Covers: NetworkNameAdapter::findPin(Instance const*, Port const*) const
TEST_F(NetworkAdapterTest, AdapterFindPinByPort2) {
  Pin *pin = sdc_net_->findPin(u1_, port_a_);
  EXPECT_EQ(pin, pin_b1_a_);
}

// R10_ ConcreteNetwork: merge nets exercise
// Covers: ConcreteNet pin/term manipulation, mergeInto
TEST_F(ConcreteNetworkLinkedTest, MergeNetsAndVerify) {
  Instance *top = network_.topInstance();
  Net *merge_src = network_.makeNet("merge_src", top);
  Net *merge_dst = network_.makeNet("merge_dst", top);
  ASSERT_NE(merge_src, nullptr);
  ASSERT_NE(merge_dst, nullptr);

  // Connect a pin to source net
  Cell *inv_cell = network_.cell(u1_);
  Instance *extra = network_.makeInstance(inv_cell, "merge_inst", top);
  Port *port_a = network_.findPort(inv_cell, "A");
  network_.connect(extra, port_a, merge_src);

  // Merge src into dst
  network_.mergeInto(merge_src, merge_dst);

  // Verify merged
  Net *merged = network_.mergedInto(merge_src);
  EXPECT_EQ(merged, merge_dst);

  network_.deleteInstance(extra);
}

// R10_ ConcreteInstance: initPins explicit exercise
// Covers: ConcreteInstance::initPins
TEST_F(ConcreteNetworkLinkedTest, InitPinsExercise2) {
  // makeInstance already calls initPins, but let's create a new instance
  // and verify pins are initialized properly
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.cell(u1_);
  Instance *new_inst = network_.makeInstance(inv_cell, "init_test", top);
  ASSERT_NE(new_inst, nullptr);

  // Pins should be initialized (nullptr but accessible)
  Pin *pin = network_.findPin(new_inst, "A");
  EXPECT_EQ(pin, nullptr);  // Not connected yet

  // Connect and verify
  Pin *connected = network_.connect(new_inst,
    network_.findPort(inv_cell, "A"), net1_);
  EXPECT_NE(connected, nullptr);
  EXPECT_EQ(network_.net(connected), net1_);

  network_.deleteInstance(new_inst);
}

// R10_ ConcreteInstance: disconnect pin exercises internal paths
// Covers: disconnect/connect paths for pins
TEST_F(ConcreteNetworkLinkedTest, DisconnectPinExercise) {
  Instance *top = network_.topInstance();
  Cell *inv_cell = network_.cell(u1_);
  Instance *dp_inst = network_.makeInstance(inv_cell, "dp_test", top);
  Port *port_a = network_.findPort(inv_cell, "A");
  Pin *dp_pin = network_.connect(dp_inst, port_a, net1_);
  EXPECT_NE(dp_pin, nullptr);
  EXPECT_EQ(network_.net(dp_pin), net1_);

  // Disconnect removes pin from net
  network_.disconnectPin(dp_pin);
  // After disconnect, the pin's net should be nullptr
  EXPECT_EQ(network_.net(dp_pin), nullptr);

  network_.deleteInstance(dp_inst);
}

// R10_ Network: multiple libraries and find
TEST_F(ConcreteNetworkLinkedTest, MultipleCellsAndFind) {
  // Create cells in a new library
  Library *lib2 = network_.makeLibrary("other_lib", "other.lib");
  Cell *nand = network_.makeCell(lib2, "NAND2", true, "other.lib");
  network_.makePort(nand, "A");
  network_.makePort(nand, "B");
  network_.makePort(nand, "Y");

  // Find the cell
  Cell *found = network_.findCell(lib2, "NAND2");
  EXPECT_EQ(found, nand);
  Cell *not_found = network_.findCell(lib2, "nonexistent");
  EXPECT_EQ(not_found, nullptr);
}

// R10_ ConcreteNetwork: findPin across multiple instances
TEST_F(ConcreteNetworkLinkedTest, FindPinAllInstances) {
  // Check all instances
  Pin *u1a = network_.findPin(u1_, "A");
  Pin *u1y = network_.findPin(u1_, "Y");
  Pin *u2a = network_.findPin(u2_, "A");
  Pin *u2y = network_.findPin(u2_, "Y");
  EXPECT_EQ(u1a, pin_u1_a_);
  EXPECT_EQ(u1y, pin_u1_y_);
  EXPECT_EQ(u2a, pin_u2_a_);
  EXPECT_EQ(u2y, pin_u2_y_);
}

} // namespace sta