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from pathlib import Path
from unittest.mock import MagicMock
import pytest
from codebase_rag.tests.conftest import get_node_names, get_relationships, run_updater
@pytest.fixture
def cpp_smart_pointers_project(temp_repo: Path) -> Path:
"""Create a comprehensive C++ project with smart pointer patterns."""
project_path = temp_repo / "cpp_smart_pointers_test"
project_path.mkdir()
(project_path / "src").mkdir()
(project_path / "include").mkdir()
return project_path
def test_unique_ptr_patterns(
cpp_smart_pointers_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test unique_ptr usage patterns and ownership semantics."""
test_file = cpp_smart_pointers_project / "unique_ptr_patterns.cpp"
test_file.write_text(
"""
#include <iostream>
#include <memory>
#include <vector>
#include <string>
#include <utility>
// Simple resource class
class Resource {
private:
std::string name_;
int value_;
public:
Resource(const std::string& name, int value)
: name_(name), value_(value) {
std::cout << "Resource " << name_ << " created" << std::endl;
}
~Resource() {
std::cout << "Resource " << name_ << " destroyed" << std::endl;
}
// Delete copy operations
Resource(const Resource&) = delete;
Resource& operator=(const Resource&) = delete;
// Allow move operations
Resource(Resource&& other) noexcept
: name_(std::move(other.name_)), value_(other.value_) {
other.value_ = 0;
}
Resource& operator=(Resource&& other) noexcept {
if (this != &other) {
name_ = std::move(other.name_);
value_ = other.value_;
other.value_ = 0;
}
return *this;
}
void use() const {
std::cout << "Using resource " << name_ << " with value " << value_ << std::endl;
}
const std::string& getName() const { return name_; }
int getValue() const { return value_; }
};
// Factory function returning unique_ptr
std::unique_ptr<Resource> createResource(const std::string& name, int value) {
return std::make_unique<Resource>(name, value);
}
// Function taking ownership
void takeOwnership(std::unique_ptr<Resource> resource) {
std::cout << "Taking ownership of " << resource->getName() << std::endl;
resource->use();
// Resource will be destroyed when function exits
}
// Function borrowing resource
void borrowResource(const Resource* resource) {
if (resource) {
std::cout << "Borrowing " << resource->getName() << std::endl;
resource->use();
}
}
// Container managing unique_ptr collection
class ResourceManager {
private:
std::vector<std::unique_ptr<Resource>> resources_;
public:
void addResource(std::unique_ptr<Resource> resource) {
resources_.push_back(std::move(resource));
}
void addResource(const std::string& name, int value) {
resources_.push_back(std::make_unique<Resource>(name, value));
}
Resource* getResource(size_t index) {
if (index < resources_.size()) {
return resources_[index].get();
}
return nullptr;
}
std::unique_ptr<Resource> releaseResource(size_t index) {
if (index < resources_.size()) {
auto resource = std::move(resources_[index]);
resources_.erase(resources_.begin() + index);
return resource;
}
return nullptr;
}
void clearAll() {
resources_.clear();
}
size_t size() const { return resources_.size(); }
void useAll() const {
for (const auto& resource : resources_) {
if (resource) {
resource->use();
}
}
}
};
// Custom deleter example
struct FileDeleter {
void operator()(FILE* file) const {
if (file) {
std::cout << "Closing file with custom deleter" << std::endl;
fclose(file);
}
}
};
// Array deleter
template<typename T>
struct ArrayDeleter {
void operator()(T* array) const {
std::cout << "Deleting array with custom deleter" << std::endl;
delete[] array;
}
};
// Smart pointer wrapper for legacy APIs
class LegacyResourceWrapper {
private:
std::unique_ptr<void, std::function<void(void*)>> resource_;
public:
LegacyResourceWrapper(void* resource, std::function<void(void*)> deleter)
: resource_(resource, deleter) {}
void* get() const { return resource_.get(); }
void* release() { return resource_.release(); }
};
void demonstrateUniquePtrBasics() {
std::cout << "=== Unique Pointer Basics ===" << std::endl;
// Basic creation and destruction
{
auto resource = std::make_unique<Resource>("Basic", 100);
resource->use();
} // Resource destroyed here
// Moving ownership
auto resource1 = std::make_unique<Resource>("Movable", 200);
auto resource2 = std::move(resource1);
// resource1 is now empty
if (!resource1) {
std::cout << "resource1 is empty after move" << std::endl;
}
resource2->use();
// Factory pattern
auto factoryResource = createResource("Factory", 300);
factoryResource->use();
// Passing ownership
auto transferResource = std::make_unique<Resource>("Transfer", 400);
takeOwnership(std::move(transferResource));
// transferResource is now empty
// Borrowing without ownership
auto borrowedResource = std::make_unique<Resource>("Borrowed", 500);
borrowResource(borrowedResource.get());
// borrowedResource still owns the resource
// Reset and release
auto resetResource = std::make_unique<Resource>("Reset", 600);
resetResource.reset(); // Destroys current resource
resetResource = std::make_unique<Resource>("New", 700);
Resource* rawPtr = resetResource.release(); // Releases ownership
delete rawPtr; // Manual cleanup required
}
void demonstrateUniquePtrContainers() {
std::cout << "=== Unique Pointer Containers ===" << std::endl;
ResourceManager manager;
// Add resources
manager.addResource(std::make_unique<Resource>("First", 1));
manager.addResource("Second", 2);
manager.addResource(createResource("Third", 3));
// Use resources
manager.useAll();
// Borrow a resource
if (auto* resource = manager.getResource(1)) {
borrowResource(resource);
}
// Transfer ownership out
auto extracted = manager.releaseResource(0);
if (extracted) {
std::cout << "Extracted: ";
extracted->use();
}
std::cout << "Remaining resources: " << manager.size() << std::endl;
manager.useAll();
// Clear all
manager.clearAll();
std::cout << "After clear: " << manager.size() << " resources" << std::endl;
}
void demonstrateCustomDeleters() {
std::cout << "=== Custom Deleters ===" << std::endl;
// File with custom deleter
{
std::unique_ptr<FILE, FileDeleter> file(
fopen("test.txt", "w"),
FileDeleter()
);
if (file) {
fprintf(file.get(), "Hello from unique_ptr\n");
}
} // File automatically closed
// Array with custom deleter
{
std::unique_ptr<int, ArrayDeleter<int>> array(
new int[5]{1, 2, 3, 4, 5},
ArrayDeleter<int>()
);
for (int i = 0; i < 5; ++i) {
std::cout << "Array[" << i << "] = " << array.get()[i] << std::endl;
}
} // Array deleted with custom deleter
// Lambda deleter
{
auto deleter = [](Resource* r) {
std::cout << "Lambda deleter for " << r->getName() << std::endl;
delete r;
};
std::unique_ptr<Resource, decltype(deleter)> resource(
new Resource("Lambda", 800),
deleter
);
resource->use();
}
// Function deleter
{
auto customFree = [](void* ptr) {
std::cout << "Custom free function" << std::endl;
free(ptr);
};
std::unique_ptr<char, decltype(customFree)> buffer(
static_cast<char*>(malloc(100)),
customFree
);
if (buffer) {
strcpy(buffer.get(), "Hello");
std::cout << "Buffer: " << buffer.get() << std::endl;
}
}
}
// Polymorphic unique_ptr
class Base {
public:
virtual ~Base() = default;
virtual void process() const = 0;
};
class DerivedA : public Base {
public:
void process() const override {
std::cout << "DerivedA processing" << std::endl;
}
};
class DerivedB : public Base {
public:
void process() const override {
std::cout << "DerivedB processing" << std::endl;
}
};
std::unique_ptr<Base> createPolymorphic(char type) {
switch (type) {
case 'A':
return std::make_unique<DerivedA>();
case 'B':
return std::make_unique<DerivedB>();
default:
return nullptr;
}
}
void demonstratePolymorphicUniquePtr() {
std::cout << "=== Polymorphic Unique Pointers ===" << std::endl;
std::vector<std::unique_ptr<Base>> polymorphic;
polymorphic.push_back(createPolymorphic('A'));
polymorphic.push_back(createPolymorphic('B'));
polymorphic.push_back(std::make_unique<DerivedA>());
for (const auto& ptr : polymorphic) {
if (ptr) {
ptr->process();
}
}
}
"""
)
run_updater(cpp_smart_pointers_project, mock_ingestor)
project_name = cpp_smart_pointers_project.name
expected_entities = [
f"{project_name}.unique_ptr_patterns.Resource",
f"{project_name}.unique_ptr_patterns.ResourceManager",
f"{project_name}.unique_ptr_patterns.FileDeleter",
f"{project_name}.unique_ptr_patterns.createResource",
f"{project_name}.unique_ptr_patterns.demonstrateUniquePtrBasics",
]
all_calls = mock_ingestor.ensure_node_batch.call_args_list
class_calls = [call for call in all_calls if call[0][0] == "Class"]
function_calls = [call for call in all_calls if call[0][0] == "Function"]
created_entities = {
call[0][1]["qualified_name"] for call in class_calls + function_calls
}
found_entities = [
entity for entity in expected_entities if entity in created_entities
]
assert len(found_entities) >= 4, (
f"Expected at least 4 unique_ptr entities, found {len(found_entities)}: {found_entities}"
)
def test_shared_ptr_patterns(
cpp_smart_pointers_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test shared_ptr usage patterns and reference counting."""
test_file = cpp_smart_pointers_project / "shared_ptr_patterns.cpp"
test_file.write_text(
"""
#include <iostream>
#include <memory>
#include <vector>
#include <map>
#include <thread>
#include <mutex>
// Node for circular reference demonstration
class Node {
private:
std::string name_;
std::shared_ptr<Node> next_;
std::weak_ptr<Node> parent_; // Use weak_ptr to avoid cycles
public:
Node(const std::string& name) : name_(name) {
std::cout << "Node " << name_ << " created" << std::endl;
}
~Node() {
std::cout << "Node " << name_ << " destroyed" << std::endl;
}
void setNext(std::shared_ptr<Node> node) {
next_ = node;
}
void setParent(std::shared_ptr<Node> node) {
parent_ = node;
}
std::shared_ptr<Node> getNext() const { return next_; }
std::shared_ptr<Node> getParent() const {
return parent_.lock(); // Convert weak_ptr to shared_ptr
}
const std::string& getName() const { return name_; }
void printChain() const {
std::cout << name_;
if (next_) {
std::cout << " -> ";
next_->printChain();
} else {
std::cout << std::endl;
}
}
};
// Observer pattern with weak_ptr
class Subject;
class Observer {
public:
virtual ~Observer() = default;
virtual void update(const Subject* subject) = 0;
};
class Subject {
private:
std::vector<std::weak_ptr<Observer>> observers_;
std::string state_;
mutable std::mutex mutex_;
public:
void attach(std::shared_ptr<Observer> observer) {
std::lock_guard<std::mutex> lock(mutex_);
observers_.push_back(observer);
}
void setState(const std::string& state) {
{
std::lock_guard<std::mutex> lock(mutex_);
state_ = state;
}
notify();
}
std::string getState() const {
std::lock_guard<std::mutex> lock(mutex_);
return state_;
}
private:
void notify() {
std::lock_guard<std::mutex> lock(mutex_);
// Remove expired observers
observers_.erase(
std::remove_if(observers_.begin(), observers_.end(),
[](const std::weak_ptr<Observer>& wp) { return wp.expired(); }),
observers_.end()
);
// Notify remaining observers
for (const auto& wp : observers_) {
if (auto observer = wp.lock()) {
observer->update(this);
}
}
}
};
class ConcreteObserver : public Observer,
public std::enable_shared_from_this<ConcreteObserver> {
private:
std::string name_;
public:
ConcreteObserver(const std::string& name) : name_(name) {}
void update(const Subject* subject) override {
std::cout << name_ << " received update: " << subject->getState() << std::endl;
}
void registerWith(std::shared_ptr<Subject> subject) {
subject->attach(shared_from_this());
}
};
// Cache with shared_ptr
template<typename Key, typename Value>
class Cache {
private:
mutable std::map<Key, std::shared_ptr<Value>> cache_;
mutable std::mutex mutex_;
size_t max_size_;
public:
Cache(size_t max_size = 100) : max_size_(max_size) {}
void put(const Key& key, std::shared_ptr<Value> value) {
std::lock_guard<std::mutex> lock(mutex_);
if (cache_.size() >= max_size_ && cache_.find(key) == cache_.end()) {
// Remove oldest entry (simplified - just remove first)
cache_.erase(cache_.begin());
}
cache_[key] = value;
}
std::shared_ptr<Value> get(const Key& key) const {
std::lock_guard<std::mutex> lock(mutex_);
auto it = cache_.find(key);
if (it != cache_.end()) {
return it->second;
}
return nullptr;
}
size_t size() const {
std::lock_guard<std::mutex> lock(mutex_);
return cache_.size();
}
void clear() {
std::lock_guard<std::mutex> lock(mutex_);
cache_.clear();
}
};
// Thread-safe reference counting
class ThreadSafeResource {
private:
std::string data_;
mutable std::mutex mutex_;
public:
ThreadSafeResource(const std::string& data) : data_(data) {
std::cout << "ThreadSafeResource created: " << data_ << std::endl;
}
~ThreadSafeResource() {
std::cout << "ThreadSafeResource destroyed: " << data_ << std::endl;
}
void modify(const std::string& newData) {
std::lock_guard<std::mutex> lock(mutex_);
data_ = newData;
}
std::string read() const {
std::lock_guard<std::mutex> lock(mutex_);
return data_;
}
};
void demonstrateSharedPtrBasics() {
std::cout << "=== Shared Pointer Basics ===" << std::endl;
// Basic creation
auto shared1 = std::make_shared<Node>("First");
std::cout << "Reference count: " << shared1.use_count() << std::endl;
// Copy increases reference count
{
auto shared2 = shared1;
std::cout << "Reference count after copy: " << shared1.use_count() << std::endl;
auto shared3 = shared1;
std::cout << "Reference count with 3 pointers: " << shared1.use_count() << std::endl;
} // shared2 and shared3 destroyed, count decreases
std::cout << "Reference count after scope: " << shared1.use_count() << std::endl;
// Move doesn't increase count
auto shared4 = std::make_shared<Node>("Second");
auto shared5 = std::move(shared4);
if (!shared4) {
std::cout << "shared4 is empty after move" << std::endl;
}
std::cout << "shared5 count: " << shared5.use_count() << std::endl;
// Reset
shared1.reset(); // Decreases count, may destroy object
std::cout << "After reset, shared1 is " << (shared1 ? "valid" : "empty") << std::endl;
}
void demonstrateCircularReferences() {
std::cout << "=== Circular References ===" << std::endl;
// Problem: circular reference with shared_ptr
{
auto node1 = std::make_shared<Node>("Circular1");
auto node2 = std::make_shared<Node>("Circular2");
// This would create a circular reference if next_ was shared_ptr for both
// node1->setNext(node2);
// node2->setNext(node1); // Memory leak!
// Solution: use weak_ptr for one direction
node1->setNext(node2);
node2->setParent(node1); // parent_ is weak_ptr
std::cout << "node1 count: " << node1.use_count() << std::endl;
std::cout << "node2 count: " << node2.use_count() << std::endl;
} // Both nodes properly destroyed
// Linked list with proper cleanup
{
auto head = std::make_shared<Node>("Head");
auto middle = std::make_shared<Node>("Middle");
auto tail = std::make_shared<Node>("Tail");
head->setNext(middle);
middle->setNext(tail);
// Set parents using weak_ptr
middle->setParent(head);
tail->setParent(middle);
head->printChain();
} // All nodes properly destroyed
}
void demonstrateObserverPattern() {
std::cout << "=== Observer Pattern with weak_ptr ===" << std::endl;
auto subject = std::make_shared<Subject>();
{
auto observer1 = std::make_shared<ConcreteObserver>("Observer1");
auto observer2 = std::make_shared<ConcreteObserver>("Observer2");
observer1->registerWith(subject);
observer2->registerWith(subject);
subject->setState("State A");
{
auto observer3 = std::make_shared<ConcreteObserver>("Observer3");
observer3->registerWith(subject);
subject->setState("State B");
} // observer3 destroyed
subject->setState("State C"); // observer3 automatically removed
} // observer1 and observer2 destroyed
subject->setState("State D"); // No observers, but no crash
}
void demonstrateThreadSafety() {
std::cout << "=== Thread Safety with shared_ptr ===" << std::endl;
auto resource = std::make_shared<ThreadSafeResource>("Shared Data");
std::vector<std::thread> threads;
// Multiple threads sharing the resource
for (int i = 0; i < 5; ++i) {
threads.emplace_back([resource, i]() {
// Each thread has its own shared_ptr copy
std::cout << "Thread " << i << " count: " << resource.use_count() << std::endl;
resource->modify("Modified by thread " + std::to_string(i));
std::this_thread::sleep_for(std::chrono::milliseconds(10));
std::cout << "Thread " << i << " read: " << resource->read() << std::endl;
});
}
for (auto& t : threads) {
t.join();
}
std::cout << "Final count: " << resource.use_count() << std::endl;
}
void demonstrateCaching() {
std::cout << "=== Caching with shared_ptr ===" << std::endl;
Cache<std::string, Node> cache(3);
// Add items to cache
cache.put("node1", std::make_shared<Node>("Cached1"));
cache.put("node2", std::make_shared<Node>("Cached2"));
cache.put("node3", std::make_shared<Node>("Cached3"));
// Retrieve from cache
if (auto node = cache.get("node2")) {
std::cout << "Retrieved from cache: " << node->getName() << std::endl;
std::cout << "Reference count: " << node.use_count() << std::endl;
}
// Add more items (causes eviction)
cache.put("node4", std::make_shared<Node>("Cached4"));
// Try to get evicted item
if (!cache.get("node1")) {
std::cout << "node1 was evicted from cache" << std::endl;
}
std::cout << "Cache size: " << cache.size() << std::endl;
// Clear cache
cache.clear();
std::cout << "Cache size after clear: " << cache.size() << std::endl;
}
// Custom allocator
template<typename T>
struct CustomAllocator {
using value_type = T;
T* allocate(std::size_t n) {
std::cout << "Custom allocating " << n << " objects" << std::endl;
return static_cast<T*>(::operator new(n * sizeof(T)));
}
void deallocate(T* p, std::size_t n) {
std::cout << "Custom deallocating " << n << " objects" << std::endl;
::operator delete(p);
}
};
void demonstrateAllocators() {
std::cout << "=== Custom Allocators ===" << std::endl;
// Allocate shared
auto ptr1 = std::allocate_shared<Node>(CustomAllocator<Node>(), "AllocatedNode");
ptr1->printChain();
// Array allocation
auto array = std::shared_ptr<int[]>(new int[5]{1, 2, 3, 4, 5});
for (int i = 0; i < 5; ++i) {
std::cout << "Array[" << i << "] = " << array[i] << std::endl;
}
}
"""
)
run_updater(cpp_smart_pointers_project, mock_ingestor)
project_name = cpp_smart_pointers_project.name
expected_classes = [
f"{project_name}.shared_ptr_patterns.Node",
f"{project_name}.shared_ptr_patterns.Observer",
f"{project_name}.shared_ptr_patterns.Subject",
f"{project_name}.shared_ptr_patterns.ConcreteObserver",
f"{project_name}.shared_ptr_patterns.Cache",
]
created_classes = get_node_names(mock_ingestor, "Class")
found_classes = [cls for cls in expected_classes if cls in created_classes]
assert len(found_classes) >= 4, (
f"Expected at least 4 shared_ptr classes, found {len(found_classes)}: {found_classes}"
)
def test_weak_ptr_and_advanced_patterns(
cpp_smart_pointers_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test weak_ptr usage and advanced smart pointer patterns."""
test_file = cpp_smart_pointers_project / "weak_ptr_advanced.cpp"
test_file.write_text(
"""
#include <iostream>
#include <memory>
#include <vector>
#include <unordered_map>
#include <functional>
// Tree structure with parent-child relationships
class TreeNode : public std::enable_shared_from_this<TreeNode> {
private:
std::string name_;
std::weak_ptr<TreeNode> parent_;
std::vector<std::shared_ptr<TreeNode>> children_;
public:
TreeNode(const std::string& name) : name_(name) {
std::cout << "TreeNode " << name_ << " created" << std::endl;
}
~TreeNode() {
std::cout << "TreeNode " << name_ << " destroyed" << std::endl;
}
void addChild(std::shared_ptr<TreeNode> child) {
children_.push_back(child);
child->parent_ = weak_from_this();
}
std::shared_ptr<TreeNode> getParent() const {
return parent_.lock();
}
const std::vector<std::shared_ptr<TreeNode>>& getChildren() const {
return children_;
}
std::string getPath() const {
if (auto p = parent_.lock()) {
return p->getPath() + "/" + name_;
}
return "/" + name_;
}
void printTree(int depth = 0) const {
std::string indent(depth * 2, ' ');
std::cout << indent << name_ << std::endl;
for (const auto& child : children_) {
child->printTree(depth + 1);
}
}
// Safe self-reference
std::shared_ptr<TreeNode> getSharedPtr() {
return shared_from_this();
}
// Weak self-reference
std::weak_ptr<TreeNode> weak_from_this() {
return shared_from_this();
}
};
// Event system with weak callbacks
class EventManager {
private:
using Callback = std::function<void(const std::string&)>;
using WeakCallback = std::pair<std::weak_ptr<void>, Callback>;
std::unordered_map<std::string, std::vector<WeakCallback>> listeners_;
public:
void subscribe(const std::string& event,
std::shared_ptr<void> owner,
Callback callback) {
listeners_[event].emplace_back(owner, callback);
}
void emit(const std::string& event, const std::string& data) {
auto it = listeners_.find(event);
if (it == listeners_.end()) return;
// Clean up expired listeners while emitting
auto& callbacks = it->second;
callbacks.erase(
std::remove_if(callbacks.begin(), callbacks.end(),
[&data](WeakCallback& wc) {
if (auto owner = wc.first.lock()) {
wc.second(data);
return false;
}
return true; // Remove expired
}),
callbacks.end()
);
}
size_t getListenerCount(const std::string& event) const {
auto it = listeners_.find(event);
if (it != listeners_.end()) {
return it->second.size();
}
return 0;
}
};
// Resource pool with weak references
template<typename T>
class ResourcePool {
private:
std::vector<std::weak_ptr<T>> available_;
std::vector<std::shared_ptr<T>> all_resources_;
std::function<std::shared_ptr<T>()> factory_;
public:
ResourcePool(std::function<std::shared_ptr<T>()> factory)
: factory_(factory) {}
std::shared_ptr<T> acquire() {
// Try to find an available resource
for (auto it = available_.begin(); it != available_.end(); ) {
if (auto resource = it->lock()) {
available_.erase(it);
return resource;
} else {
// Remove expired weak_ptr
it = available_.erase(it);
}
}
// Create new resource if none available
auto resource = factory_();
all_resources_.push_back(resource);
return resource;
}
void release(std::shared_ptr<T> resource) {
available_.push_back(resource);
}
size_t totalSize() const { return all_resources_.size(); }
size_t availableSize() const { return available_.size(); }
void cleanup() {
// Remove expired resources
available_.erase(
std::remove_if(available_.begin(), available_.end(),
[](const std::weak_ptr<T>& wp) { return wp.expired(); }),
available_.end()
);
all_resources_.erase(
std::remove_if(all_resources_.begin(), all_resources_.end(),
[](const std::shared_ptr<T>& sp) { return sp.use_count() == 1; }),
all_resources_.end()
);
}
};
// Cycle detection using weak_ptr
class GraphNode {
private:
std::string name_;
std::vector<std::shared_ptr<GraphNode>> strong_edges_;
std::vector<std::weak_ptr<GraphNode>> weak_edges_;
public:
GraphNode(const std::string& name) : name_(name) {}
void addStrongEdge(std::shared_ptr<GraphNode> node) {
strong_edges_.push_back(node);
}
void addWeakEdge(std::shared_ptr<GraphNode> node) {
weak_edges_.push_back(node);
}
bool hasCycleTo(std::shared_ptr<GraphNode> target,
std::unordered_set<GraphNode*>& visited) {
if (this == target.get()) return true;
if (visited.count(this)) return false;
visited.insert(this);
for (const auto& edge : strong_edges_) {
if (edge->hasCycleTo(target, visited)) return true;
}
for (const auto& weak_edge : weak_edges_) {
if (auto edge = weak_edge.lock()) {
if (edge->hasCycleTo(target, visited)) return true;
}
}
return false;
}
const std::string& getName() const { return name_; }
};
void demonstrateTreeStructure() {
std::cout << "=== Tree Structure with weak_ptr ===" << std::endl;