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"""
Comprehensive C++ attributes testing.
Tests C++11/14/17/20/23 attributes including [[nodiscard]], [[maybe_unused]], [[deprecated]],
[[fallthrough]], [[likely]], [[unlikely]], and compiler-specific attributes.
"""
from pathlib import Path
from typing import cast
from unittest.mock import MagicMock
import pytest
from codebase_rag.graph_updater import GraphUpdater
from codebase_rag.parser_loader import load_parsers
@pytest.fixture
def cpp_attributes_project(temp_repo: Path) -> Path:
"""Create a comprehensive C++ project with attribute patterns."""
project_path = temp_repo / "cpp_attributes_test"
project_path.mkdir()
# Create basic structure
(project_path / "src").mkdir()
(project_path / "include").mkdir()
# Create base files
(project_path / "include" / "attributes.h").write_text(
"#pragma once\nnamespace attr_test {}"
)
return project_path
def test_standard_attributes(
cpp_attributes_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test standard C++ attributes parsing and relationship tracking."""
test_file = cpp_attributes_project / "standard_attributes.cpp"
test_file.write_text(
"""
#include <iostream>
#include <string>
#include <memory>
#include <vector>
#include <optional>
// [[nodiscard]] attribute testing
[[nodiscard]] int calculateImportantValue() {
return 42;
}
[[nodiscard("Don't ignore the result!")]]
std::string createImportantString() {
return "Critical data";
}
[[nodiscard]] constexpr bool isValid(int value) noexcept {
return value > 0;
}
// [[maybe_unused]] attribute testing
void processData([[maybe_unused]] int debugMode,
[[maybe_unused]] const std::string& logLevel) {
// Implementation might not use all parameters in release builds
#ifdef DEBUG
std::cout << "Debug mode: " << debugMode << ", Level: " << logLevel << std::endl;
#endif
}
[[maybe_unused]] static int globalCounter = 0;
[[maybe_unused]] static void helperFunction() {
// Utility function that might not be used in all builds
globalCounter++;
}
// [[deprecated]] attribute testing
[[deprecated]]
void oldFunction() {
std::cout << "This function is deprecated" << std::endl;
}
[[deprecated("Use newImprovedFunction() instead")]]
int legacyCalculation(int x, int y) {
return x + y;
}
[[deprecated("This class will be removed in v2.0")]]
class LegacyClass {
public:
[[deprecated("Use getNewValue() instead")]]
int getOldValue() const { return value_; }
int getNewValue() const { return value_; }
private:
int value_ = 0;
};
// [[fallthrough]] attribute testing
std::string processSwitch(int value) {
std::string result;
switch (value) {
case 1:
result += "one";
[[fallthrough]];
case 2:
result += "two";
[[fallthrough]];
case 3:
result += "three";
break;
case 4:
result += "four";
[[fallthrough]];
default:
result += "default";
break;
}
return result;
}
// Complex switch with multiple fallthrough patterns
int complexSwitch(char c) {
switch (c) {
case 'a':
case 'A':
std::cout << "Letter A";
[[fallthrough]];
case 'e':
case 'E':
std::cout << " (vowel)";
return 1;
case 'b':
std::cout << "Letter B";
[[fallthrough]];
case 'c':
std::cout << " (consonant)";
return 2;
default:
return 0;
}
}
// [[likely]] and [[unlikely]] attributes (C++20)
int processConditions(int value) {
if (value > 0) [[likely]] {
// Most common case
return value * 2;
} else if (value < -100) [[unlikely]] {
// Rare error case
throw std::runtime_error("Invalid value");
} else {
// Uncommon but not rare
return 0;
}
}
// Complex branching with likelihood hints
std::optional<int> parseInput(const std::string& input) {
if (input.empty()) [[unlikely]] {
return std::nullopt;
}
if (input.length() > 1000) [[unlikely]] {
// Very long input is rare
return std::nullopt;
}
// Normal processing path
if (std::isdigit(input[0])) [[likely]] {
try {
return std::stoi(input);
} catch (...) [[unlikely]] {
return std::nullopt;
}
}
return std::nullopt;
}
// Combining multiple attributes
[[nodiscard]] [[deprecated("Use modernCalculation() instead")]]
int legacyImportantCalculation(int x) {
return x * x;
}
[[nodiscard]]
constexpr int modernCalculation(int x) noexcept {
return x * x;
}
// Attributes on class members
class AttributeDemo {
public:
[[nodiscard]] bool isReady() const noexcept { return ready_; }
[[deprecated("Use setStatus() instead")]]
void setReady(bool ready) { ready_ = ready; }
void setStatus([[maybe_unused]] bool status) {
ready_ = status;
}
private:
[[maybe_unused]] static constexpr int VERSION = 1;
bool ready_ = false;
};
// Namespace-level attributes
namespace [[deprecated("Use modern_api namespace instead")]] legacy_api {
void oldStyleFunction() {
std::cout << "Legacy API function" << std::endl;
}
}
namespace modern_api {
[[nodiscard]] bool newStyleFunction() {
std::cout << "Modern API function" << std::endl;
return true;
}
}
// Function demonstrating attribute usage patterns
void demonstrateStandardAttributes() {
// Test nodiscard attributes
int result = calculateImportantValue(); // OK
calculateImportantValue(); // Warning: discarding nodiscard return value
std::string data = createImportantString(); // OK
createImportantString(); // Warning: discarding nodiscard return value
// Test maybe_unused
processData(1, "DEBUG"); // Parameters marked maybe_unused
// Test deprecated functions
oldFunction(); // Warning: deprecated
int sum = legacyCalculation(5, 3); // Warning: deprecated with message
LegacyClass legacy; // Warning: deprecated class
int oldVal = legacy.getOldValue(); // Warning: deprecated method
int newVal = legacy.getNewValue(); // OK
// Test fallthrough
std::string switchResult = processSwitch(2);
int charResult = complexSwitch('a');
// Test likely/unlikely
int condResult = processConditions(10); // Likely path
try {
int errorResult = processConditions(-200); // Unlikely path
} catch (const std::runtime_error& e) {
std::cerr << "Caught exception: " << e.what() << std::endl;
}
// Test optional parsing with likelihood
auto parsed1 = parseInput("123"); // Likely success
auto parsed2 = parseInput(""); // Unlikely empty input
auto parsed3 = parseInput("not_number"); // Normal failure case
// Test combined attributes
int legacyResult = legacyImportantCalculation(5); // Deprecated + nodiscard
int modernResult = modernCalculation(5); // Just nodiscard
// Test class attributes
AttributeDemo demo;
bool ready = demo.isReady(); // nodiscard
demo.setReady(true); // deprecated
demo.setStatus(true); // modern method
// Test namespace attributes
legacy_api::oldStyleFunction(); // Deprecated namespace
bool success = modern_api::newStyleFunction(); // Modern namespace
}
// Template with attributes
template<typename T>
[[nodiscard]] constexpr T multiply([[maybe_unused]] T a, T b) noexcept {
// In some specializations, parameter 'a' might not be used
return b * b; // Simplified implementation
}
// Specialization with different attribute usage
template<>
[[nodiscard]] constexpr int multiply<int>(int a, int b) noexcept {
return a * b; // Both parameters used in this specialization
}
void testTemplateAttributes() {
auto intResult = multiply<int>(3, 4); // Uses specialization
auto doubleResult = multiply<double>(2.5, 3.0); // Uses general template
// Test discarding nodiscard return
multiply<int>(5, 6); // Warning: discarding nodiscard return
}
"""
)
parsers, queries = load_parsers()
updater = GraphUpdater(
ingestor=mock_ingestor,
repo_path=cpp_attributes_project,
parsers=parsers,
queries=queries,
)
updater.run()
# Verify function definitions with attributes are tracked
all_relationships = cast(
MagicMock, mock_ingestor.ensure_relationship_batch
).call_args_list
defines_relationships = [c for c in all_relationships if c.args[1] == "DEFINES"]
call_relationships = [c for c in all_relationships if c.args[1] == "CALLS"]
# Functions with attributes should be defined
attributed_functions = [
call
for call in defines_relationships
if "standard_attributes" in call.args[0][2]
and any(
func in call.args[2][2]
for func in [
"calculateImportantValue",
"createImportantString",
"processData",
"oldFunction",
"legacyCalculation",
"processSwitch",
"processConditions",
]
)
]
assert len(attributed_functions) >= 7, (
f"Expected at least 7 attributed functions, found {len(attributed_functions)}"
)
# Function calls should be tracked
attribute_function_calls = [
call
for call in call_relationships
if "standard_attributes" in call.args[0][2]
and any(
func in call.args[2][2]
for func in [
"calculateImportantValue",
"createImportantString",
"oldFunction",
]
)
]
assert len(attribute_function_calls) >= 3, (
f"Expected at least 3 attributed function calls, found {len(attribute_function_calls)}"
)
def test_compiler_specific_attributes(
cpp_attributes_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test compiler-specific attributes and non-standard extensions."""
test_file = cpp_attributes_project / "compiler_attributes.cpp"
test_file.write_text(
"""
#include <iostream>
#include <vector>
#include <string>
// GCC/Clang specific attributes using __attribute__ syntax
__attribute__((always_inline))
inline int fastFunction(int x) {
return x * 2;
}
__attribute__((noinline))
void slowFunction() {
std::cout << "This function should not be inlined" << std::endl;
}
__attribute__((pure))
int pureCalculation(int a, int b) {
// Pure function - no side effects, result depends only on arguments
return a + b * 2;
}
__attribute__((const))
constexpr int constantCalculation(int x) {
// Const function - even stricter than pure, no memory access
return x * x;
}
// Function alignment
__attribute__((aligned(32)))
void alignedFunction() {
std::cout << "Function aligned to 32-byte boundary" << std::endl;
}
// Hot/Cold attributes for optimization
__attribute__((hot))
void frequentlyCalledFunction() {
// This function is called frequently and should be optimized for speed
for (int i = 0; i < 1000; ++i) {
// Tight loop
}
}
__attribute__((cold))
void rarelyCalledFunction() {
// This function is rarely called, optimize for size instead of speed
std::cerr << "Error: This should rarely happen" << std::endl;
}
// Visibility attributes for shared libraries
__attribute__((visibility("default")))
void publicApiFunction() {
std::cout << "This function is part of the public API" << std::endl;
}
__attribute__((visibility("hidden")))
void internalFunction() {
std::cout << "This function is internal to the library" << std::endl;
}
// Constructor/Destructor attributes
__attribute__((constructor))
void moduleInitializer() {
std::cout << "Module constructor called" << std::endl;
}
__attribute__((destructor))
void moduleCleanup() {
std::cout << "Module destructor called" << std::endl;
}
// Variable attributes
__attribute__((aligned(64)))
static int alignedVariable = 42;
__attribute__((section(".special_data")))
static int specialSectionVariable = 100;
__attribute__((weak))
int weakSymbol = 200;
// Weak function that can be overridden
__attribute__((weak))
void weakFunction() {
std::cout << "Default weak implementation" << std::endl;
}
// Warning attributes
__attribute__((deprecated("Use newSecureFunction() instead")))
void insecureFunction(char* buffer) {
// Unsafe string operations
strcpy(buffer, "unsafe");
}
void newSecureFunction(std::string& buffer) {
buffer = "safe";
}
// Format checking attributes
__attribute__((format(printf, 1, 2)))
void debugPrintf(const char* format, ...) {
// Compiler will check printf-style format strings
va_list args;
va_start(args, format);
vprintf(format, args);
va_end(args);
}
// Return value checking
__attribute__((warn_unused_result))
bool criticalOperation() {
// Return value should not be ignored
return true;
}
// Sentinel attribute for variadic functions
__attribute__((sentinel))
void processStrings(const char* first, ...) {
// Last argument must be NULL
va_list args;
va_start(args, first);
const char* current = first;
while (current != nullptr) {
std::cout << current << " ";
current = va_arg(args, const char*);
}
va_end(args);
std::cout << std::endl;
}
// Microsoft Visual C++ specific attributes
#ifdef _MSC_VER
__declspec(noinline)
void msvcNoInline() {
std::cout << "MSVC no-inline function" << std::endl;
}
__declspec(forceinline)
inline void msvcForceInline() {
// Force inlining even if compiler thinks it's not beneficial
}
__declspec(dllexport)
void exportedFunction() {
std::cout << "Function exported from DLL" << std::endl;
}
__declspec(align(16))
struct AlignedStruct {
double data[2];
};
#endif
// Mixed standard and compiler-specific attributes
[[nodiscard]] __attribute__((pure))
int combinedAttributesFunction(int x, int y) {
return x * y;
}
[[deprecated("Use modernCombinedFunction()")]] __attribute__((cold))
void legacyCombinedFunction() {
std::cout << "Legacy function with mixed attributes" << std::endl;
}
// Class with compiler-specific attributes
class __attribute__((packed)) PackedClass {
char a;
int b; // Normally would be aligned, but packed prevents padding
char c;
};
// Attribute on class methods
class AttributedClass {
public:
__attribute__((always_inline))
inline int inlinedMethod() const { return value_; }
__attribute__((noinline))
void nonInlinedMethod() {
value_++;
}
[[nodiscard]] __attribute__((pure))
int pureMethod(int x) const {
return value_ + x;
}
private:
mutable int value_ = 0;
};
// Function demonstrating compiler-specific attribute usage
void demonstrateCompilerAttributes() {
// Test always_inline/noinline
int fast = fastFunction(5);
slowFunction();
// Test pure/const functions
int pureResult = pureCalculation(3, 4);
int constResult = constantCalculation(6);
// Test hot/cold functions
frequentlyCalledFunction(); // Called in hot path
try {
throw std::runtime_error("Test error");
} catch (...) {
rarelyCalledFunction(); // Called in error path (cold)
}
// Test visibility functions
publicApiFunction();
internalFunction();
// Test weak symbols
weakFunction(); // May call overridden version if available
// Test deprecated function
char buffer[100];
insecureFunction(buffer); // Warning: deprecated
std::string secureBuffer;
newSecureFunction(secureBuffer); // Modern alternative
// Test format checking
debugPrintf("Debug value: %d, string: %s\\n", 42, "test");
// Test return value checking
bool result = criticalOperation(); // OK
criticalOperation(); // Warning: unused result
// Test sentinel function
processStrings("first", "second", "third", nullptr); // Must end with nullptr
// Test combined attributes
int combined = combinedAttributesFunction(7, 8); // nodiscard + pure
legacyCombinedFunction(); // deprecated + cold
// Test class attributes
PackedClass packed;
std::cout << "PackedClass size: " << sizeof(PackedClass) << std::endl;
AttributedClass attributed;
int inlined = attributed.inlinedMethod(); // always_inline
attributed.nonInlinedMethod(); // noinline
int pure = attributed.pureMethod(10); // nodiscard + pure
#ifdef _MSC_VER
// Test MSVC-specific attributes
msvcNoInline();
msvcForceInline();
exportedFunction();
AlignedStruct aligned;
std::cout << "AlignedStruct alignment: " << alignof(AlignedStruct) << std::endl;
#endif
}
// Template function with attributes
template<typename T>
__attribute__((always_inline)) [[nodiscard]]
constexpr T attributedTemplate(T value) noexcept {
return value * 2;
}
// Specialization with different attributes
template<>
__attribute__((noinline)) [[nodiscard]]
int attributedTemplate<int>(int value) noexcept {
// Force no-inline for int specialization
return value * 3;
}
void testAttributedTemplates() {
auto floatResult = attributedTemplate<float>(2.5f); // Inlined
auto intResult = attributedTemplate<int>(5); // Not inlined
// Test discarding results
attributedTemplate<double>(3.0); // Warning: nodiscard
}
// Attribute inheritance in class hierarchies
class __attribute__((visibility("default"))) BaseClass {
public:
virtual ~BaseClass() = default;
[[nodiscard]] virtual bool virtualMethod() const = 0;
__attribute__((hot))
void hotMethod() const {
// Frequently called base method
}
};
class DerivedClass : public BaseClass {
public:
[[nodiscard]] bool virtualMethod() const override {
return true;
}
__attribute__((cold))
void coldMethod() const {
// Rarely called derived method
}
};
void testAttributeInheritance() {
DerivedClass derived;
bool result = derived.virtualMethod(); // nodiscard from override
derived.hotMethod(); // Inherited hot method
derived.coldMethod(); // Cold derived method
// Polymorphic call
BaseClass* base = &derived;
bool polyResult = base->virtualMethod(); // Virtual dispatch with nodiscard
base->hotMethod(); // Virtual call to hot method
}
"""
)
parsers, queries = load_parsers()
updater = GraphUpdater(
ingestor=mock_ingestor,
repo_path=cpp_attributes_project,
parsers=parsers,
queries=queries,
)
updater.run()
# Verify compiler-specific attributed functions are tracked
all_relationships = cast(
MagicMock, mock_ingestor.ensure_relationship_batch
).call_args_list
defines_relationships = [c for c in all_relationships if c.args[1] == "DEFINES"]
[c for c in all_relationships if c.args[1] == "CALLS"]
# Functions with compiler-specific attributes should be defined
compiler_attributed_functions = [
call
for call in defines_relationships
if "compiler_attributes" in call.args[0][2]
and any(
func in call.args[2][2]
for func in [
"fastFunction",
"slowFunction",
"pureCalculation",
"constantCalculation",
"frequentlyCalledFunction",
"rarelyCalledFunction",
"publicApiFunction",
]
)
]
assert len(compiler_attributed_functions) >= 6, (
f"Expected at least 6 compiler-attributed functions, found {len(compiler_attributed_functions)}"
)
# Classes with attributes should be tracked
attributed_classes = [
call
for call in defines_relationships
if "compiler_attributes" in call.args[0][2]
and any(
cls in call.args[2][2]
for cls in ["PackedClass", "AttributedClass", "BaseClass", "DerivedClass"]
)
]
assert len(attributed_classes) >= 3, (
f"Expected at least 3 attributed classes, found {len(attributed_classes)}"
)
def test_attribute_combinations_and_edge_cases(
cpp_attributes_project: Path,
mock_ingestor: MagicMock,
) -> None:
"""Test complex attribute combinations and edge cases."""
test_file = cpp_attributes_project / "attribute_edge_cases.cpp"
test_file.write_text(
"""
#include <iostream>
#include <functional>
#include <memory>
#include <type_traits>
// Multiple standard attributes on same declaration
[[nodiscard, deprecated("Use newMultiAttributeFunction() instead"), maybe_unused]]
int multiAttributeFunction(int x) {
return x * 2;
}
// Attributes on different parts of function signature
[[nodiscard]]
auto complexAttributeFunction(
[[maybe_unused]] int param1,
const std::string& param2
) noexcept [[deprecated("Complex signature deprecated")]] -> int {
return static_cast<int>(param2.length());
}
// Attributes in template contexts
template<typename T>
[[nodiscard]] constexpr bool templateWithAttributes(
[[maybe_unused]] T&& value,
[[maybe_unused]] int context = 0
) noexcept {
if constexpr (std::is_integral_v<T>) {
return true;
} else [[likely]] {
return false;
}
}
// Conditional attributes based on compilation context
#ifdef DEBUG
#define DEBUG_DEPRECATED [[deprecated("Debug-only function")]]
#define DEBUG_MAYBE_UNUSED [[maybe_unused]]
#else
#define DEBUG_DEPRECATED
#define DEBUG_MAYBE_UNUSED
#endif
DEBUG_DEPRECATED
void debugOnlyFunction(DEBUG_MAYBE_UNUSED int debugLevel) {
std::cout << "Debug function" << std::endl;
}
// Attributes on lambda expressions
void testLambdaAttributes() {
// Lambda with attributes on parameters
auto lambda1 = [](
[[maybe_unused]] int unused_param,
int used_param
) [[nodiscard]] -> int {
return used_param * 2;
};
// Lambda with attributes on capture
int captured = 42;
auto lambda2 = [captured]
[[deprecated("Use lambda3 instead")]]
[[nodiscard]] (int x) -> int {
return captured + x;
};
// Use lambdas
int result1 = lambda1(0, 5); // maybe_unused param, nodiscard result
int result2 = lambda2(10); // deprecated + nodiscard
lambda1(1, 2); // Warning: discarding nodiscard result
}
// Attributes on structured bindings (C++17)
void testStructuredBindingAttributes() {
std::pair<int, std::string> data{42, "test"};
// Attributes on structured binding declaration
[[maybe_unused]] auto [value, text] = data;
// Only use one binding
std::cout << "Text: " << text << std::endl;
// 'value' is maybe_unused, so no warning
}
// Custom attribute-like macros
#define FORCE_INLINE __attribute__((always_inline)) inline
#define NO_RETURN [[noreturn]]
#define PURE_FUNCTION [[nodiscard]] __attribute__((pure))
FORCE_INLINE
int customInlineFunction(int x) {
return x + 1;
}
NO_RETURN
void terminateProgram() {
std::terminate();
}
PURE_FUNCTION
int customPureFunction(int a, int b) {
return a * b + 1;
}
// Attributes on member function pointers
class AttributePointerTest {
public:
[[nodiscard]] int normalMethod() const { return 42; }
[[deprecated("Use newMethod() instead")]]
void oldMethod() const {}
void newMethod() const {}
};
void testMemberFunctionPointers() {
AttributePointerTest obj;
// Pointer to attributed member function
auto normalPtr = &AttributePointerTest::normalMethod;
auto oldPtr = &AttributePointerTest::oldMethod;
auto newPtr = &AttributePointerTest::newMethod;
// Call through pointers
int result = (obj.*normalPtr)(); // nodiscard
(obj.*oldPtr)(); // deprecated
(obj.*newPtr)(); // normal
// Discard nodiscard result
(obj.*normalPtr)(); // Warning: discarding nodiscard
}
// Attributes on friend functions
class FriendAttributeTest {
friend [[deprecated("Friend function deprecated")]]
void deprecatedFriend(const FriendAttributeTest& obj) {
std::cout << "Deprecated friend: " << obj.value_ << std::endl;
}
friend [[nodiscard]]
bool modernFriend(const FriendAttributeTest& obj) {
return obj.value_ > 0;
}
private:
int value_ = 100;
};
void testFriendAttributes() {
FriendAttributeTest obj;
deprecatedFriend(obj); // Warning: deprecated
bool result = modernFriend(obj); // nodiscard
modernFriend(obj); // Warning: discarding nodiscard
}
// Attributes on type aliases and using declarations
[[deprecated("Use ModernType instead")]]
using LegacyType = int;
using ModernType = int;
[[maybe_unused]]
using OptionalType = std::optional<int>;
// Attributes on variable templates
template<typename T>
[[maybe_unused]] constexpr bool is_special_v = false;
template<>
constexpr bool is_special_v<int> = true;
// Attributes on concepts (C++20)
#if __cpp_concepts >= 201907L
template<typename T>
[[deprecated("Use modern_concept instead")]]
concept legacy_concept = std::is_integral_v<T>;
template<typename T>
concept modern_concept = std::is_arithmetic_v<T>;
#endif
// Function with attributes on exception specification
[[nodiscard]]
int riskyFunction() noexcept(false) [[deprecated("May throw exceptions")]] {
if (rand() % 2) {
throw std::runtime_error("Random error");
}
return 42;
}
// Nested attribute scenarios
namespace [[deprecated("Legacy namespace")]] legacy {
[[deprecated("Nested deprecated function")]]
void nestedDeprecated() {
std::cout << "Doubly deprecated" << std::endl;
}
class [[deprecated("Nested deprecated class")]] NestedClass {
public:
[[deprecated("Triply nested deprecated method")]]
void method() const {
std::cout << "Triply deprecated" << std::endl;
}
};
}
// Comprehensive demonstration function
void demonstrateAttributeEdgeCases() {
// Test multi-attribute function
int multi = multiAttributeFunction(5); // deprecated + nodiscard
multiAttributeFunction(10); // Warning: discarding nodiscard
// Test complex signature attributes
int complex = complexAttributeFunction(0, "test"); // deprecated + nodiscard
// Test template attributes
bool intResult = templateWithAttributes(42); // likely branch
bool stringResult = templateWithAttributes(std::string("test")); // unlikely branch
// Test debug attributes
debugOnlyFunction(3); // May be deprecated in debug builds
// Test lambda attributes
testLambdaAttributes();
// Test structured bindings
testStructuredBindingAttributes();
// Test custom attribute macros
int inlined = customInlineFunction(5);
int pure = customPureFunction(3, 4);
// terminateProgram(); // Would terminate - commented out
// Test member function pointer attributes
testMemberFunctionPointers();
// Test friend function attributes
testFriendAttributes();
// Test type alias attributes