/*

* Cppcheck - A tool for static C/C++ code analysis

* Copyright (C) 2007-2022 Cppcheck team.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

*

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License

* along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

#include "checkclass.h"

#include "errortypes.h"

#include "platform.h"

#include "settings.h"

#include "testsuite.h"

#include "tokenize.h"

#include <map>

#include <sstream> // IWYU pragma: keep

#include <string>

#include <utility>

#include <vector>

#include <simplecpp.h>

class TestUnusedPrivateFunction : public TestFixture {

public:

TestUnusedPrivateFunction() : TestFixture("TestUnusedPrivateFunction") {}

private:

Settings settings;

void run() override {

settings.severity.enable(Severity::style);

TEST_CASE(test1);

TEST_CASE(test2);

TEST_CASE(test3);

TEST_CASE(test4);

TEST_CASE(test5);

TEST_CASE(test6); // ticket #2602

TEST_CASE(test7); // ticket #9282

// [ 2236547 ] False positive --style unused function, called via pointer

TEST_CASE(func_pointer1);

TEST_CASE(func_pointer2);

TEST_CASE(func_pointer3);

TEST_CASE(func_pointer4); // ticket #2807

TEST_CASE(func_pointer5); // ticket #2233

TEST_CASE(func_pointer6); // ticket #4787

TEST_CASE(func_pointer7); // ticket #10516

TEST_CASE(ctor);

TEST_CASE(ctor2);

TEST_CASE(classInClass);

TEST_CASE(sameFunctionNames);

TEST_CASE(incompleteImplementation);

TEST_CASE(derivedClass); // skip warning for derived classes. It might be a virtual function.

TEST_CASE(friendClass);

TEST_CASE(borland1); // skip FP when using __property

TEST_CASE(borland2); // skip FP when using __published

// No false positives when there are "unused" templates that are removed in the simplified token list

TEST_CASE(template1);

// #2407 - FP when called from operator()

TEST_CASE(fp_operator);

TEST_CASE(testDoesNotIdentifyMethodAsFirstFunctionArgument); // #2480

TEST_CASE(testDoesNotIdentifyMethodAsMiddleFunctionArgument);

TEST_CASE(testDoesNotIdentifyMethodAsLastFunctionArgument);

TEST_CASE(multiFile);

TEST_CASE(unknownBaseTemplate); // ticket #2580

TEST_CASE(hierarchy_loop); // ticket 5590

TEST_CASE(staticVariable); //ticket #5566

TEST_CASE(templateSimplification); //ticket #6183

TEST_CASE(maybeUnused);

}

void check(const char code[], Settings::PlatformType platform = Settings::Native) {

// Clear the error buffer..

errout.str("");

settings.platform(platform);

// Raw tokens..

std::vector<std::string> files(1, "test.cpp");

std::istringstream istr(code);

const simplecpp::TokenList tokens1(istr, files, files[0]);

// Preprocess..

simplecpp::TokenList tokens2(files);

std::map<std::string, simplecpp::TokenList*> filedata;

simplecpp::preprocess(tokens2, tokens1, files, filedata, simplecpp::DUI());

// Tokenize..

Tokenizer tokenizer(&settings, this);

tokenizer.createTokens(std::move(tokens2));

tokenizer.simplifyTokens1("");

// Check for unused private functions..

CheckClass checkClass(&tokenizer, &settings, this);

checkClass.privateFunctions();

}

void test1() {

check("class Fred\n"

"{\n"

"private:\n"

" unsigned int f();\n"

"public:\n"

" Fred();\n"

"};\n"

"\n"

"Fred::Fred()\n"

"{ }\n"

"\n"

"unsigned int Fred::f()\n"

"{ }");

ASSERT_EQUALS("[test.cpp:4]: (style) Unused private function: 'Fred::f'\n", errout.str());

check("#line 1 \"p.h\"\n"

"class Fred\n"

"{\n"

"private:\n"

" unsigned int f();\n"

"public:\n"

" Fred();\n"

"};\n"

"\n"

"#line 1 \"p.cpp\"\n"

"Fred::Fred()\n"

"{ }\n"

"\n"

"unsigned int Fred::f()\n"

"{ }");

ASSERT_EQUALS("[p.h:4]: (style) Unused private function: 'Fred::f'\n", errout.str());

check("#line 1 \"p.h\"\n"

"class Fred\n"

"{\n"

"private:\n"

"void f();\n"

"};\n"

"\n"

"\n"

"#line 1 \"p.cpp\"\n"

"\n"

"void Fred::f()\n"

"{\n"

"}");

ASSERT_EQUALS("[p.h:4]: (style) Unused private function: 'Fred::f'\n", errout.str());

// Don't warn about include files which implementation we don't see

check("#line 1 \"p.h\"\n"

"class Fred\n"

"{\n"

"private:\n"

"void f();\n"

"void g() {}\n"

"};\n"

"\n"

"#line 1 \"p.cpp\"\n"

"\n"

"int main()\n"

"{\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void test2() {

check("class A {\n"

"public:\n"

" A();\n"

"\n"

" void a() const\n"

" { b(); }\n"

"private:\n"

" void b( ) const\n"

" { }\n"

"};\n"

"\n"

"A::A()\n"

"{ }");

ASSERT_EQUALS("", errout.str());

}

void test3() {

check("class A {\n"

"public:\n"

" A() { }\n"

" ~A();\n"

"private:\n"

" void B() { }\n"

"};\n"

"\n"

"A::~A()\n"

"{ B(); }");

ASSERT_EQUALS("", errout.str());

}

void test4() {

check("class A {\n"

"public:\n"

" A();\n"

"private:\n"

" bool _owner;\n"

" void b() { }\n"

"};\n"

"\n"

"A::A() : _owner(false)\n"

"{ b(); }");

ASSERT_EQUALS("", errout.str());

}

void test5() {

check("class A {\n"

"private:\n"

" A() : lock(new Lock())\n"

" { }\n"

" Lock *lock;\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void test6() { // ticket #2602 segmentation fault

check("class A {\n"

" A& operator=(const A&);\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void test7() { // ticket #9282

check("class C {\n"

" double f1() const noexcept, f2(double) const noexcept;\n"

" void f3() const noexcept;\n"

"};\n"

"double C::f1() const noexcept { f3(); }\n"

"void C::f3() const noexcept {}\n");

ASSERT_EQUALS("", errout.str());

}

void func_pointer1() {

check("class Fred\n"

"{\n"

"private:\n"

" typedef void (*testfp)();\n"

"\n"

" testfp get()\n"

" {\n"

" return test;\n"

" }\n"

"\n"

" static void test()\n"

" { }\n"

"\n"

"public:\n"

" Fred();\n"

"};\n"

"\n"

"Fred::Fred()\n"

"{}");

ASSERT_EQUALS("[test.cpp:6]: (style) Unused private function: 'Fred::get'\n", errout.str());

}

void func_pointer2() {

check("class UnusedPrivateFunctionMemberPointer\n"

"{\n"

"public:\n"

" UnusedPrivateFunctionMemberPointer()\n"

" : mObserver(this, &UnusedPrivateFunctionMemberPointer::callback)\n"

" {}\n"

"\n"

"private:\n"

" void callback(const& unsigned) const {}\n"

"\n"

" Observer<UnusedPrivateFunctionMemberPointer, unsigned> mObserver;\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void func_pointer3() {

check("class c1\n"

"{\n"

"public:\n"

" c1()\n"

" { sigc::mem_fun(this, &c1::f1); }\n"

"\n"

"private:\n"

" void f1() const {}\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void func_pointer4() { // ticket #2807

check("class myclass {\n"

"public:\n"

" myclass();\n"

"private:\n"

" static void f();\n"

" void (*fptr)();\n"

"};\n"

"myclass::myclass() { fptr = &f; }\n"

"void myclass::f() {}");

ASSERT_EQUALS("", errout.str());

}

void func_pointer5() {

check("class A {\n"

"public:\n"

" A() { f = A::func; }\n"

" void (*f)();\n"

"private:\n"

" static void func() { }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void func_pointer6() { // #4787

check("class Test {\n"

"private:\n"

" static void a(const char* p) { }\n"

"public:\n"

" void test(void* f = a) {\n"

" f(\"test\");\n"

" }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void func_pointer7() { // #10516

check("class C {\n"

" static void f() {}\n"

" static constexpr void(*p)() = f;\n"

"};\n");

ASSERT_EQUALS("", errout.str());

check("class C {\n"

" static void f() {}\n"

" static constexpr void(*p)() = &f;\n"

"};\n");

ASSERT_EQUALS("", errout.str());

check("class C {\n"

" static void f() {}\n"

" static constexpr void(*p)() = C::f;\n"

"};\n");

ASSERT_EQUALS("", errout.str());

check("class C {\n"

" static void f() {}\n"

" static constexpr void(*p)() = &C::f;\n"

"};\n");

ASSERT_EQUALS("", errout.str());

}

void ctor() {

check("class PrivateCtor\n"

"{\n"

"private:\n"

" PrivateCtor(int threadNum) :\n"

" numOfThreads(threadNum)\n"

" {\n"

" }\n"

"\n"

" int numOfThreads;\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void ctor2() {

check("struct State {\n"

" State(double const totalWeighting= TotalWeighting()) :\n"

" totalWeighting_(totalWeighting) {}\n"

"private:\n"

" double TotalWeighting() { return 123.0; }\n" // called from constructor

"public:\n"

" double totalWeighting_;\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void classInClass() {

check("class A\n"

"{\n"

"public:\n"

"\n"

" class B\n"

" {\n"

" private:\n"

" };\n"

"private:\n"

" static void f()\n"

" { }\n"

"};");

ASSERT_EQUALS("[test.cpp:10]: (style) Unused private function: 'A::f'\n", errout.str());

check("class A\n"

"{\n"

"public:\n"

" A()\n"

" { }\n"

"\n"

"private:\n"

" void f()\n"

" { }\n"

"\n"

" class B\n"

" {\n"

" public:\n"

" B(A *a)\n"

" { a->f(); }\n"

" };\n"

"};");

ASSERT_EQUALS("", errout.str());

check("class A {\n" // #6968 - outer definition

"public:\n"

" class B;\n"

"private:\n"

" void f() {}\n"

"}\n"

"class A::B {"

" B() { A a; a.f(); }\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void sameFunctionNames() {

check("class A\n"

"{\n"

"public:\n"

" void a()\n"

" {\n"

" f(1);\n"

" }\n"

"\n"

"private:\n"

" void f() { }\n"

" void f(int) { }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void incompleteImplementation() {

// The implementation for "A::a" is missing - so don't check if

// "A::b" is used or not

check("#file \"test.h\"\n"

"class A\n"

"{\n"

"public:\n"

" A();\n"

" void a();\n"

"private:\n"

" void b();\n"

"};\n"

"#endfile\n"

"A::A() { }\n"

"void A::b() { }");

ASSERT_EQUALS("", errout.str());

}

void derivedClass() {

// skip warning in derived classes in case the base class is invisible

check("class derived : public base\n"

"{\n"

"public:\n"

" derived() : base() { }\n"

"private:\n"

" void f();\n"

"};");

ASSERT_EQUALS("", errout.str());

check("class base {\n"

"public:\n"

" virtual void foo();\n"

" void bar();\n"

"};\n"

"class derived : public base {\n"

"private:\n"

" void foo() {}\n" // Skip for overrides of virtual functions of base

" void bar() {}\n" // Don't skip if no function is overridden

"};");

ASSERT_EQUALS("[test.cpp:9]: (style) Unused private function: 'derived::bar'\n", errout.str());

check("class Base {\n"

"private:\n"

" virtual void func() = 0;\n"

"public:\n"

" void public_func() {\n"

" func();\n"

" };\n"

"};\n"

"\n"

"class Derived1: public Base {\n"

"private:\n"

" void func() {}\n"

"};\n"

"class Derived2: public Derived1 {\n"

"private:\n"

" void func() {}\n"

"};");

ASSERT_EQUALS("", errout.str());

check("class Base {\n"

"public:\n"

" void dostuff() {\n"

" f();\n"

" }\n"

"\n"

"private:\n"

" virtual Base* f() = 0;\n"

"};\n"

"\n"

"class Derived : public Base {\n"

"private:\n"

" Derived* f() {\n"

" return 0;\n"

" }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void friendClass() {

// ticket #2459 - friend class

check("class Foo {\n"

"private:\n"

" friend Bar;\n" // Unknown friend class

" void f() { }\n"

"};");

ASSERT_EQUALS("", errout.str());

check("struct Bar {\n"

" void g() { f(); }\n" // Friend class seen, but f not seen

"};\n"

"class Foo {\n"

"private:\n"

" friend Bar;\n"

" void f();\n"

"};");

ASSERT_EQUALS("", errout.str());

check("struct Bar {\n"

" void g() { f(); }\n" // Friend class seen, but f() used in it

"};\n"

"class Foo {\n"

"private:\n"

" friend Bar;\n"

" void f() { }\n"

"};");

ASSERT_EQUALS("", errout.str());

check("class Bar {\n" // Friend class seen, f() not used in it

"};\n"

"class Foo {\n"

" friend Bar;\n"

" void f() { }\n"

"};");

ASSERT_EQUALS("[test.cpp:5]: (style) Unused private function: 'Foo::f'\n", errout.str());

check("struct F;\n" // #10265

"struct S {\n"

" int i{};\n"

" friend struct F;\n"

"private:\n"

" int f() const { return i; }\n"

"};\n"

"struct F {\n"

" bool operator()(const S& lhs, const S& rhs) const {\n"

" return lhs.f() < rhs.f();\n"

" }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void borland1() {

// ticket #2034 - Borland C++ __property

check("class Foo {\n"

"private:\n"

" int getx() {\n"

" return 123;\n"

" }\n"

"public:\n"

" Foo() { }\n"

" __property int x = {read=getx}\n"

"};", Settings::Win32A);

ASSERT_EQUALS("", errout.str());

}

void borland2() {

// ticket #3661 - Borland C++ __published

check("class Foo {\n"

"__published:\n"

" int getx() {\n"

" return 123;\n"

" }\n"

"public:\n"

" Foo() { }\n"

"};", Settings::Win32A);

ASSERT_EQUALS("", errout.str());

}

void template1() {

// ticket #2067 - Template methods do not "use" private ones

check("class A {\n"

"public:\n"

" template <class T>\n"

" T getVal() const;\n"

"\n"

"private:\n"

" int internalGetVal() const { return 8000; }\n"

"};\n"

"\n"

"template <class T>\n"

"T A::getVal() const {\n"

" return internalGetVal();\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void fp_operator() {

// #2407 - FP when function is called from operator()

check("class Fred\n"

"{\n"

"public:\n"

" void operator()(int x) {\n"

" startListening();\n"

" }\n"

"\n"

"private:\n"

" void startListening() {\n"

" }\n"

"};");

ASSERT_EQUALS("", errout.str());

check("class Fred\n"

"{\n"

"public:\n"

" void operator()(int x) {\n"

" }\n"

"\n"

"private:\n"

" void startListening() {\n"

" }\n"

"};");

ASSERT_EQUALS("[test.cpp:8]: (style) Unused private function: 'Fred::startListening'\n", errout.str());

// #5059

check("class Fred {\n"

" void* operator new(size_t obj_size, size_t buf_size) {}\n"

"};");

TODO_ASSERT_EQUALS("[test.cpp:2]: (style) Unused private function: 'Fred::operatornew'\n", "", errout.str()); // No message for operators - we currently cannot check their usage

check("class Fred {\n"

" void* operator new(size_t obj_size, size_t buf_size) {}\n"

"public:\n"

" void* foo() { return new(size) Fred(); }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

void testDoesNotIdentifyMethodAsFirstFunctionArgument() {

check("void callback(void (*func)(int), int arg)"

"{"

" (*func)(arg);"

"}"

"class MountOperation"

"{"

" static void Completed(int i);"

"public:"

" MountOperation(int i);"

"};"

"void MountOperation::Completed(int i)"

"{"

" std::cerr << i << std::endl;"

"}"

"MountOperation::MountOperation(int i)"

"{"

" callback(MountOperation::Completed, i);"

"}"

"int main(void)"

"{"

" MountOperation aExample(10);"

"}"

);

ASSERT_EQUALS("", errout.str());

}

void testDoesNotIdentifyMethodAsMiddleFunctionArgument() {

check("void callback(char, void (*func)(int), int arg)"

"{"

" (*func)(arg);"

"}"

"class MountOperation"

"{"

" static void Completed(int i);"

"public:"

" MountOperation(int i);"

"};"

"void MountOperation::Completed(int i)"

"{"

" std::cerr << i << std::endl;"

"}"

"MountOperation::MountOperation(int i)"

"{"

" callback('a', MountOperation::Completed, i);"

"}"

"int main(void)"

"{"

" MountOperation aExample(10);"

"}"

);

ASSERT_EQUALS("", errout.str());

}

void testDoesNotIdentifyMethodAsLastFunctionArgument() {

check("void callback(int arg, void (*func)(int))"

"{"

" (*func)(arg);"

"}"

"class MountOperation"

"{"

" static void Completed(int i);"

"public:"

" MountOperation(int i);"

"};"

"void MountOperation::Completed(int i)"

"{"

" std::cerr << i << std::endl;"

"}"

"MountOperation::MountOperation(int i)"

"{"

" callback(i, MountOperation::Completed);"

"}"

"int main(void)"

"{"

" MountOperation aExample(10);"

"}"

);

ASSERT_EQUALS("", errout.str());

}

void multiFile() { // ticket #2567

check("#file \"test.h\"\n"

"struct Fred\n"

"{\n"

" Fred()\n"

" {\n"

" Init();\n"

" }\n"

"private:\n"

" void Init();\n"

"};\n"

"#endfile\n"

"void Fred::Init()\n"

"{\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void unknownBaseTemplate() { // ticket #2580

check("class Bla : public Base2<Base> {\n"

"public:\n"

" Bla() {}\n"

"private:\n"

" virtual void F() const;\n"

"};\n"

"void Bla::F() const { }");

ASSERT_EQUALS("", errout.str());

}

void hierarchy_loop() {

check("class InfiniteB : InfiniteA {\n"

" class D {\n"

" };\n"

"};\n"

"namespace N {\n"

" class InfiniteA : InfiniteB {\n"

" };\n"

"}\n"

"class InfiniteA : InfiniteB {\n"

" void foo();\n"

"};\n"

"void InfiniteA::foo() {\n"

" C a;\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void staticVariable() {

check("class Foo {\n"

" static int i;\n"

" static int F() const { return 1; }\n"

"};\n"

"int Foo::i = Foo::F();");

ASSERT_EQUALS("", errout.str());

check("class Foo {\n"

" static int i;\n"

" int F() const { return 1; }\n"

"};\n"

"Foo f;\n"

"int Foo::i = f.F();");

ASSERT_EQUALS("", errout.str());

check("class Foo {\n"

" static int i;\n"

" static int F() const { return 1; }\n"

"};\n"

"int Foo::i = sth();"

"int i = F();");

ASSERT_EQUALS("[test.cpp:3]: (style) Unused private function: 'Foo::F'\n", errout.str());

}

void templateSimplification() { //ticket #6183

check("class CTest {\n"

"public:\n"

" template <typename T>\n"

" static void Greeting(T val) {\n"

" std::cout << val << std::endl;\n"

" }\n"

"private:\n"

" static void SayHello() {\n"

" std::cout << \"Hello World!\" << std::endl;\n"

" }\n"

"};\n"

"template<>\n"

"void CTest::Greeting(bool) {\n"

" CTest::SayHello();\n"

"}\n"

"int main() {\n"

" CTest::Greeting<bool>(true);\n"

" return 0;\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void maybeUnused() {

check("class C {\n"

" [[maybe_unused]] int f() { return 42; }\n"

"};");

ASSERT_EQUALS("", errout.str());

}

};

REGISTER_TEST(TestUnusedPrivateFunction)