llvm-project/clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-val...

384 lines
14 KiB
C++

// RUN: %check_clang_tidy %s performance-unnecessary-value-param %t
// CHECK-FIXES: #include <utility>
struct ExpensiveToCopyType {
const ExpensiveToCopyType & constReference() const {
return *this;
}
void nonConstMethod();
virtual ~ExpensiveToCopyType();
};
void mutate(ExpensiveToCopyType &);
void mutate(ExpensiveToCopyType *);
void useAsConstReference(const ExpensiveToCopyType &);
void useByValue(ExpensiveToCopyType);
template <class T> class Vector {
public:
using iterator = T*;
using const_iterator = const T*;
Vector(const Vector&);
Vector& operator=(const Vector&);
iterator begin();
iterator end();
const_iterator begin() const;
const_iterator end() const;
};
// This class simulates std::pair<>. It is trivially copy constructible
// and trivially destructible, but not trivially copy assignable.
class SomewhatTrivial {
public:
SomewhatTrivial();
SomewhatTrivial(const SomewhatTrivial&) = default;
~SomewhatTrivial() = default;
SomewhatTrivial& operator=(const SomewhatTrivial&);
};
struct MoveOnlyType {
MoveOnlyType(const MoveOnlyType &) = delete;
MoveOnlyType(MoveOnlyType &&) = default;
~MoveOnlyType();
void constMethod() const;
};
struct ExpensiveMovableType {
ExpensiveMovableType();
ExpensiveMovableType(ExpensiveMovableType &&);
ExpensiveMovableType(const ExpensiveMovableType &) = default;
ExpensiveMovableType &operator=(const ExpensiveMovableType &) = default;
ExpensiveMovableType &operator=(ExpensiveMovableType &&);
~ExpensiveMovableType();
};
void positiveExpensiveConstValue(const ExpensiveToCopyType Obj);
// CHECK-FIXES: void positiveExpensiveConstValue(const ExpensiveToCopyType& Obj);
void positiveExpensiveConstValue(const ExpensiveToCopyType Obj) {
// CHECK-MESSAGES: [[@LINE-1]]:60: warning: the const qualified parameter 'Obj' is copied for each invocation; consider making it a reference [performance-unnecessary-value-param]
// CHECK-FIXES: void positiveExpensiveConstValue(const ExpensiveToCopyType& Obj) {
}
void positiveExpensiveValue(ExpensiveToCopyType Obj);
// CHECK-FIXES: void positiveExpensiveValue(const ExpensiveToCopyType& Obj);
void positiveExpensiveValue(ExpensiveToCopyType Obj) {
// CHECK-MESSAGES: [[@LINE-1]]:49: warning: the parameter 'Obj' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
// CHECK-FIXES: void positiveExpensiveValue(const ExpensiveToCopyType& Obj) {
Obj.constReference();
useAsConstReference(Obj);
auto Copy = Obj;
useByValue(Obj);
}
void positiveVector(Vector<ExpensiveToCopyType> V) {
// CHECK-MESSAGES: [[@LINE-1]]:49: warning: the parameter 'V' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
// CHECK-FIXES: void positiveVector(const Vector<ExpensiveToCopyType>& V) {
for (const auto& Obj : V) {
useByValue(Obj);
}
}
void positiveWithComment(const ExpensiveToCopyType /* important */ S);
// CHECK-FIXES: void positiveWithComment(const ExpensiveToCopyType& /* important */ S);
void positiveWithComment(const ExpensiveToCopyType /* important */ S) {
// CHECK-MESSAGES: [[@LINE-1]]:68: warning: the const qualified
// CHECK-FIXES: void positiveWithComment(const ExpensiveToCopyType& /* important */ S) {
}
void positiveUnnamedParam(const ExpensiveToCopyType) {
// CHECK-MESSAGES: [[@LINE-1]]:52: warning: the const qualified parameter #1
// CHECK-FIXES: void positiveUnnamedParam(const ExpensiveToCopyType&) {
}
void positiveAndNegative(const ExpensiveToCopyType ConstCopy, const ExpensiveToCopyType& ConstRef, ExpensiveToCopyType Copy);
// CHECK-FIXES: void positiveAndNegative(const ExpensiveToCopyType& ConstCopy, const ExpensiveToCopyType& ConstRef, const ExpensiveToCopyType& Copy);
void positiveAndNegative(const ExpensiveToCopyType ConstCopy, const ExpensiveToCopyType& ConstRef, ExpensiveToCopyType Copy) {
// CHECK-MESSAGES: [[@LINE-1]]:52: warning: the const qualified parameter 'ConstCopy'
// CHECK-MESSAGES: [[@LINE-2]]:120: warning: the parameter 'Copy'
// CHECK-FIXES: void positiveAndNegative(const ExpensiveToCopyType& ConstCopy, const ExpensiveToCopyType& ConstRef, const ExpensiveToCopyType& Copy) {
}
struct PositiveConstValueConstructor {
PositiveConstValueConstructor(const ExpensiveToCopyType ConstCopy) {}
// CHECK-MESSAGES: [[@LINE-1]]:59: warning: the const qualified parameter 'ConstCopy'
// CHECK-FIXES: PositiveConstValueConstructor(const ExpensiveToCopyType& ConstCopy) {}
};
template <typename T> void templateWithNonTemplatizedParameter(const ExpensiveToCopyType S, T V) {
// CHECK-MESSAGES: [[@LINE-1]]:90: warning: the const qualified parameter 'S'
// CHECK-FIXES: template <typename T> void templateWithNonTemplatizedParameter(const ExpensiveToCopyType& S, T V) {
}
void instantiated() {
templateWithNonTemplatizedParameter(ExpensiveToCopyType(), ExpensiveToCopyType());
templateWithNonTemplatizedParameter(ExpensiveToCopyType(), 5);
}
template <typename T> void negativeTemplateType(const T V) {
}
void negativeArray(const ExpensiveToCopyType[]) {
}
void negativePointer(ExpensiveToCopyType* Obj) {
}
void negativeConstPointer(const ExpensiveToCopyType* Obj) {
}
void negativeConstReference(const ExpensiveToCopyType& Obj) {
}
void negativeReference(ExpensiveToCopyType& Obj) {
}
void negativeUniversalReference(ExpensiveToCopyType&& Obj) {
}
void negativeSomewhatTrivialConstValue(const SomewhatTrivial Somewhat) {
}
void negativeSomewhatTrivialValue(SomewhatTrivial Somewhat) {
}
void negativeConstBuiltIn(const int I) {
}
void negativeValueBuiltIn(int I) {
}
void negativeValueIsMutatedByReference(ExpensiveToCopyType Obj) {
mutate(Obj);
}
void negativeValueIsMutatatedByPointer(ExpensiveToCopyType Obj) {
mutate(&Obj);
}
void negativeValueIsReassigned(ExpensiveToCopyType Obj) {
Obj = ExpensiveToCopyType();
}
void negativeValueNonConstMethodIsCalled(ExpensiveToCopyType Obj) {
Obj.nonConstMethod();
}
struct PositiveValueUnusedConstructor {
PositiveValueUnusedConstructor(ExpensiveToCopyType Copy) {}
// CHECK-MESSAGES: [[@LINE-1]]:54: warning: the parameter 'Copy'
// CHECK-FIXES: PositiveValueUnusedConstructor(const ExpensiveToCopyType& Copy) {}
};
struct PositiveValueCopiedConstructor {
PositiveValueCopiedConstructor(ExpensiveToCopyType Copy) : Field(Copy) {}
// CHECK-MESSAGES: [[@LINE-1]]:54: warning: the parameter 'Copy'
// CHECK-FIXES: PositiveValueCopiedConstructor(const ExpensiveToCopyType& Copy) : Field(Copy) {}
ExpensiveToCopyType Field;
};
struct PositiveValueMovableConstructor {
PositiveValueMovableConstructor(ExpensiveMovableType Copy) : Field(Copy) {}
// CHECK-MESSAGES: [[@LINE-1]]:70: warning: parameter 'Copy'
// CHECK-FIXES: PositiveValueMovableConstructor(ExpensiveMovableType Copy) : Field(std::move(Copy)) {}
ExpensiveMovableType Field;
};
struct NegativeValueMovedConstructor {
NegativeValueMovedConstructor(ExpensiveMovableType Copy) : Field(static_cast<ExpensiveMovableType &&>(Copy)) {}
ExpensiveMovableType Field;
};
template <typename T>
struct Container {
typedef const T & const_reference;
};
void NegativeTypedefParam(const Container<ExpensiveToCopyType>::const_reference Param) {
}
#define UNNECESSARY_VALUE_PARAM_IN_MACRO_BODY() \
void inMacro(const ExpensiveToCopyType T) { \
} \
// Ensure fix is not applied.
// CHECK-FIXES: void inMacro(const ExpensiveToCopyType T) {
UNNECESSARY_VALUE_PARAM_IN_MACRO_BODY()
// CHECK-MESSAGES: [[@LINE-1]]:1: warning: the const qualified parameter 'T'
#define UNNECESSARY_VALUE_PARAM_IN_MACRO_ARGUMENT(ARGUMENT) \
ARGUMENT
UNNECESSARY_VALUE_PARAM_IN_MACRO_ARGUMENT(void inMacroArgument(const ExpensiveToCopyType InMacroArg) {})
// CHECK-MESSAGES: [[@LINE-1]]:90: warning: the const qualified parameter 'InMacroArg'
// CHECK-FIXES: void inMacroArgument(const ExpensiveToCopyType InMacroArg) {}
struct VirtualMethod {
virtual ~VirtualMethod() {}
virtual void handle(ExpensiveToCopyType T) const = 0;
};
struct NegativeOverriddenMethod : public VirtualMethod {
void handle(ExpensiveToCopyType Overridden) const {
// CHECK-FIXES: handle(ExpensiveToCopyType Overridden) const {
}
};
struct VirtualMethodWarningOnly {
virtual void methodWithExpensiveValueParam(ExpensiveToCopyType T) {}
// CHECK-MESSAGES: [[@LINE-1]]:66: warning: the parameter 'T' is copied
// CHECK-FIXES: virtual void methodWithExpensiveValueParam(ExpensiveToCopyType T) {}
virtual ~VirtualMethodWarningOnly() {}
};
struct PositiveNonVirualMethod {
void method(const ExpensiveToCopyType T) {}
// CHECK-MESSAGES: [[@LINE-1]]:41: warning: the const qualified parameter 'T' is copied
// CHECK-FIXES: void method(const ExpensiveToCopyType& T) {}
};
struct NegativeDeletedMethod {
~NegativeDeletedMethod() {}
NegativeDeletedMethod& operator=(NegativeDeletedMethod N) = delete;
// CHECK-FIXES: NegativeDeletedMethod& operator=(NegativeDeletedMethod N) = delete;
};
void NegativeMoveOnlyTypePassedByValue(MoveOnlyType M) {
M.constMethod();
}
void PositiveMoveOnCopyConstruction(ExpensiveMovableType E) {
auto F = E;
// CHECK-MESSAGES: [[@LINE-1]]:12: warning: parameter 'E' is passed by value and only copied once; consider moving it to avoid unnecessary copies [performance-unnecessary-value-param]
// CHECK-FIXES: auto F = std::move(E);
}
void PositiveConstRefNotMoveSinceReferencedMultipleTimes(ExpensiveMovableType E) {
// CHECK-MESSAGES: [[@LINE-1]]:79: warning: the parameter 'E' is copied
// CHECK-FIXES: void PositiveConstRefNotMoveSinceReferencedMultipleTimes(const ExpensiveMovableType& E) {
auto F = E;
auto G = E;
}
void PositiveMoveOnCopyAssignment(ExpensiveMovableType E) {
ExpensiveMovableType F;
F = E;
// CHECK-MESSAGES: [[@LINE-1]]:7: warning: parameter 'E' is passed by value
// CHECK-FIXES: F = std::move(E);
}
struct NotCopyAssigned {
NotCopyAssigned &operator=(const ExpensiveMovableType &);
};
void PositiveNoMoveForNonCopyAssigmentOperator(ExpensiveMovableType E) {
// CHECK-MESSAGES: [[@LINE-1]]:69: warning: the parameter 'E' is copied
// CHECK-FIXES: void PositiveNoMoveForNonCopyAssigmentOperator(const ExpensiveMovableType& E) {
NotCopyAssigned N;
N = E;
}
// The argument could be moved but is not since copy statement is inside a loop.
void PositiveNoMoveInsideLoop(ExpensiveMovableType E) {
// CHECK-MESSAGES: [[@LINE-1]]:52: warning: the parameter 'E' is copied
// CHECK-FIXES: void PositiveNoMoveInsideLoop(const ExpensiveMovableType& E) {
for (;;) {
auto F = E;
}
}
void PositiveConstRefNotMoveConstructible(ExpensiveToCopyType T) {
// CHECK-MESSAGES: [[@LINE-1]]:63: warning: the parameter 'T' is copied
// CHECK-FIXES: void PositiveConstRefNotMoveConstructible(const ExpensiveToCopyType& T) {
auto U = T;
}
void PositiveConstRefNotMoveAssignable(ExpensiveToCopyType A) {
// CHECK-MESSAGES: [[@LINE-1]]:60: warning: the parameter 'A' is copied
// CHECK-FIXES: void PositiveConstRefNotMoveAssignable(const ExpensiveToCopyType& A) {
ExpensiveToCopyType B;
B = A;
}
// Case where parameter in declaration is already const-qualified but not in
// implementation. Make sure a second 'const' is not added to the declaration.
void PositiveConstDeclaration(const ExpensiveToCopyType A);
// CHECK-FIXES: void PositiveConstDeclaration(const ExpensiveToCopyType& A);
void PositiveConstDeclaration(ExpensiveToCopyType A) {
// CHECK-MESSAGES: [[@LINE-1]]:51: warning: the parameter 'A' is copied
// CHECK-FIXES: void PositiveConstDeclaration(const ExpensiveToCopyType& A) {
}
void PositiveNonConstDeclaration(ExpensiveToCopyType A);
// CHECK-FIXES: void PositiveNonConstDeclaration(const ExpensiveToCopyType& A);
void PositiveNonConstDeclaration(const ExpensiveToCopyType A) {
// CHECK-MESSAGES: [[@LINE-1]]:60: warning: the const qualified parameter 'A'
// CHECK-FIXES: void PositiveNonConstDeclaration(const ExpensiveToCopyType& A) {
}
void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) {
// CHECK-MESSAGES: [[@LINE-1]]:75: warning: the parameter 'A' is copied
// CHECK-FIXES: void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) {
}
void ReferenceFunctionOutsideOfCallExpr() {
void (*ptr)(ExpensiveToCopyType) = &PositiveOnlyMessageAsReferencedInCompilationUnit;
}
void PositiveMessageAndFixAsFunctionIsCalled(ExpensiveToCopyType A) {
// CHECK-MESSAGES: [[@LINE-1]]:66: warning: the parameter 'A' is copied
// CHECK-FIXES: void PositiveMessageAndFixAsFunctionIsCalled(const ExpensiveToCopyType& A) {
}
void ReferenceFunctionByCallingIt() {
PositiveMessageAndFixAsFunctionIsCalled(ExpensiveToCopyType());
}
// Virtual method overrides of dependent types cannot be recognized unless they
// are marked as override or final. Test that check is not triggered on methods
// marked with override or final.
template <typename T>
struct NegativeDependentTypeInterface {
virtual void Method(ExpensiveToCopyType E) = 0;
};
template <typename T>
struct NegativeOverrideImpl : public NegativeDependentTypeInterface<T> {
void Method(ExpensiveToCopyType E) override {}
};
template <typename T>
struct NegativeFinalImpl : public NegativeDependentTypeInterface<T> {
void Method(ExpensiveToCopyType E) final {}
};
struct PositiveConstructor {
PositiveConstructor(ExpensiveToCopyType E) : E(E) {}
// CHECK-MESSAGES: [[@LINE-1]]:43: warning: the parameter 'E' is copied
// CHECK-FIXES: PositiveConstructor(const ExpensiveToCopyType& E) : E(E) {}
ExpensiveToCopyType E;
};
struct NegativeUsingConstructor : public PositiveConstructor {
using PositiveConstructor::PositiveConstructor;
};
void fun() {
ExpensiveToCopyType E;
NegativeUsingConstructor S(E);
}
template<typename T>
void templateFunction(T) {
}
template<>
void templateFunction<ExpensiveToCopyType>(ExpensiveToCopyType E) {
// CHECK-MESSAGES: [[@LINE-1]]:64: warning: the parameter 'E' is copied
// CHECK-FIXES: void templateFunction<ExpensiveToCopyType>(ExpensiveToCopyType E) {
E.constReference();
}