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/*
* Copyright (c) 2017 - present Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
bool star();
class T {
public:
int x;
T* field;
public:
int* _Nullable mayReturnNullPointer() {
if (star()) {
return nullptr;
} else {
return new int;
}
}
public:
T* _Nullable mayReturnNullObject() {
if (star()) {
return nullptr;
} else {
return this;
}
}
public:
void doSomething() {}
};
void assignNullableValueBad(T* t) {
int* p = t->mayReturnNullPointer();
*p = 42;
}
void FP_reAssigningNullableValueOk(T* t) {
int* p = t->mayReturnNullPointer();
p = new int;
*p = 42;
}
void callMethodOnNullableObjectBad(T* t) {
t->mayReturnNullObject()->doSomething();
}
void callMethodOnNullableObjectOk(T* t) {
T* p = t->mayReturnNullObject();
if (p != nullptr) {
p->doSomething();
}
}
void dereferenceFieldOfNullableObjectBad(T* t) {
T* p = t->mayReturnNullObject();
p->x = 42;
}
void methodCallOnFieldOfNullableObjectBad(T* t) {
T* p = t->mayReturnNullObject();
p->field->doSomething();
}
void avoidDoubleReportingBad(T* t) {
T* p = t->mayReturnNullObject();
p->doSomething(); // should report here
p->doSomething(); // should not report here
}