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| // RUN: %clang_cc1 -fsyntax-only -verify -fblocks -Wno-objc-root-class %s
// test for block type safety.
@interface Super @end
@interface Sub : Super @end
void f2(void(^f)(Super *)) { // expected-note{{passing argument to parameter 'f' here}}
Super *o;
f(o);
}
void f3(void(^f)(Sub *)) {
Sub *o;
f(o);
}
void r0(Super* (^f)()) {
Super *o = f();
}
void r1(Sub* (^f)()) { // expected-note{{passing argument to parameter 'f' here}}
Sub *o = f();
}
@protocol NSObject;
@class NSObject;
void r2 (id<NSObject> (^f) (void)) {
id o = f();
}
void test1() {
f2(^(Sub *o) { }); // expected-error {{incompatible block pointer types passing}}
f3(^(Super *o) { }); // OK, block taking Super* may be called with a Sub*
r0(^Super* () { return 0; }); // OK
r0(^Sub* () { return 0; }); // OK, variable of type Super* gets return value of type Sub*
r0(^id () { return 0; });
r1(^Super* () { return 0; }); // expected-error {{incompatible block pointer types passing}}
r1(^Sub* () { return 0; }); // OK
r1(^id () { return 0; });
r2(^id<NSObject>() { return 0; });
}
@interface A @end
@interface B @end
void f0(void (^f)(A* x)) {
A* a;
f(a);
}
void f1(void (^f)(id x)) {
B *b;
f(b);
}
void test2(void)
{
f0(^(id a) { }); // OK
f1(^(A* a) { });
f1(^(id<NSObject> a) { }); // OK
}
@interface NSArray
// Calls block() with every object in the array
-enumerateObjectsWithBlock:(void (^)(id obj))block;
@end
@interface MyThing
-(void) printThing;
@end
@implementation MyThing
static NSArray* myThings; // array of MyThing*
-(void) printThing { }
// programmer wants to write this:
-printMyThings1 {
[myThings enumerateObjectsWithBlock: ^(MyThing *obj) {
[obj printThing];
}];
}
// strict type safety requires this:
-printMyThings {
[myThings enumerateObjectsWithBlock: ^(id obj) {
MyThing *obj2 = (MyThing *)obj;
[obj2 printThing];
}];
}
@end
@protocol P, P2;
void f4(void (^f)(id<P> x)) { // expected-note{{passing argument to parameter 'f' here}}
NSArray<P2> *b;
f(b); // expected-warning {{passing 'NSArray<P2> *' to parameter of incompatible type 'id<P>'}}
}
void test3() {
f4(^(NSArray<P2>* a) { }); // expected-error {{incompatible block pointer types passing 'void (^)(NSArray<P2> *)' to parameter of type 'void (^)(id<P>)'}}
}
// rdar : //8302845
@protocol Foo @end
@interface Baz @end
@interface Baz(FooConformance) <Foo>
@end
@implementation Baz @end
int test4 () {
id <Foo> (^b)() = ^{ // Doesn't work
return (Baz *)0;
};
return 0;
}
// rdar:// 9118343
@protocol NSCopying @end
@interface NSAllArray <NSCopying>
@end
@interface NSAllArray (FooConformance) <Foo>
@end
int test5() {
// Returned value is used outside of a block, so error on changing
// a return type to a more general than expected.
NSAllArray *(^block)(id);
id <Foo> (^genericBlock)(id);
genericBlock = block;
block = genericBlock; // expected-error {{incompatible block pointer types assigning to 'NSAllArray *(^)(id)' from 'id<Foo> (^)(id)'}}
// A parameter is used inside a block, so error on changing a parameter type
// to a more specific than an argument type it will be called with.
// rdar://problem/52788423
void (^blockWithParam)(NSAllArray *);
void (^genericBlockWithParam)(id<Foo>);
genericBlockWithParam = blockWithParam; // expected-error {{incompatible block pointer types assigning to 'void (^)(id<Foo>)' from 'void (^)(NSAllArray *)'}}
blockWithParam = genericBlockWithParam;
return 0;
}
// rdar://10798770
typedef int NSInteger;
typedef enum : NSInteger {NSOrderedAscending = -1L, NSOrderedSame, NSOrderedDescending} NSComparisonResult;
typedef NSComparisonResult (^NSComparator)(id obj1, id obj2);
@interface radar10798770
- (void)sortUsingComparator:(NSComparator)c;
@end
void f() {
radar10798770 *f;
[f sortUsingComparator:^(id a, id b) {
return NSOrderedSame;
}];
}
// rdar://16739120
@protocol P1 @end
@protocol P2 @end
void Test() {
void (^aBlock)();
id anId = aBlock; // OK
id<P1,P2> anQualId = aBlock; // expected-error {{initializing 'id<P1,P2>' with an expression of incompatible type 'void (^)()'}}
NSArray* anArray = aBlock; // expected-error {{initializing 'NSArray *' with an expression of incompatible type 'void (^)()'}}
aBlock = anId; // OK
id<P1,P2> anQualId1;
aBlock = anQualId1; // expected-error {{assigning to 'void (^)()' from incompatible type 'id<P1,P2>'}}
NSArray* anArray1;
aBlock = anArray1; // expected-error {{assigning to 'void (^)()' from incompatible type 'NSArray *'}}
}
void Test2() {
void (^aBlock)();
id<NSObject> anQualId1 = aBlock; // Ok
id<NSObject, NSCopying> anQualId2 = aBlock; // Ok
id<NSObject, NSCopying, NSObject, NSCopying> anQualId3 = aBlock; // Ok
id <P1> anQualId4 = aBlock; // expected-error {{initializing 'id<P1>' with an expression of incompatible type 'void (^)()'}}
id<NSObject, P1, NSCopying> anQualId5 = aBlock; // expected-error {{initializing 'id<NSObject,P1,NSCopying>' with an expression of incompatible type 'void (^)()'}}
id<NSCopying> anQualId6 = aBlock; // Ok
}
void Test3() {
void (^aBlock)();
NSObject *NSO = aBlock; // Ok
NSObject<NSObject> *NSO1 = aBlock; // Ok
NSObject<NSObject, NSCopying> *NSO2 = aBlock; // Ok
NSObject<NSObject, NSCopying, NSObject, NSCopying> *NSO3 = aBlock; // Ok
NSObject <P1> *NSO4 = aBlock; // expected-error {{initializing 'NSObject<P1> *' with an expression of incompatible type 'void (^)()'}}
NSObject<NSObject, P1, NSCopying> *NSO5 = aBlock; // expected-error {{initializing 'NSObject<NSObject,P1,NSCopying> *' with an expression of incompatible type 'void (^)()'}}
NSObject<NSCopying> *NSO6 = aBlock; // Ok
}
// rdar://problem/19420731
typedef NSObject<P1> NSObject_P1;
typedef NSObject_P1<P2> NSObject_P1_P2;
void Test4(void (^handler)(NSObject_P1_P2 *p)) {
Test4(^(NSObject<P2> *p) { });
}
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