reference, declaration → definition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced

    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103

// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare "-Dnil=((id)0)" -verify %s
// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare "-Dnil=(id)0" -verify %s
// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare "-Dnil=0" -verify %s

// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare -fobjc-arc "-Dnil=((id)0)" -verify %s
// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare -fobjc-arc "-Dnil=(id)0" -verify %s
// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare -fobjc-arc "-Dnil=0" -verify %s

// (test the warning flag as well)

typedef signed char BOOL;

@interface BaseObject
+ (instancetype)new;
@end

@interface NSObject : BaseObject
- (BOOL)isEqual:(id)other;
@end

@interface NSNumber : NSObject
+ (NSNumber *)numberWithInt:(int)value;
+ (NSNumber *)numberWithDouble:(double)value;
+ (NSNumber *)numberWithBool:(BOOL)value;
@end

@interface NSArray : NSObject
+ (id)arrayWithObjects:(const id [])objects count:(unsigned long)cnt;
@end

@interface NSDictionary : NSObject
+ (id)dictionaryWithObjects:(const id [])objects forKeys:(const id [])keys count:(unsigned long)cnt;
@end

@interface NSString : NSObject
@end

void testComparisonsWithFixits(id obj) {
  if (obj == @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (obj != @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@"" == obj) return; // expected-warning{{direct comparison of a string literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@"" == @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}

  if (@[] == obj) return; // expected-warning{{direct comparison of an array literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@{} == obj) return; // expected-warning{{direct comparison of a dictionary literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@12 == obj) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@1.0 == obj) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@__objc_yes == obj) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@(1+1) == obj) return; // expected-warning{{direct comparison of a boxed expression has undefined behavior}} expected-note{{use 'isEqual:' instead}}
}


@interface BadEqualReturnString : NSString
- (void)isEqual:(id)other;
@end

@interface BadEqualArgString : NSString
- (BOOL)isEqual:(int)other;
@end


void testComparisonsWithoutFixits() {
  if ([BaseObject new] == @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}

  if ([BadEqualReturnString new] == @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
  if ([BadEqualArgString new] == @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}

  if (@"" < @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
  if (@"" > @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
  if (@"" <= @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
  if (@"" >= @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
}


#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wobjc-string-compare"

void testWarningFlags(id obj) {
  if (obj == @"") return; // no-warning
  if (@"" == obj) return; // no-warning

  if (obj == @1) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
  if (@1 == obj) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
}

#pragma clang diagnostic pop


void testNilComparison() {
  // Don't warn when comparing to nil in a macro.
#define RETURN_IF_NIL(x) if (x == nil || nil == x) return
  RETURN_IF_NIL(@"");
  RETURN_IF_NIL(@1);
  RETURN_IF_NIL(@1.0);
  RETURN_IF_NIL(@[]);
  RETURN_IF_NIL(@{});
  RETURN_IF_NIL(@__objc_yes);
  RETURN_IF_NIL(@(1+1));
}

void PR15257(Class c) {
  return c == @""; // expected-warning{{direct comparison of a string literal has undefined behavior}}
}