test/instanceSize.m

   1 #include "test.h"
   2
   3 #include <objc/runtime.h>
   4
   5
   6 @interface Super { id isa; } @end
   7 @implementation Super
   8 +(void)initialize { }
   9 +class { return self; }
  10 +new { return class_createInstance(self, 0); }
  11 -(void)dealloc { object_dispose(self); }
  12 @end
  13
  14 @interface Sub1 : Super {
  15     // id isa;  // 0..4
  16     BOOL b;     // 4..5
  17 }
  18 @end
  19
  20 @implementation Sub1 @end
  21
  22 @interface Sub2 : Sub1 {
  23     // id isa   // 0..4    0..8
  24     // BOOL b   // 4..5    8..9
  25     BOOL b2;    // 5..6    9..10
  26     id o;       // 8..12   16..24
  27 }
  28 @end
  29 @implementation Sub2 @end
  30
  31 @interface Sub3 : Sub1 {
  32     // id isa;  // 0..4    0..8
  33     // BOOL b;  // 4..5    8..9
  34     id o;       // 8..12   16..24
  35     BOOL b2;    // 12..13  24..25
  36 }
  37 @end
  38 @implementation Sub3 @end
  39
  40 int main()
  41 {
  42     testassert(sizeof(id) == class_getInstanceSize([Super class]));
  43     testassert(2*sizeof(id) == class_getInstanceSize([Sub1 class]));
  44     testassert(3*sizeof(id) == class_getInstanceSize([Sub2 class]));
  45     testassert(4*sizeof(id) == class_getInstanceSize([Sub3 class]));
  46
  47     id o;
  48
  49     o = [Super new];
  50     testassert(object_getIndexedIvars(o) == (char *)o + class_getInstanceSize(o->isa));
  51     [o dealloc];
  52     o = [Sub1 new];
  53     testassert(object_getIndexedIvars(o) == (char *)o + class_getInstanceSize(o->isa));
  54     [o dealloc];
  55     o = [Sub2 new];
  56     testassert(object_getIndexedIvars(o) == (char *)o + class_getInstanceSize(o->isa));
  57     [o dealloc];
  58     o = [Sub3 new];
  59     testassert(object_getIndexedIvars(o) == (char *)o + class_getInstanceSize(o->isa));
  60     [o dealloc];
  61
  62     succeed(__FILE__);
  63 }