test/addMethod.m

   1 #include "test.h"
   2 #include <objc/runtime.h>
   3
   4 @interface Super { @public id isa; } @end
   5 @implementation Super
   6 +(void)initialize { }
   7 +class { return self; }
   8 +(id) new { return class_createInstance(self, 0); }
   9
  10 -(int)superMethod { return 0; }
  11 -(int)bothMethod { return 0; }
  12 @end
  13
  14 @interface Sub : Super @end
  15 @implementation Sub
  16 -(int)subMethod { return 0; }
  17 -(int)bothMethod { return 0; }
  18 @end
  19
  20 @interface Sub2 : Super @end
  21 @implementation Sub2
  22 -(int)subMethod { return 0; }
  23 -(int)bothMethod { return 0; }
  24 @end
  25
  26
  27 id fn(id self __attribute__((unused)), SEL cmd __attribute__((unused)), ...) { return nil; }
  28
  29 int main()
  30 {
  31     IMP superMethodFromSuper = class_getMethodImplementation([Super class], @selector(superMethod));
  32     IMP bothMethodFromSuper = class_getMethodImplementation([Super class], @selector(bothMethod));
  33     IMP subMethodFromSub = class_getMethodImplementation([Sub class], @selector(subMethod));
  34     IMP bothMethodFromSub = class_getMethodImplementation([Sub class], @selector(bothMethod));
  35     IMP subMethodFromSub2 = class_getMethodImplementation([Sub2 class], @selector(subMethod));
  36     IMP bothMethodFromSub2 = class_getMethodImplementation([Sub2 class], @selector(bothMethod));
  37
  38     testassert(superMethodFromSuper);
  39     testassert(bothMethodFromSuper);
  40     testassert(subMethodFromSub);
  41     testassert(bothMethodFromSub);
  42     testassert(subMethodFromSub2);
  43     testassert(bothMethodFromSub2);
  44
  45     BOOL ok;
  46     IMP imp;
  47
  48     // class_addMethod doesn't replace existing implementations
  49     ok = class_addMethod([Super class], @selector(superMethod), &fn, NULL);
  50     testassert(!ok);
  51     testassert(class_getMethodImplementation([Super class], @selector(superMethod)) == superMethodFromSuper);
  52
  53     // class_addMethod does override superclass implementations
  54     ok = class_addMethod([Sub class], @selector(superMethod), &fn, NULL);
  55     testassert(ok);
  56     testassert(class_getMethodImplementation([Sub class], @selector(superMethod)) == &fn);
  57
  58     // class_addMethod does add root implementations
  59     ok = class_addMethod([Super class], @selector(superMethodNew2), &fn, NULL);
  60     testassert(ok);
  61     testassert(class_getMethodImplementation([Super class], @selector(superMethodNew2)) == &fn);
  62     testassert(class_getMethodImplementation([Sub class], @selector(superMethodNew2)) == &fn);
  63
  64
  65     // class_replaceMethod does add new implementations,
  66     // returning NULL if super has an implementation
  67     imp = class_replaceMethod([Sub2 class], @selector(superMethod), &fn, NULL);
  68     testassert(imp == NULL);
  69     testassert(class_getMethodImplementation([Sub2 class], @selector(superMethod)) == fn);
  70
  71     // class_replaceMethod does add new implementations,
  72     // returning NULL if super has no implementation
  73     imp = class_replaceMethod([Sub2 class], @selector(subMethodNew), &fn, NULL);
  74     testassert(imp == NULL);
  75     testassert(class_getMethodImplementation([Sub2 class], @selector(subMethodNew)) == fn);
  76
  77     // class_replaceMethod does add new implemetations
  78     // returning NULL if there is no super class
  79     imp = class_replaceMethod([Super class], @selector(superMethodNew), &fn, NULL);
  80     testassert(imp == NULL);
  81     testassert(class_getMethodImplementation([Super class], @selector(superMethodNew)) == fn);
  82
  83
  84     // class_replaceMethod does replace existing implementations,
  85     // returning existing implementation (regardless of super)
  86     imp = class_replaceMethod([Sub2 class], @selector(subMethod), &fn, NULL);
  87     testassert(imp == subMethodFromSub2);
  88     testassert(class_getMethodImplementation([Sub2 class], @selector(subMethod)) == fn);
  89
  90     // class_replaceMethod does replace existing implemetations,
  91     // returning existing implementation (regardless of super)
  92     imp = class_replaceMethod([Sub2 class], @selector(bothMethod), &fn, NULL);
  93     testassert(imp == bothMethodFromSub2);
  94     testassert(class_getMethodImplementation([Sub2 class], @selector(bothMethod)) == fn);
  95
  96     // class_replaceMethod does replace existing implemetations,
  97     // returning existing implementation (regardless of super)
  98     imp = class_replaceMethod([Super class], @selector(superMethod), &fn, NULL);
  99     testassert(imp == superMethodFromSuper);
 100     testassert(class_getMethodImplementation([Super class], @selector(superMethod)) == fn);
 101
 102     // fixme actually try calling them
 103
 104     succeed(__FILE__);
 105 }