How to debug Retain Count and Autorelease Count on Objective-C

gistfile1.m

+ (NSString*) stringEncodedPercentWithString:(NSString*)source
{
    NSString *encodedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)source,  NULL, (CFStringRef)@"!*'();:@&=+$,/?%#[]", kCFStringEncodingUTF8);
    [encodedString autorelease];

    // Show target's memory address.
    NSLog(@"encodedString address = 0x%p", encodedString);

    // Show target's autorelease count
    [NSAutoReleasePool showPools];

    // Show target's retain count
    NSLog(@"encodedString retainCount = %ld", [encodedString retainCount]);

    // break here
    assert(false);

    return encodedString;
}