NSJSONSerialization not creating mutable containers

Question

Here\'s the code:

NSError *parseError;
NSMutableArray *listOfObjects = [NSJSONSerialization JSONObjectWithData:[@\"[]\" dataUsingEncoding:NSUTF8StringEncodin         


        

Answer 1

Here's my workaround for this problem:

#import "NSJSONSerialization+MutableBugFix.h"

@implementation NSJSONSerialization (NSJSONSerialization_MutableBugFix)

+ (id)JSONObjectWithDataFixed:(NSData *)data options:(NSJSONReadingOptions)opt error:(NSError **)error {
    id object = [NSJSONSerialization JSONObjectWithData:data options:opt error:error];

    if (opt & NSJSONReadingMutableContainers) {
        return [self JSONMutableFixObject:object];
    }

    return object;
}

+ (id)JSONMutableFixObject:(id)object {
    if ([object isKindOfClass:[NSDictionary class]]) {
        // NSJSONSerialization creates an immutable container if it's empty (boo!!)
        if ([object count] == 0) {
            object = [object mutableCopy];
        }

        for (NSString *key in [object allKeys]) {
            [object setObject:[self JSONMutableFixObject:[object objectForKey:key]] forKey:key];
        }
    } else if ([object isKindOfClass:[NSArray class]]) {
        // NSJSONSerialization creates an immutable container if it's empty (boo!!)
        if (![object count] == 0) {
            object = [object mutableCopy];
        }

        for (NSUInteger i = 0; i < [object count]; ++i) {
            [object replaceObjectAtIndex:i withObject:[self JSONMutableFixObject:[object objectAtIndex:i]]];
        }
    }

    return object;
}

@end

So I call:

NSDictionary *object = [NSJSONSerialization JSONObjectWithDataFixed:jsonData options:NSJSONReadingMutableContainers error:&err];

Instead of the usual:

NSDictionary *object = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&err];