NSObject-Safe

Update 2019.07.04

• add overflow/negative support for NSRange

1: negative value
    - NSUInteger  > NSIntegerMax
2: overflow
    - (a+ b) > a

Update 2018.11.20

• add thread-safe support

Update 2018.6.26

• remove unused swizze for NSDictionary objectForKey:
• more class cluster support

NSArray
    NSArrayI_Transfer, NSArrayReversed, NSFrozenArrayM, NSCFArray
NSString
    NSTaggedPointerString, _NSCFString, NSCFConstantString
NSData
    NSConcreteData, NSConcreteMutableData, NSZeroData, NSInlineData, __NSCFData

Warn:

• Compile NSObjectSafe.m with -fno-objc-arc, otherwise it will cause strange release error: [UIKeyboardLayoutStar release]: message sent to deallocated instance
• Conflict with MultiDelegate

Desciption

• Swizzle commonly used function of Foundation container to prevent nil crash
• Hook forwardInvocation to catch unrecognized selector exception
• Assert in Debug and log in Release

Usage:

• involve NSObjectSafe.h/NSObjectSafe.m as build phases

unrecognized selector protection

• NSSafeProxy: unrecognized selector [print:] sent to A

@interface A : NSObject
(void)print:(NSString*)msg;
@end
@implementation A
@end

Object Literals

NSArray* item = nil;
NSArray * items = @[@"a",@"b", item ,@"c"];
NSLog(@"%@", items);
NSString* key = nil; NSString* value = nil; NSLog(@"%@", @{@"b":@"c",key:value, @"e":value});

Swizzle Functions:

• NSObject(Swizzle):

+ (void)swizzleClassMethod:(SEL)origSelector withMethod:(SEL)newSelector;
(void)swizzleInstanceMethod:(SEL)origSelector withMethod:(SEL)newSelector;

- (void) addObserver:(NSObject )observer forKeyPath:(NSString )keyPath 
						options:(NSKeyValueObservingOptions)options context:(void *)context;
(void) removeObserver:(NSObject )observer forKeyPath:(NSString )keyPath;

+ (NSString) stringWithUTF8String:(const char )nullTerminatedCString;
(nullable instancetype) stringWithCString:(const char *)cString encoding:(NSStringEncoding)enc;
(nullable instancetype) initWithCString:(const char *)nullTerminatedCString encoding:(NSStringEncoding)encoding;
(NSString )stringByAppendingString:(NSString )aString;

• NSMutableString

- (nullable instancetype) safeInitWithCString:(const char *)nullTerminatedCString encoding:(NSStringEncoding)encoding;
(void) appendString:(NSString *)aString;
(void) insertString:(NSString *)aString atIndex:(NSUInteger)loc;
(void) deleteCharactersInRange:(NSRange)range;
(NSString )stringByAppendingString:(NSString )aString;

• NSArray

+ (instancetype) arrayWithObject:(id)anObject;
(id) objectAtIndex:(NSUInteger)index;

• NSMutableArray

- (void) addObject:(id)anObject;
(id) objectAtIndex:(NSUInteger)index;
(void) insertObject:(id)anObject atIndex:(NSUInteger)index;
(void) removeObjectAtIndex:(NSUInteger)index;
(void) replaceObjectAtIndex:(NSUInteger)index withObject:(id)anObject;
(void) removeObjectsInRange:(NSRange)range;

• NSDictionary

+ (instancetype) dictionaryWithObject:(id)object forKey:(id)key;
(id) objectForKey:(id)aKey;

• NSMutableDictionary

- (id) objectForKey:(id)aKey;
(void) setObject:(id)anObject forKey:(id)aKey;
(void) removeObjectForKey:(id)aKey;

+ (instancetype)setWithObject:(id)object;

• NSMutableSet

- (void) addObject:(id)object;
(void) removeObject:(id)object;

+ (instancetype)orderedSetWithObject:(id)object;
(instancetype)initWithObject:(id)object;
(id)objectAtIndex:(NSUInteger)idx;

• NSMutableOrderedSet

- (id)objectAtIndex:(NSUInteger)idx;
(void)addObject:(id)object;
(void)insertObject:(id)object atIndex:(NSUInteger)idx;
(void)removeObjectAtIndex:(NSUInteger)idx;
(void)replaceObjectAtIndex:(NSUInteger)idx withObject:(id)object;

- (id) objectForKey:(NSString *)defaultName;
(NSInteger) integerForKey:(NSString *)defaultName;
(BOOL) boolForKey:(NSString *)defaultName;
(void) setObject:(id)value forKey:(NSString*)aKey;
(void) removeObjectForKey:(NSString*)aKey;