修改NSObjects的内部属性(特别是SKPaymentTransaction)

时间:2014-07-14 09:18:58

标签: ios objective-c xcode unit-testing skpaymenttransaction

我正在尝试对我们的收据验证服务器进行单元测试,虽然我可以更改内部API以避免此问题,但这意味着我们没有完全测试客户端API,所以我想避免这种情况。

作为我们API的一部分,我们通过SKPaymentTransaction,然后将Transaction.transactionReceipt传递到我们的服务器。

为了正确测试,我想创建一个SKPaymentTransaction实例,其中包含我选择的transactionReceipt(有效值和无效值)。

不幸的是,SKPaymentTransaction将transactionReceipt属性定义为只读,并且我无法声明由于this而将其定义为readwrite的扩展/子类。

我似乎也无法将SKPaymentTransaction指针强制转换为char *以手动将值注入内存中,因为Xcode不会在ARC下允许这样做。

有没有人知道我如何才能达到我想要的目标?

由于 利

2 个答案:

答案 0 :(得分:3)

原来我可以调用transactionReceipt getter将自己的数据注入到调用中。

所以我最终得到像

这样的东西
-(void)test_function
{
    SKPaymentTransaction* invalidTransaction = [[SKPaymentTransaction alloc] init];

    Method swizzledMethod = class_getInstanceMethod([self class], @selector(replaced_getTransactionReceipt));
    Method originalMethod = class_getInstanceMethod([invalidTransaction class], @selector(transactionReceipt));

    method_exchangeImplementations(originalMethod, swizzledMethod);

    // Call to receipt verification server
}

- (NSData*)replaced_getTransactionReceipt
{
    return [@"blah" dataUsingEncoding:NSUTF8StringEncoding];
}

我写了一篇博文,展示了我的流程,并在此提供了更多详细信息 http://engineering-game-dev.com/2014/07/23/injecting-data-into-obj-c-readonly-properties/

答案 1 :(得分:0)

我将SKPaymentTransaction(例如MutableSKPaymentTransaction)子类化,覆盖readonly参数。已经存在可以使用的可变SKPaymentTransaction,或者您可以以类似的方式覆盖SKPayment。

示例:

在头文件(MutableSKPaymentTransaction.h)文件中

#import <StoreKit/StoreKit.h>

@interface MutableSKPaymentTransaction : SKPaymentTransaction

@property (readwrite, copy, nonatomic) NSError * error;
@property (readwrite, copy, nonatomic) SKPayment * payment;
@property (readwrite, copy, nonatomic) NSString * transactionIdentifier;
@property (readwrite, copy, nonatomic) NSDate * transactionDate;
@property (readwrite, copy, nonatomic) NSArray * downloads;
@property (readwrite, copy, nonatomic) SKPaymentTransaction *originalTransaction;
@property (assign, nonatomic) SKPaymentTransactionState transactionState;

@end

并在方法文件(MutableSKPaymentTransaction.m)中:

#import "MutableSKPaymentTransaction.h"

@implementation MutableSKPaymentTransaction

// readonly override
@synthesize error = _error;
@synthesize payment = _payment;
@synthesize transactionIdentifier = _transactionIdentifier;
@synthesize transactionDate = _transactionDate;
@synthesize downloads = _downloads;
@synthesize originalTransaction = _originalTransaction;
@synthesize transactionState = _transactionState;

@end