我正在开发一个应用程序，列出一项运动的当前现场比赛。有关实时游戏的信息是使用 REST 从远程源获取的。第一个请求给出了一个实时游戏列表及其 ID 和相应的竞技场 ID。然后我必须从他们的 ID 中获取竞技场名称。当一切都完成后，我发回一个包含实时游戏列表的 NSArray。

在测试通过 block 传递 NSArray 的解析方法时，我在 SenTestCase 中发现了一个奇怪的行为。在我的测试中，我能够执行 [myArray count] 并将其结果显示在 NSLog 中，但是当我执行 STAsertEquals([myArray count], 1, @"Error description ")带有 EXC_BAD_ACCESS 的测试崩溃。

这里是我的代码，已减至最少并删除了所有网络方面的内容:

#import <SenTestingKit/SenTestingKit.h>


@interface LiveGameTests : SenTestCase
@end

@interface LiveGame : NSObject
@property (nonatomic) id gameID;
@property (strong, nonatomic) NSString *arenaName;
@end

@implementation LiveGame

// Create a live game object from a dictionary (this dictionary is the response of a first request to a remote server)
+(LiveGame *)gameWithData:(NSDictionary *)dict
{
    LiveGame *liveGame = [[LiveGame alloc] init];
    liveGame.gameID = dict[@"game_id"];    
    return liveGame;
}

// Complete a live game data with the element of a dictionary (those data are actualy fetched from a remote server in a different request.)
+(void)fetchRemainingData:(NSArray *)liveGameList completion:(void(^)(void))completion
{
    LiveGame *liveGame = liveGameList[0];
    liveGame.arenaName = @"arenaName";
    completion();
}

// Parse a NSArray of NSDictionaries representing live game
+(void)parseArrayOfDictionary:(NSArray *)arrayToParse success:(void(^)(NSArray *liveGameList))success
{
    NSMutableArray *liveGameList = [NSMutableArray arrayWithCapacity:[arrayToParse count]];

    // Iterate on all the NSDictionary of the NSArray and create live game from each NSDictionary 
    [arrayToParse enumerateObjectsUsingBlock:^(NSDictionary *obj, NSUInteger idx, BOOL *stop)
     {
         liveGameList[idx] = [LiveGame gameWithData:obj];
     }];

    [LiveGame fetchRemainingData:liveGameList completion:^
     {
         success(liveGameList);
     }];
}
@end

@implementation LiveGameTests

-(void)testParseArrayOfDictionary
{
    [LiveGame parseArrayOfDictionary: @[@{@"game_id": @1}]
        success:^(NSArray *liveGameList)
        {
            // This line work fine and print: 2013-03-08 13:39:35.288 ShotClock[55177:c07] liveGameList count = 1
            NSLog(@"liveGameList count = %d",[liveGameList count]);

            // This crash the test on a EXC_BAD_ACCESS. What's wrong?
            STAssertEquals([liveGameList count], 1, @"The list of game must contain one unique live game but contain %@",[liveGameList count]);
        }];
}
@end

NSLog(@"liveGameList 计数 = %d",[liveGameList 计数]); => 此行工作正常并打印:2013-03-08 13:39:35.288 ShotClock[55177:c07] liveGameList count = 1

STAsertEquals([liveGameList count], 1, @"游戏列表必须包含一个唯一的现场游戏但包含 %@",[liveGameList count]); => 这会使 EXC_BAD_ACCESS 上的测试崩溃。怎么了？

最佳答案

您的应用程序崩溃是因为

  STAssertEquals([liveGameList count], 1,  @"The list of game must contain one unique live game but contain %@",[liveGameList count])

尝试将 %@ 格式化程序应用于 [liveGameList count] 的结果。但是 %@ 需要一个 Objective C 对象，其中 [liveGameList count] 返回标量“1”。运行时将该标量转换为指向 0x00000001 的指针，并尝试使用它在那里找到的“对象”。但这不是有效指针，因此运行时会引发无效地址异常。

关于ios - Objective-C NSArray、 block 、STAsertEquals，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15294556/