有人能帮我理解一下这种罕见且随机的崩溃吗？有没有办法修复此问题而不会重现？线程 0 名称：线程 0 崩溃：0 libdispatch.dylib
有人能帮我理解一下这种罕见且随机的崩溃吗？有没有办法修复这个问题而不让它重现？
Thread 0 name:
Thread 0 Crashed:
0 libdispatch.dylib 0x00000001b2d7e538 _dispatch_sync_f + 4 (queue.c:1898)
1 Security 0x00000001b372d0d8 SecTrustGetCertificateAtIndex + 244 (SecTrust.c:0)
2 PK9 0x0000000102d63124 __61+[CertificateUtils certificatesFromTrust:options:completion:]_block_invoke + 88 (CertificateUtils.m:201)
3 CoreFoundation 0x00000001aadb51b8 __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 28 (CFRunLoop.c:1805)
4 CoreFoundation 0x00000001aadb39ac __CFRunLoopDoBlocks + 356 (CFRunLoop.c:1847)
5 CoreFoundation 0x00000001aadb1888 __CFRunLoopRun + 812 (CFRunLoop.c:2953)
6 CoreFoundation 0x00000001aadb1478 CFRunLoopRunSpecific + 608 (CFRunLoop.c:3420)
7 GraphicsServices 0x00000001ee30a4f8 GSEventRunModal + 164 (GSEvent.c:2196)
8 UIKitCore 0x00000001ad1db360 -[UIApplication _run] + 888 (UIApplication.m:3685)
9 UIKitCore 0x00000001ad1da99c UIApplicationMain + 340 (UIApplication.m:5270)
10 PK9 0x0000000102e5dfe8 main + 68 (main.m:15)
11 dyld 0x00000001cdae9dcc start + 2240 (dyldMain.cpp:1269)
发生崩溃的函数：
+ (void)certificatesFromTrust:(SecTrustRef)trust options:(CertificateOptions)options completion:(void (^)(NSArray *))completion
{
if (trust == NULL) {
completion(nil);
}
else {
// trust needs to be evaluated prior to attempting to retrieve the certs
CFIndex count = SecTrustGetCertificateCount(trust);
[self evaluateTrust:trust completion:^(OSStatus status, SecTrustResultType result) {
NSMutableArray *certs = [NSMutableArray arrayWithCapacity:(NSInteger)count];
for (CFIndex i = 0; i < count; i++) {
SecCertificateRef cert = SecTrustGetCertificateAtIndex(trust, i);
if (cert != NULL) {
// Extract certificate data
NSData *certData = CFBridgingRelease(SecCertificateCopyData(cert));
if (certData != nil && (options & CertificateOptionsRemoveRootCertificates) && count > 1) {
// We were told to strip all anchor certificates, so only keep this one if it's issued by someone else (and not the only cert, i.e. self-signed)
const unsigned char *certDataBytes = (const unsigned char *)[certData bytes];
X509 *x509Cert = d2i_X509(NULL, &certDataBytes, [certData length]);
NSString *subjectCN = X509CertificateGetCommonName(X509_get_subject_name(x509Cert));
NSString *issuerCN = X509CertificateGetCommonName(X509_get_issuer_name(x509Cert));
X509_free(x509Cert);
if ([subjectCN isEqualToString:issuerCN]) {
certData = nil; // do not add root certificates
}
}
if (certData != nil) {
// create a copy of the certificate and add it to the array transferring ownership to ARC
cert = SecCertificateCreateWithData(NULL, (__bridge CFDataRef)(certData));
[certs addObject:CFBridgingRelease(cert)];
}
}
}
completion(certs);
}];
}
}
经过一番挖掘，我发现 XCTest 在 -only-testing MyTarget/MyClass/myTest 传递时调用测试的方式不同。更具体地说， 当在中指定单个测试时，不会调用 XCTestCase.defaultTestSuite -only-testing .
继承自（ -only-testing 当然 NSObject.instancesRespondToSelector:aSelector: 发送消息 XCTestCase 来检查它是否可以运行传入的测试 NSObject 。这似乎是一个很好的 defaultTestSuite 手动调用的钩子点，它反过来会调用 testInvocations ，它会生成测试方法并将其混入到 ParametrizedTests 类中。
我的 LandmarksTests 课程缺少该选择器的覆盖。在我将其添加到我的 ParametrizedTests 课程后：
+ (BOOL)instancesRespondToSelector:(SEL)aSelector {
[self defaultTestSuite]; // calls testInvocations
BOOL result = [super instancesRespondToSelector:aSelector];
return true;
}
它开始正常工作了！
这是最终文件，可以复制粘贴到 ParametrizedTests.m 内的 LandmarksUITests ，并且可以正常工作！
@import XCTest;
@import ObjectiveC.runtime;
@interface ParametrizedTests : XCTestCase
@end
@implementation ParametrizedTests
+ (BOOL)instancesRespondToSelector:(SEL)aSelector {
[self defaultTestSuite]; // calls testInvocations
BOOL result = [super instancesRespondToSelector:aSelector];
return true;
}
+ (NSArray<NSInvocation *> *)testInvocations {
NSLog(@"testInvocations() called");
/* Prepare dummy input */
__block NSMutableArray<NSString *> *dartTestFiles = [[NSMutableArray alloc] init];
[dartTestFiles addObject:@"example_test"];
[dartTestFiles addObject:@"permissions_location_test"];
[dartTestFiles addObject:@"permissions_many_test"];
NSMutableArray<NSInvocation *> *invocations = [[NSMutableArray alloc] init];
NSLog(@"Before the loop, %lu elements in the array", (unsigned long)dartTestFiles.count);
for (int i = 0; i < dartTestFiles.count; i++) {
/* Step 1 */
NSString *name = dartTestFiles[i];
void (^anonymousFunc)(ParametrizedTests *) = ^(ParametrizedTests *instance) {
NSLog(@"anonymousFunc called!");
};
IMP implementation = imp_implementationWithBlock(anonymousFunc);
NSString *selectorStr = [NSString stringWithFormat:@"%@", name];
SEL selector = NSSelectorFromString(selectorStr);
class_addMethod(self, selector, implementation, "v@:");
/* Step 2 */
NSMethodSignature *signature = [self instanceMethodSignatureForSelector:selector];
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
invocation.selector = selector;
NSLog(@"RunnerUITests.testInvocations(): selectorStr = %@", selectorStr);
[invocations addObject:invocation];
}
NSLog(@"After the loop");
return invocations;
}
@end
也可以看看：