AppCheckCore crashes during CI runs in #45
Description
Context
GoogleSignIn-iOS uses AppCheckCore to provide Firebase AppCheck tokens during the sign in flow to provide app authenticity signal. To help developers onboard and understand how to configure their apps to use AppCheck, we provide a sample app and example unit tests to model good practices when reading sensitive AppCheck information (e.g., the web API key). Unfortunately, the tests fail when running in a CI environment (interestingly, they pass locally).
The Error
From an example workflow, the failure is: -[FBLPromise HTTPResponse]: unrecognized selector sent to instance.
2023-12-11 20:56:09.612997+0000 AppAttestExample[3626:16038] -[FBLPromise HTTPResponse]: unrecognized selector sent to instance 0x600000b2b120
2023-12-11 20:56:09.686759+0000 AppAttestExample[3626:16038] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[FBLPromise HTTPResponse]: unrecognized selector sent to instance 0x600000b2b120'
*** First throw call stack:
(
0 CoreFoundation 0x0000000112d168ab __exceptionPreprocess + 242
1 libobjc.A.dylib 0x00000001101f3ba3 objc_exception_throw + 48
2 CoreFoundation 0x0000000112d25ab8 +[NSObject(NSObject) instanceMethodSignatureForSelector:] + 0
3 CoreFoundation 0x0000000112d1ad71 ___forwarding___ + 1431
4 CoreFoundation 0x0000000112d1d068 _CF_forwarding_prep_0 + 120
5 AppAttestExample 0x000000010fab45f1 -[GACAppCheckAPIService validateHTTPResponseStatusCode:] + 81
6 AppAttestExample 0x000000010fab37a5 __78-[GACAppCheckAPIService sendRequestWithURL:HTTPMethod:body:additionalHeaders:]_block_invoke.14 + 69
7 AppAttestExample 0x000000010fad0785 __56-[FBLPromise chainOnQueue:chainedFulfill:chainedReject:]_block_invoke.67 + 85
8 AppAttestExample 0x000000010fad003a __44-[FBLPromise observeOnQueue:fulfill:reject:]_block_invoke_2 + 106
9 libdispatch.dylib 0x00000001177ce7fb _dispatch_call_block_and_release + 12
10 libdispatch.dylib 0x00000001177cfa3a _dispatch_client_callout + 8
11 libdispatch.dylib 0x00000001177df3d7 _dispatch_main_queue_drain + 1509
12 libdispatch.dylib 0x00000001177dede4 _dispatch_main_queue_callback_4CF + 31
13 CoreFoundation 0x0000000112c75b1f __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 9
14 CoreFoundation 0x0000000112c70436 __CFRunLoopRun + 2482
15 CoreFoundation 0x0000000112c6f6a7 CFRunLoopRunSpecific + 560
16 XCTestCore 0x00000001466d55b1 -[XCTWaiter waitForExpectations:timeout:enforceOrder:] + 886
17 XCTestCore 0x00000001466a48f6 -[XCTFuture _waitForFulfillment] + 716
18 XCTestCore 0x00000001466a5cce -[XCTFuture value] + 32
19 XCTestCore 0x00000001466ca01d -[XCTestDriver _prepareTestConfigurationAndIDESession] + 677
20 XCTestCore 0x00000001466c9d48 -[XCTestDriver run] + 23
21 XCTestCore 0x000000014669daa9 _XCTestMain + 125
22 libXCTestBundleInject.dylib 0x000000010fe8e9b5 __copy_helper_block_e8_32s + 0
23 CoreFoundation 0x0000000112c75dd9 __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
24 CoreFoundation 0x0000000112c75592 __CFRunLoopDoBlocks + 406
25 CoreFoundation 0x0000000112c6fe15 __CFRunLoopRun + 913
26 CoreFoundation 0x0000000112c6f6a7 CFRunLoopRunSpecific + 560
27 GraphicsServices 0x000000011a36b28a GSEventRunModal + 139
28 UIKitCore 0x000000012511fad3 -[UIApplication _run] + 994
29 UIKitCore 0x00000001251249ef UIApplicationMain + 123
30 SwiftUI 0x00000001147e7667 __swift_memcpy93_8 + 11936
31 SwiftUI 0x00000001147e7514 __swift_memcpy93_8 + 11597
32 SwiftUI 0x0000000113e4b7e9 __swift_memcpy195_8 + 12255
33 AppAttestExample 0x000000010fa71e23 $s16AppAttestExample0abcA0V5$mainyyFZ + 35
34 AppAttestExample 0x000000010fa72019 main + 9
35 dyld 0x000000010ff4e2bf start_sim + 10
36 ??? 0x0000000115d1552e 0x0 + 4661007662
)
What I Expect
No crash during CI.
Notes
Seems like AppCheckCore is somehow passing a FBLPromise to -[GACAppCheckAPIService validateHTTPResponseStatusCode:], which would lead to HTTPResponse being called on a FBLPromise and an unrecognized selector exception.