RNFSManager iOS 14.5.1 crash

[acidumirae]

I am getting the following crash on iOS 14.5.1

Exception '*** -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[4]' was thrown while invoking readDir on target RNFSManager with params (
    "/var/mobile/Containers/Data/Application/98538D77-2F00-4B2B-A327-C08D6DC4058C",
    26,
    27
)
callstack: (
	0   CoreFoundation                      0x000000018465e5c8 58500388-BF36-397C-84CF-17315A3445B6 + 1217992
	1   libobjc.A.dylib                     0x00000001990dd7a8 objc_exception_throw + 60
	2   CoreFoundation                      0x00000001846d0a80 58500388-BF36-397C-84CF-17315A3445B6 + 1686144
	3   CoreFoundation                      0x00000001846dcad8 58500388-BF36-397C-84CF-17315A3445B6 + 1735384
	4   CoreFoundation                      0x000000018454b360 58500388-BF36-397C-84CF-17315A3445B6 + 90976
	5   CoreFoundation                      0x000000018453dc80 58500388-BF36-397C-84CF-17315A3445B6 + 35968
	6   WorkerEval                          0x0000000100c18c74 __41-[RNFSManager readDir:resolver:rejecter:]_block_invoke + 636
	7   WorkerEval                          0x0000000100c186c0 __42-[NSArray(Map) rnfs_mapObjectsUsingBlock:]_block_invoke + 112
	8   CoreFoundation                      0x00000001845dc41c 58500388-BF36-397C-84CF-17315A3445B6 + 685084
	9   CoreFoundation                      0x0000000184536d44 58500388-BF36-397C-84CF-17315A3445B6 + 7492
	10  WorkerEval                          0x0000000100c18600 -[NSArray(Map) rnfs_mapObjectsUsingBlock:] + 272
	11  WorkerEval                          0x0000000100c1891c -[RNFSManager readDir:resolver:rejecter:] + 360
	12  CoreFoundation                      0x0000000184663874 58500388-BF36-397C-84CF-17315A3445B6 + 1239156
	13  CoreFoundation                      0x0000000184536ba4 58500388-BF36-397C-84CF-17315A3445B6 + 7076
	14  CoreFoundation                      0x00000001845371a8 58500388-BF36-397C-84CF-17315A3445B6 + 8616
	15  WorkerEval                          0x0000000100d2ab14 -[RCTModuleMethod invokeWithBridge:module:arguments:] + 1752
	16  WorkerEval                          0x0000000100d2de58 _ZN8facebook5reactL11invokeInnerEP9RCTBridgeP13RCTModuleDatajRKN5folly7dynamicE + 604
	17  WorkerEval                          0x0000000100d2da38 _ZZN8facebook5react15RCTNativeModule6invokeEjON5folly7dynamicEiENK3$_0clEv + 128
	18  WorkerEval                          0x0000000100d2d9ac ___ZN8facebook5react15RCTNativeModule6invokeEjON5folly7dynamicEi_block_invoke + 28
	19  libdispatch.dylib                   0x000000010403c064 _dispatch_call_block_and_release + 32
	20  libdispatch.dylib                   0x000000010403dd90 _dispatch_client_callout + 20
	21  libdispatch.dylib                   0x0000000104045ea0 _dispatch_lane_serial_drain + 788
	22  libdispatch.dylib                   0x0000000104046cc4 _dispatch_lane_invoke + 444
	23  libdispatch.dylib                   0x0000000104053a00 _dispatch_workloop_worker_thread + 1600
	24  libsystem_pthread.dylib             0x00000001d01967a4 _pthread_wqthread + 276
	25  libsystem_pthread.dylib             0x00000001d019d74c start_wqthread + 8
)
RCTFatal
facebook::react::invokeInner(RCTBridge*, RCTModuleData*, unsigned int, folly::dynamic const&)
facebook::react::RCTNativeModule::invoke(unsigned int, folly::dynamic&&, int)::$_0::operator()() const
invocation function for block in facebook::react::RCTNativeModule::invoke(unsigned int, folly::dynamic&&, int)
_dispatch_call_block_and_release
_dispatch_client_callout
_dispatch_lane_serial_drain
_dispatch_lane_invoke
_dispatch_workloop_worker_thread
_pthread_wqthread
start_wqthread

This appears to be here:

https://github.com/itinance/react-native-fs/blob/master/RNFSManager.m#L63

It is crashing on trying to read a hidden file which the app does not have access to, even it is in apps directory:

.com.apple.mobile_container_manager.metadata.plist

A patch like this to skip the hidden files makes the crash go away:

59,69c59
<   NSMutableArray *tagetContents = [[NSMutableArray alloc] init];
<   NSArray *sourceContents = [fileManager contentsOfDirectoryAtPath:dirPath error:&error];
<   for (NSString *object in sourceContents) {
<     unichar firstChar = [object characterAtIndex:0];
<     if(firstChar == '.') {
<         NSLog(@"Skipping the hidden file: %@", object);
<     } else {
<         [tagetContents addObject:object];
<     }
<   }
<   NSArray *contents = [tagetContents copy];
---
>   NSArray *contents = [fileManager contentsOfDirectoryAtPath:dirPath error:&error];

[desmondmc]

@itinance I think you can close this issue. Looks like it's been fixed.