await open_file.OpenFile.open(fileLocation); crash

[hc2088]

Trapped uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[2]'
(
0 CoreFoundation 0x000000010d44d378 __exceptionPreprocess + 242
1 libobjc.A.dylib 0x000000010c411baf objc_exception_throw + 48
2 CoreFoundation 0x000000010d4d4641 -[__NSCFString characterAtIndex:].cold.1 + 0
3 CoreFoundation 0x000000010d4ded66 -[__NSPlaceholderDictionary initWithObjects:forKeys:count:].cold.5 + 0
4 CoreFoundation 0x000000010d4bfc7f -[__NSPlaceholderDictionary initWithObjects:forKeys:count:] + 243
5 CoreFoundation 0x000000010d44bfaa +[NSDictionary dictionaryWithObjects:forKeys:count:] + 49
6 QuickLookUICore 0x0000000166f1db45 __49+[QLItem(PreviewInfo) contentTypesToPreviewTypes]_block_invoke + 528
7 libdispatch.dylib 0x0000<…>
[Bugly] Fatal signal(6) raised.
[Bugly] Forward signal(6) to the previous handler: 0x0