Crash in FileUtils:resolveType when UTTypeCreatePreferredIdentifierForTag returns NULL

[blaugold]

flutter_file_picker/ios/Classes/FileUtils.m

Lines 52 to 54 in 5b9dc6e

	CFStringRef UTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (__bridge CFStringRef)[format pathExtension], NULL);
	NSString * UTIString = (__bridge NSString *)(UTI);
	CFRelease(UTI);

FileUtils:resolveType does not expect UTTypeCreatePreferredIdentifierForTag to return NULL but that is what is returned when a file extension is not a known tag class.

Using json, for example, in allowedExtensions and type: FileType.custom causes a crash on iOS Simulator.

file_picker: ^4.6.0

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[miguelpruivo]

Hum, interesting. Does this happen on a real device?

[blaugold]

Just tried it on an iPhone and the crash does not happen there.

I worded the issue a bit incorrect. UTTypeCreatePreferredIdentifierForTag returns NULL when the tag class is not known and has nothing to do with the extension that is passed in.
Is it possible that kUTTagClassFilenameExtension is not supported on iOS simulator?

[blaugold]

After googling a bit, I found basically the same issue in another project, and it seems to be Apple Silicon related.

[miguelpruivo]

I had that idea as well — that it was related with M1 issues on simulators. Unless it happens directly on real devices, this is low priority (if there is something that can actually be done or it should be fixed in a near future).

[blaugold]

I think a fix is pretty simple. Just handle the case where nil is returned as the file type not being supported. I can submit a PR if you think that sounds fine.

[miguelpruivo]

I think a fix is pretty simple. Just handle the case where nil is returned as the file type not being supported. I can submit a PR if you think that sounds fine.

Ok feel free to do it! Don't forget to also increase the patch version as well update the CHANGELOG.

Thank you!