Bug 51299 - UTType.GetDescription throws ArgumentNullException
Summary: UTType.GetDescription throws ArgumentNullException
Alias: None
Product: Xamarin.Mac
Classification: Desktop
Component: Library (Xamarin.Mac.dll) ()
Version: 2.10.0 (C8)
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-01-09 11:46 UTC by juanjo.a
Modified: 2017-01-09 19:02 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description juanjo.a 2017-01-09 11:46:59 UTC
UTType.GetDescription(string uti) in Mobilecoreservices

throws ArgumentNullException when the argument is not null, and does not throw the exception when the argument is null.

Looking at the Xamarin source code /src/MobileCoreServices/UTType.cs

public string GetDescription (string uti)
			if (uti != null)
				throw new ArgumentNullException ("uti");

			var a = NSString.CreateNative (uti);
			var ret = NSString.FromHandle (UTTypeCopyDescription (a));
			NSString.ReleaseNative (a);
			return ret;

It should be 
if (uti == null)
Comment 1 Chris Hamons 2017-01-09 14:59:37 UTC
Woops. You are correct.
Comment 2 Chris Hamons 2017-01-09 15:02:57 UTC
Comment 3 Chris Hamons 2017-01-09 19:02:25 UTC
Fixed in master and cycle9.

Thanks for the report. This will be fixed in the next major release.