[BUG] SKMatrix IsInvertible property crashes the debugger silently on trying to peek an variable values

[Mikolaytis]

1. Open visual studio
2. Write a simple console app that creates an SKMatrix into a variable and prints it in a second row.
3. Launch app with debugging and try to peek values of SKMatrix.
4. App is crashed.

Source of a crash is IsInvertible property.

Me and 2 other devs has this issue. I hope you can repro it too. This issue is critical, because it disables any matrix calculation debugging scenarios.

[Mikolaytis]

@mattleibow This issue is not unit-testable. Here is a screenshot of a problem:

Here is a bit detailed steps:

1. create empty project in the visual studio and write next thing:

            var matrix = SkiaSharp.SKMatrix.CreateIdentity();
            Console.WriteLine("Hello World!" + matrix);

2. set breakpoint to the second line with writeLine.
3. launch app with debugger attached
4. hover mouse over matrix property declaration and expand properties list
5. observe crash from screenshot above

[Mikolaytis]

Disabling property evaluation is not a fix of a problem, because this option is essential for debugging.

[Mikolaytis]

I think marking the IsInvertible property with [DebuggerBrowsable(DebuggerBrowsableState.Never)] should do the trick. I'll check this and will provide a PR.

[mattleibow]

@Mikolaytis sorry I didn't ping you over the weekend. But thought you would have seen my pr I merged.

That should fix it and the bits are already out on the preview feed. Unless you saw that already and it didn't fix the issue?

It should be fixed in preview 9. You can check out the actual fix mono/skia@a7b3674

Basically, the managed code was passing null as the dest matrix, but then I didn't check it.

[Mikolaytis]

@mattleibow I've missed your mono/skia commit. I've seen only unit test. Thought that you did not understand my bug and just added unit test, and closed the issue. It turns out I was wrong :)

[mattleibow]

☺

Let me know if the preview works for you! I think I am reaching the first preview of 2.80.3 very soon. A nice bunch of fixes and features.

[Mikolaytis]

preview 9 - issue fixed! thanks

[mattleibow]

Thanks for the feedback!