TypeInfo.ConvertedType.NullableAnnotation is None when binding a 'var' keyword

[jasonmalinowski]

This is being observed in #40030 as I'm removing the IDE's nullable wrappers. If you run this test in the branch it fails. The test is calling GetTypeInfo on the argument and grabbing the ConvertedType here. The old nullability APIs say that it is indeed nullable, but the new ITypeSymbol.NullableAnnotation still says None.

I believe the expectation now is the ITypeSymbol.NullableAnnotation should have brought along the annotated state of Annotated.

[AlekseyTs]

@jasonmalinowski Could you please clearly describe the issue in following terms?

• Here is a source
• On this node/token an API is called (which API)
• Here is the result
• Here is what expected.

[jasonmalinowski]

If you look at this test, the highlighted span is the code. The [||] is the marker where we invoke the refactoring if you wanted to actually try that, otherwise delete the marker. If we call GetTypeInfo on the "var" keyword, the TypeInfo has ConvertedNullability property saying it's annotated as "string?", but the ITypeSymbol given by the ConvertedType property has a NullableAnnotation of "none". The expectation in this case would be it carries along the nullability.

If I recall, if you set a breakpoint at this line in my pull request, and run the test, the breakpoint will hit easily and you can inspect the result in that case.

[AlekseyTs]

I believe this issue should be fixed by #40338.