VS Code extension reports errors for valid usage of BindingExtension with x:DataType in MAUI XAML

[simonrozsival]

Type: Bug

For the following XAML code, VS Code extension will report an error message XLS0413. The XAML is correct and this error message should not be displayed. The MAUI app builds correctly, XamlC doesn’t report any errors:

<Button Text="{Binding Text, x:DataType=Label}" />

The error message:

The property 'DataType' was not found in type 'BindingExtension'.(XLS0413)

Similarly, the extension reports an unsubstantiated warning for the following (unusual) XAML:

<Button>
  <Button.Text>
    <BindingExtension Path="Text" x:DataType="Label" />
  </Button.Text>
</Button>

The warning message:

The attribute 'DataType' from the XAML namespace is not defined. (XLS1102)

Contrary to expectations, the following XAML, which isn’t correctly understood by the MAUI XamlC compiler, doesn’t produce any warnings:

<Button>
  <Button.Text x:DataType="Label">
    <BindingExtension Path="Text" />
  </Button.Text>
</Button>

Extension version: 0.11.94
VS Code version: Code 1.89.1 (dc96b837cf6bb4af9cd736aa3af08cf8279f7685, 2024-05-07T05:14:32.757Z)
OS version: Darwin arm64 23.4.0
Modes:

System Info

Item	Value
CPUs	Apple M1 Max (10 x 24)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled
Load (avg)	4, 7, 7
Memory (System)	32.00GB (0.30GB free)
Process Argv	/Users/simonrozsival/Projects/dogfooding/MyDailyPriorities --crash-reporter-id d2e2bec8-5081-4be8-b73a-9e3b61ff94de
Screen Reader	no
VM	0%

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[mgoertz-msft]

<Button Text="{Binding Text, x:DataType=Label}" />

Verified that this is fixed in the latest C# extension v2.34.12

[simonrozsival]

I confirm the issue is resolved. Thank you very much!