[.NET10-preview7] XAML Source Generator - Grid Error + Warnings

[bcaceiro]

Description

Using .net10 Preview 7 , and enabling XAML Source Generator, there is an error with Grids

<Grid RowDefinitions="25,*,1.25"/>

Results in the following build error:
'GridLength' does not contain a constructor that takes 3 arguments

There is also a warning: 'SimpleValueTargetProvider.SimpleValueTargetProvider(object[], object, INameScope[], bool)' is obsolete: 'Use the other ctor'

I have here a minimal sample, but when running in a Real project, this produces a gazillion warnings.

Steps to Reproduce

1. Create new .net MAUI App - .net 10 preview 7
2. Enable Xaml Source Generators
3. Declare a simple Grid with multiple rows / Columns
4. Build error + warnings

Link to public reproduction project repository

https://github.com/bcaceiro/net9-repros/tree/main/Maui10Preview7

Version with bug

10.0.0-preview.7

Is this a regression from previous behavior?

Yes, this used to work in .NET MAUI

Last version that worked well

10.0.0-preview.6

Affected platforms

iOS, Android, Windows, macOS

Affected platform versions

No response

Did you find any workaround?

Disable the XAML Source Generator

Relevant log output

[bcaceiro]

@jfversluis - I can not select the right version - the version with errors is preview7

This issue has been verified in Visual Studio 17.14.12 Preview 1.0 on Windows and Visual Studio Code 1.103.0 on Mac with MAUI versions 10.0.0.Preview 7. However, the mentioned warnings are reproduced, but the error does not happen. I have attached the output for reference.

Note: The XAML SourceGenerator was introduced in net10.0 preview 7 onwards.

[jfversluis]

@anandhan-rajagopal it was noted indeed that they couldn't select preview 7. And I think "it was working on preview 6" is in mistake. So this is not a regression. Thanks for checking!

However @bcaceiro same as Anandhan, I can't reproduce. I only see the warnings, not the error. How are you building exactly? For a specific platform? Are you using Windows/macOS? Visual Studio, VS Code?

[bcaceiro]

@jfversluis @anandhan-rajagopal here is the complete information :

Microsoft Visual Studio Community 2022 (64-bit) - Preview
Version 17.14.11 Preview 1.0

Build Log:

1>------ Build started: Project: Maui10Preview7, Configuration: Debug Any CPU ------
Restored C:\P\net9-repros\Maui10Preview7\Maui10Preview7.csproj (in 227 ms).
1>C:\Program Files\dotnet\sdk\10.0.100-preview.7.25380.108\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.RuntimeIdentifierInference.targets(345,5): message NETSDK1057: You are using a preview version of .NET. See: https://aka.ms/dotnet-support-policy
1>Skipping analyzers to speed up the build. You can execute 'Build' or 'Rebuild' command to run analyzers.
1>Including assemblies for Hot Reload support
1>C:\P\net9-repros\Maui10Preview7\obj\Debug\net10.0-android\Microsoft.Maui.Controls.SourceGen\Microsoft.Maui.Controls.SourceGen.CodeBehindGenerator\AppShell.xaml.xsg.cs(48,29,56,10): warning CS0618: 'SimpleValueTargetProvider.SimpleValueTargetProvider(object[], object, INameScope[], bool)' is obsolete: 'Use the other ctor'
1>C:\P\net9-repros\Maui10Preview7\obj\Debug\net10.0-android\Microsoft.Maui.Controls.SourceGen\Microsoft.Maui.Controls.SourceGen.CodeBehindGenerator\MainPage.xaml.xsg.cs(107,29,115,10): warning CS0618: 'SimpleValueTargetProvider.SimpleValueTargetProvider(object[], object, INameScope[], bool)' is obsolete: 'Use the other ctor'
1>C:\P\net9-repros\Maui10Preview7\obj\Debug\net10.0-android\Microsoft.Maui.Controls.SourceGen\Microsoft.Maui.Controls.SourceGen.CodeBehindGenerator\MainPage.xaml.xsg.cs(133,30,141,10): warning CS0618: 'SimpleValueTargetProvider.SimpleValueTargetProvider(object[], object, INameScope[], bool)' is obsolete: 'Use the other ctor'
1>C:\P\net9-repros\Maui10Preview7\obj\Debug\net10.0-android\Microsoft.Maui.Controls.SourceGen\Microsoft.Maui.Controls.SourceGen.CodeBehindGenerator\MainPage.xaml.xsg.cs(162,328,162,361): error CS1729: 'GridLength' does not contain a constructor that takes 3 arguments
1>Done building project "Maui10Preview7.csproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Error:

workloads:

Workload version: 10.0.100-preview.7.25411.1

Installed Workload Id      Manifest Version                                 Installation Source
--------------------------------------------------------------------------------------------------------------------------------------
android                    36.0.0-preview.7.229/10.0.100-preview.7          SDK 10.0.100-preview.7, VS 17.14.36408.4, VS 17.14.36401.2
ios                        18.5.10601-net10-p7/10.0.100-preview.7           SDK 10.0.100-preview.7, VS 17.14.36408.4, VS 17.14.36401.2
maccatalyst                18.5.10601-net10-p7/10.0.100-preview.7           SDK 10.0.100-preview.7, VS 17.14.36408.4, VS 17.14.36401.2
maui-windows               10.0.0-preview.7.25406.3/10.0.100-preview.7      SDK 10.0.100-preview.7, VS 17.14.36408.4, VS 17.14.36401.2

I have cleaned the solution multiple times, always the same error