Update Razor compiler to use global:: more liberally

[MichelArendt]

Issue: In a Razor Component any variables named "Microsoft" reproduce the error (variable type on the error message changes accordingly):

Error CS1061 'string' does not contain a definition for 'AspNetCore' and no accessible extension method 'AspNetCore' accepting a first argument of type 'string' could be found (are you missing a using directive or an assembly reference?)

Question: Is this an issue or by design?

Project details and files: This is a Razor Class Library project.

.csproj

<Project Sdk="Microsoft.NET.Sdk.Razor">

  <PropertyGroup>
    <TargetFramework>netstandard2.1</TargetFramework>
    <RazorLangVersion>3.0</RazorLangVersion>
    <LangVersion>8</LangVersion>
    <Nullable>enable</Nullable>
  </PropertyGroup>


  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.Components" Version="3.1.1" />
    <PackageReference Include="Microsoft.AspNetCore.Components.Web" Version="3.1.1" />
  </ItemGroup>

</Project>

LoginFormUserComponent.razor

@using SBL.Models.User.Login.OpenId

<div class="login">
    <div class="page-title">
        Login
    </div>

    <p>
        To login you must use one of the available Social Login options below:
    </p>

    <div class="social-login__container">
        <SocialButtonLoginComponent Provider="@Facebook" Image="/images/social/brands/facebook_37x37.png" />
        <SocialButtonLoginComponent Provider="@Google" Image="/images/social/brands/google_37x37.png" />
        @*<SocialButtonLoginComponent Provider="@Microsoft" Image="/images/social/brands/microsoft_37x37.png" />*@
        <SocialButtonLoginComponent Provider="@Twitter" Image="/images/social/brands/twitter_37x37.png" />
    </div>
</div>

@code {
    [Parameter]
    public ProviderOpenIdModel? Facebook { get; set; } = null;

    [Parameter]
    public ProviderOpenIdModel? Google { get; set; } = null;

    //[Parameter]
    //public ProviderOpenIdModel? Microsoft { get; set; } = null; // ERROR

    [Parameter]
    public ProviderOpenIdModel? Twitter { get; set; } = null;

    public string Microsoft { get; set; } // ERROR
}

Comments:
I started getting this random error and found out that apparently I cannot write "Microsoft" as a variable name in a Razor component.

I was unable to find the search keywords for anything similar to this.

I initially thought that there was a reference issue on my project when I realized the commented parameter was the issue. I then tried using a native variable type to see if the issue persisted - and it did.

It's not really an issue I need fixing per say - just wondering why this happens.

Thanks in advance!

[pranavkm]

Thanks for the issue report @MichelArendt. This looks like a bug in Razor's code generation. Unfortunately there isn't a very good workaround for this outside of using a different member name.

A fix for this would be to globally qualify the Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.TypeCheck call.

protected override void BuildRenderTree(Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder) 
        {
            __builder.AddMarkupContent(0, "<h1>Hello, world!</h1>\r\n\r\nWelcome to your new app.\r\n\r\n");
            __builder.OpenComponent<b.Pages.Counter>(1);
            __builder.AddAttribute(2, "Model", Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.TypeCheck<b.MyModel>( // here
                Microsoft
            ));
            __builder.CloseComponent();
        }

    public MyModel Microsoft { get; set; } // ERROR

[Rick-Anderson]

@pranavkm I can make a doc issue of this and add Microsoft to Razor reserved keywords. Let me know if you'd like to go that route.

[pranavkm]

@Rick-Anderson this is not a reserved keyword though. Presumably once we fix the underlying issue, this should work.