Validation source code generation not working for annotated field

[nickrandolph]

Describe the bug

If you annotate a field with ObservableProperty along with validation attributes, the generated source code for the ValidateAllProperties method doesn't include all the properties.

Steps to Reproduce

Create a class that inherits from ObservableValidator and has at least one field that has the ObservableProperty and validation attributes, eg:

public partial class MainViewModel : ObservableValidator
{
    [Required()]
    [MinLength(2,
        ErrorMessageResourceType = typeof(ErrorResolver),
        ErrorMessageResourceName = nameof(ErrorResolver.CustomMinLength))]
    [MaxLength(100)]
    [Display(Name = "FirstName", ResourceType = typeof(DisplayResolver))]
    [ObservableProperty]
    private string first = "Bob";

    [Display(Name = nameof(DisplayResolver.LastName), ResourceType = typeof(DisplayResolver))]
    [Required(
        ErrorMessageResourceType = typeof(ErrorResolver),
        ErrorMessageResourceName = nameof(ErrorResolver.CustomRequired))]
    [MinLength(2,
        ErrorMessageResourceType = typeof(ErrorResourceResolver),
        ErrorMessageResourceName = nameof(ErrorResourceResolver.MinLengthError))]
    [MaxLength(100)]
    [NoSpecialCharacters]
    [CustomValidation(typeof(MainViewModel), nameof(StartsWithUppercaseValidation))]
    [ObservableProperty]
    private string last = "Jones";

    public static ValidationResult StartsWithUppercaseValidation(object value, ValidationContext context)
    {
        var text = value + "";
        var isValid = string.IsNullOrWhiteSpace(text) ? false : char.IsUpper(text.First());
        return isValid ? ValidationResult.Success : new ValidationResult(null);
    }
}

Compile code and look at the generated code in the __ObservableValidatorExtensions class.
Generated code looks like:

internal static partial class __ObservableValidatorExtensions
{
    [global::System.ComponentModel.EditorBrowsable(global::System.ComponentModel.EditorBrowsableState.Never)]
    [global::System.Obsolete("This method is not intended to be called directly by user code")]
    public static global::System.Action<object> CreateAllPropertiesValidator(global::WinUIControl.MainViewModel _)
    {
        static void ValidateAllProperties(object obj)
        {
            var instance = (global::WinUIControl.MainViewModel)obj;
        }

        return ValidateAllProperties;
    }
}

Expected behavior

Generated code should look similar to:

internal static partial class __ObservableValidatorExtensions
{
    [global::System.ComponentModel.EditorBrowsable(global::System.ComponentModel.EditorBrowsableState.Never)]
    [global::System.Obsolete("This method is not intended to be called directly by user code")]
    public static global::System.Action<object> CreateAllPropertiesValidator(global::WinUIControl.MainViewModel _)
    {
        static void ValidateAllProperties(object obj)
        {
            var instance = (global::WinUIControl.MainViewModel)obj;
            __ObservableValidatorHelper.ValidateProperty(instance, instance.First, nameof(instance.First));
            __ObservableValidatorHelper.ValidateProperty(instance, instance.Last, nameof(instance.Last));
        }

        return ValidateAllProperties;
    }
}

Screenshots

N/A

Environment

N/A

NuGet Package(s):
Microsoft.Toolkit.Mvvm v7.1.0-preview1

Package Version(s):

Windows 10 Build Number:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• Insider Build ({build_number})
• Windows 11

App min and target version:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• [ X ] October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• Insider Build ({build_number})

Device form factor:

• Desktop
• Xbox
• Surface Hub
• IoT

Visual Studio version:

• 2017 (15.{minor_version})
• 2019 (16.{minor_version})
• 2022 (17.{minor_version})

Additional context

N/A

Hello nickrandolph, thank you for opening an issue with us!

I have automatically added a "needs triage" label to help get things started. Our team will analyze and investigate the issue, and escalate it to the relevant team if possible. Other community members may also look into the issue and provide feedback 🙌

[michael-hawker]

FYI @Sergio0694

[Sergio0694]

Thanks for the report @nickrandolph!
This is caused by the fact that source generators are not run in a specified order (by design) and each only sees the initial input. So the one generating that validation method won't see the generated properties with the generated attributes copied over from the fields, hence that body will not contain the expected validation. I'll need to add a dedicated code path to also inspect declared fields marked with [ObservableProperty] and with at least one validation attribute, just like with properties 🙂

[nickrandolph]

Let me know when the change is available and I'll grab a build and test it out.