aspnetcore/test/Microsoft.AspNet.Mvc.ModelBinding.Test/Validation/RequiredAttributeAdapterTest.cs

using System.ComponentModel.DataAnnotations;
using Microsoft.AspNet.Testing;
using Xunit;

namespace Microsoft.AspNet.Mvc.ModelBinding
{
    public class RequiredAttributeAdapterTest
    {
        [Fact]
        [ReplaceCulture]
        public void GetClientValidationRules_ReturnsValidationParameters()
        {
            // Arrange
            var provider = new DataAnnotationsModelMetadataProvider();
            var metadata = provider.GetMetadataForProperty(() => null, typeof(string), "Length");
            var attribute = new RequiredAttribute();
            var adapter = new RequiredAttributeAdapter(attribute);
            var context = new ClientModelValidationContext(metadata, provider);

            // Act
            var rules = adapter.GetClientValidationRules(context);

            // Assert
            var rule = Assert.Single(rules);
            Assert.Equal("required", rule.ValidationType);
            Assert.Empty(rule.ValidationParameters);
            Assert.Equal("The Length field is required.", rule.ErrorMessage);
        }
    }
}