public void AddValidation_DoesNotTrounceExistingAttributes()
        {
            // Arrange
            var expectedMessage = ValidationAttributeUtil.GetRequiredErrorMessage("Length");
            var provider        = TestModelMetadataProvider.CreateDefaultProvider();
            var metadata        = provider.GetMetadataForProperty(typeof(string), "Length");

            var attribute = new RequiredAttribute();
            var adapter   = new RequiredAttributeAdapter(attribute, stringLocalizer: null);

            var actionContext = new ActionContext();
            var context       = new ClientModelValidationContext(actionContext, metadata, provider, new AttributeDictionary());

            context.Attributes.Add("data-val", "original");
            context.Attributes.Add("data-val-required", "original");

            // Act
            adapter.AddValidation(context);

            // Assert
            Assert.Collection(
                context.Attributes,
                kvp => { Assert.Equal("data-val", kvp.Key); Assert.Equal("original", kvp.Value); },
                kvp => { Assert.Equal("data-val-required", kvp.Key); Assert.Equal("original", kvp.Value); });
        }
        public void AddValidation_AddsValidation_Localize()
        {
            // Arrange
            var provider = TestModelMetadataProvider.CreateDefaultProvider();
            var metadata = provider.GetMetadataForProperty(typeof(string), "Length");

            var attribute = new RequiredAttribute();

            var expectedProperties = new object[] { "Length" };
            var message            = "This paramter is required.";
            var expectedMessage    = "FR This parameter is required.";

            attribute.ErrorMessage = message;

            var stringLocalizer = new Mock <IStringLocalizer>();

            stringLocalizer.Setup(s => s[attribute.ErrorMessage, expectedProperties])
            .Returns(new LocalizedString(attribute.ErrorMessage, expectedMessage));

            var adapter = new RequiredAttributeAdapter(attribute, stringLocalizer: stringLocalizer.Object);

            var actionContext = new ActionContext();
            var context       = new ClientModelValidationContext(actionContext, metadata, provider, new AttributeDictionary());

            // Act
            adapter.AddValidation(context);

            // Assert
            Assert.Collection(
                context.Attributes,
                kvp => { Assert.Equal("data-val", kvp.Key); Assert.Equal("true", kvp.Value); },
                kvp => { Assert.Equal("data-val-required", kvp.Key); Assert.Equal(expectedMessage, kvp.Value); });
        }