public async Task ProcessAsync_WithoutSpecifyingRenderMode_ThrowsError()
{
// Arrange
var tagHelper = new ComponentTagHelper
{
ViewContext = GetViewContext(),
};
var context = GetTagHelperContext();
var output = GetTagHelperOutput();
// Act & Assert
await ExceptionAssert.ThrowsArgumentAsync(
() => tagHelper.ProcessAsync(context, output),
nameof(RenderMode),
"A value for the 'render-mode' attribute must be supplied to the 'component' tag helper.");
}
public async Task ProcessAsync_WithEmptyNameFor_Throws()
{
// Arrange
var expectedTagName = "span";
var expectedMessage = "The name of an HTML field cannot be null or empty. Instead use methods " +
"Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper.Editor or Microsoft.AspNetCore.Mvc.Rendering." +
"IHtmlHelper`1.EditorFor with a non-empty htmlFieldName argument value.";
var metadataProvider = new EmptyModelMetadataProvider();
var modelExpression = CreateModelExpression(string.Empty);
var htmlGenerator = new TestableHtmlGenerator(metadataProvider);
var viewContext = TestableHtmlGenerator.GetViewContext(
model: null,
htmlGenerator: htmlGenerator,
metadataProvider: metadataProvider);
var validationMessageTagHelper = new ValidationMessageTagHelper(htmlGenerator)
{
For = modelExpression,
ViewContext = viewContext,
};
var tagHelperContext = new TagHelperContext(
expectedTagName,
new TagHelperAttributeList
{
{ "for", modelExpression },
},
new Dictionary <object, object>(),
"test");
var output = new TagHelperOutput(
expectedTagName,
new TagHelperAttributeList(),
(_, __) => Task.FromResult <TagHelperContent>(new DefaultTagHelperContent()));
// Act & Assert
await ExceptionAssert.ThrowsArgumentAsync(
() => validationMessageTagHelper.ProcessAsync(tagHelperContext, output),
paramName : "expression",
exceptionMessage : expectedMessage);
}
