public void CanUseExternalExtensionDirectly()
{
IMarkdownExtension mockExtension = Substitute.For <IMarkdownExtension>();
Markdown markdown = new Markdown().UseExtension(mockExtension);
// When
// ReSharper disable once ReturnValueOfPureMethodIsNotUsed
markdown.Execute(new[] { new TestDocument(string.Empty) }, new TestExecutionContext()).ToList(); // Make sure to materialize the result list
// Then
// Setup will always be called during markdown pipeline setup.
mockExtension.Received().Setup(Arg.Any <MarkdownPipelineBuilder>());
}
