public void PlainTextCallVisitor_VisitMethod()
{
var visitorMock = new Mock <Visitor>();
var plainText = new PlainText {
Text = "Some plain text"
};
plainText.Visit(visitorMock.Object);
visitorMock.Verify(visitor => visitor.VisitPlainText(It.Is <PlainText>(text => string.Equals(text.Text, plainText.Text, StringComparison.Ordinal))), Times.Once);
}