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