public void ParagraphTextSetter_ThrowsException_WhenParagraphWasRemoved() { IPresentation presentation = SCPresentation.Open(Properties.Resources._020, true); IAutoShape autoShape = (IAutoShape)presentation.Slides[2].Shapes.First(sp => sp.Id == 8); ITextBox textBox = autoShape.TextBox; IParagraph paragraph = textBox.Paragraphs.First(); textBox.Text = "new box content"; // Act-Assert paragraph.Invoking(p => p.Text = "new paragraph text") .Should().Throw <ElementIsRemovedException>("because paragraph was being removed while changing box content."); }