public void PreprocessBook_ThrowsArgumentNullException_WhenBookIsNull()
{
// Act
void action() => Question16_2.PreprocessBook(null);
// Assert
TestHelpers.AssertExceptionThrown(action, typeof(ArgumentNullException));
}
public void WordFrequencyPreprocessed_ReturnsFrequency_WithOneWord()
{
// Arrange
var book = new[] { "foo" };
Question16_2.PreprocessBook(book);
// Act
var result = Question16_2.WordFrequencyPreprocessed("foo");
// Assert
Assert.AreEqual(1, result);
}
public void WordFrequencyPreprocessed_ThrowsArgumentNullException_WhenTargetWordIsNull()
{
// Arrange
var book = new[] { "foo" };
Question16_2.PreprocessBook(book);
// Act
void action() => Question16_2.WordFrequencyPreprocessed(null);
// Assert
TestHelpers.AssertExceptionThrown(action, typeof(ArgumentNullException));
}
public void WordFrequencyPreprocessed_ReturnsZero_WithNoOccurrences()
{
// Arrange
var book = new[] { "foo" };
Question16_2.PreprocessBook(book);
// Act
var result = Question16_2.WordFrequencyPreprocessed("bar");
// Assert
Assert.AreEqual(0, result);
}
