public void GetHashCodeWithNullInstanceThrowsArgumentNullException()
{
// Arrange
var journalIssnEqualityComparer = new JournalIssnEqualityComparer();
Journal nullJournal = null;
// Act
// Assert
Assert.Throws <ArgumentNullException>(() => journalIssnEqualityComparer.GetHashCode(nullJournal));
}
public void EqualsWithOnlyOneInstanceIsNullReturnsFalse()
{
// Arrange
var journalIssnEqualityComparer = new JournalIssnEqualityComparer();
Journal nullJournalX = null;
Journal journalY = new Journal();
// Act
var journalsAreEqual = journalIssnEqualityComparer.Equals(nullJournalX, journalY);
// Assert
Assert.False(journalsAreEqual);
}
public void EqualsWithBothInstancesAreNullReturnsTrue()
{
// Arrange
var journalIssnEqualityComparer = new JournalIssnEqualityComparer();
Journal nullJournalX = null;
Journal nullJournalY = null;
// Act
var journalsAreEqual = journalIssnEqualityComparer.Equals(nullJournalX, nullJournalY);
// Assert
Assert.True(journalsAreEqual);
}
public void EqualsWithInstancesWithDifferentISSNsReturnsFalse()
{
// Arrange
var journalIssnEqualityComparer = new JournalIssnEqualityComparer();
var journalX = new Journal {
ISSN = "abc"
};
var journalY = new Journal {
ISSN = "123"
};
// Act
var journalsAreEqual = journalIssnEqualityComparer.Equals(journalX, journalY);
// Assert
Assert.False(journalsAreEqual);
}
public void GetHashCodeOnInstancesWithDifferentISSNReturnsDifferentHashCode()
{
// Arrange
var journalIssnEqualityComparer = new JournalIssnEqualityComparer();
var journalX = new Journal {
ISSN = "abc"
};
var journalY = new Journal {
ISSN = "123"
};
// Act
var hashCodeX = journalIssnEqualityComparer.GetHashCode(journalX);
var hashCodeY = journalIssnEqualityComparer.GetHashCode(journalY);
// Assert
Assert.NotEqual(hashCodeX, hashCodeY);
}
