public void GetHashCode_TwoIdenticalObjects_BothUninitialized_HashCodesAreEqual()
{
// Arrange
var package1 = new SystemInformation();
var package2 = new SystemInformation();
// Act
int hashCodeObject1 = package1.GetHashCode();
int hashCodeObject2 = package2.GetHashCode();
// Assert
Assert.AreEqual(hashCodeObject1, hashCodeObject2);
}
public void GetHashCode_TwoIdenticalObjects_BothInitialized_HashCodesAreEqual()
{
// Arrange
var timestamp = DateTime.UtcNow;
var object1 = new SystemInformation
{
MachineName = Environment.MachineName,
Timestamp = timestamp,
SystemPerformance = new SystemPerformanceData()
};
var object2 = new SystemInformation
{
MachineName = Environment.MachineName,
Timestamp = timestamp,
SystemPerformance = new SystemPerformanceData()
};
// Act
int hashCodeObject1 = object1.GetHashCode();
int hashCodeObject2 = object2.GetHashCode();
// Assert
Assert.AreEqual(hashCodeObject1, hashCodeObject2);
}
public void GetHashCode_SameHashCodeIsReturnedEveryTimeTheMethodIsCalled_AsLongAsTheObjectDoesNotChange()
{
// Arrange
var machineName = Environment.MachineName;
var timeStamp = DateTime.UtcNow;
var object1 = new SystemInformation
{
MachineName = machineName,
Timestamp = timeStamp,
SystemPerformance = new SystemPerformanceData()
};
int expectedHashcode = object1.GetHashCode();
for (var i = 0; i < 100; i++)
{
// Act
object1.MachineName = machineName;
object1.Timestamp = timeStamp;
int generatedHashCode = object1.GetHashCode();
// Assert
Assert.AreEqual(expectedHashcode, generatedHashCode);
}
}
public void GetHashCode_TwoDistinctObjects_HashCodesAreDifferent()
{
// Arrange
var object1 = new SystemInformation
{
MachineName = Environment.MachineName,
Timestamp = DateTime.UtcNow,
SystemPerformance = new SystemPerformanceData()
};
var object2 = new SystemInformation
{
MachineName = "Different Machine",
Timestamp = DateTime.UtcNow,
SystemPerformance = new SystemPerformanceData()
};
// Act
int hashCodeObject1 = object1.GetHashCode();
int hashCodeObject2 = object2.GetHashCode();
// Assert
Assert.AreNotEqual(hashCodeObject1, hashCodeObject2);
}
public void GetHashCode_ForAllUniqueObject_AUniqueHashCodeIsReturned()
{
var timeStamp = DateTime.UtcNow;
var hashCodes = new Dictionary<int, SystemInformation>();
for (var i = 0; i < 1000; i++)
{
// Act
var object1 = new SystemInformation
{
MachineName = Environment.MachineName + i,
Timestamp = timeStamp,
SystemPerformance = new SystemPerformanceData()
};
int generatedHashCode = object1.GetHashCode();
// Assert
Assert.IsFalse(hashCodes.ContainsKey(generatedHashCode));
hashCodes.Add(generatedHashCode, object1);
}
}