Question

How does the Assert.AreEqual(object, object) method (in the namespace Microsoft.VisualStudio.TestTools.UnitTesting) determine whether the parameters are equal? Does it make use of the Object.Equals(object, object) method (in the System namespace)?

Answer 1

using reflector you can see that it does indeed use Object.Equals.

public static void AreEqual<T>(T expected, T actual, string message, params object[] parameters)
{
    if (!object.Equals(expected, actual))
    {
        string str;
        if (((actual != null) && (expected != null)) && !actual.GetType().Equals(expected.GetType()))
        {
            str = (string) FrameworkMessages.AreEqualDifferentTypesFailMsg((message == null) ? string.Empty : ReplaceNulls(message), ReplaceNulls(expected), expected.GetType().FullName, ReplaceNulls(actual), actual.GetType().FullName);
        }
        else
        {
            str = (string) FrameworkMessages.AreEqualFailMsg((message == null) ? string.Empty : ReplaceNulls(message), ReplaceNulls(expected), ReplaceNulls(actual));
        }
        HandleFail("Assert.AreEqual", str, parameters);
    }
}