Editing NUnit (section)

=== Classical ===
Before NUnit 2.4, a separate method of the <code>Assert</code> class was used for each different assertion. It continues to be supported in NUnit, since many people prefer it.{{citation needed|date=January 2017}}

Each assert method may be called without a message, with a simple text message or with a message and arguments. In the last case the message is formatted using the provided text and arguments.{{citation needed|date=January 2017}}

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// Equality asserts
Assert.AreEqual(object expected, object actual);
Assert.AreEqual(object expected, object actual, string message, params object[] parms);

Assert.AreNotEqual(object expected, object actual);
Assert.AreNotEqual(object expected, object actual, string message, params object[] parms);

// Identity asserts
Assert.AreSame(object expected, object actual);
Assert.AreSame(object expected, object actual, string message, params object[] parms);

Assert.AreNotSame(object expected, object actual);
Assert.AreNotSame(object expected, object actual, string message, params object[] parms);

// Condition asserts
// (For simplicity, methods with message signatures are omitted.)
Assert.IsTrue(bool condition);
Assert.IsFalse(bool condition);

Assert.IsNull(object anObject);
Assert.IsNotNull(object anObject);

Assert.IsNaN(double aDouble);

Assert.IsEmpty(string aString);
Assert.IsNotEmpty(string aString);

Assert.IsEmpty(ICollection collection);
Assert.IsNotEmpty(ICollection collection);
</syntaxhighlight>