Version: 5.6
public static void IsFalse (bool condition);
public static void IsFalse (bool condition, string message);

説明

false となる条件のアサート

public class AssertionExampleClass : MonoBehaviour
{
    GameObject go;
    void Update()
    {
        //Make sure the Game Object is never in active state
        Assert.IsFalse(go.activeSelf);
    }
}