/// <summary>
/// Asserts that the <see cref="IComposableLut.LookupValues"/> method produces the same results as performing individual lookups via <see cref="IComposableLut.this"/>.
/// </summary>
/// <param name="lut">The <see cref="IComposableLut"/> implementation under test.</param>
/// <param name="minTestInputValue">Specifies the input test value range.</param>
/// <param name="maxTestInputValue">Specifies the input test value range.</param>
/// <param name="message">Message for NUnit Assertions.</param>
/// <param name="args">Args for <paramref name="message"/>.</param>
public static void AssertLookupValues(this IComposableLut lut, int minTestInputValue, int maxTestInputValue, string message = null, params object[] args)
{
const int countGuards = 9;
const double baseGuard = 12.3456789;
Platform.CheckTrue(minTestInputValue <= maxTestInputValue, "max test input value must be greater than or equal to min test input value");
var count = maxTestInputValue - minTestInputValue + 1;
var actualValues = new double[count + countGuards];
var msg = !string.IsNullOrEmpty(message) ? " - " + string.Format(message, args) : null;
// populate the array with test input values
for (var i = 0; i < count; ++i)
{
actualValues[i] = minTestInputValue + i;
}
// populate end of array with guard values
for (var i = 0; i < countGuards; ++i)
{
actualValues[count + i] = baseGuard * i;
}
// perform lookup (function under test)
lut.LookupValues(actualValues, actualValues, count);
// assert the result values
for (var i = 0; i < count; ++i)
{
Assert.AreEqual(lut[minTestInputValue + i], actualValues[i], "LookupValues output @{0} (Value {1}){2}", i, minTestInputValue + i, msg);
}
// assert the guard values
for (var i = 0; i < countGuards; ++i)
{
Assert.AreEqual(baseGuard * i, actualValues[count + i], "LookupValues overruns allotted buffer @{0}{1}", count + i, msg);
}
}
