اختبار العقود وتنقيحها

using System;

(int Input, int Expected)[] cases = { (-1, 0), (0, 0), (100, 100), (101, 100) };
foreach (var item in cases)
{
    if (Clamp(item.Input) != item.Expected) throw new InvalidOperationException("clamp mismatch");
}
Console.WriteLine("4 checks passed");

static int Clamp(int value) => value < 0 ? 0 : value > 100 ? 100 : value;

4 checks passed

كل نتيجة معروفة صراحة ولا يطبع النجاح إلا بعد الفحوص الأربعة.

using System;
using System.IO;
using System.Text;

using var writer = new FailingWriter();
try
{
    writer.Write("sample");
    throw new InvalidOperationException("expected write failure");
}
catch (IOException)
{
    Console.WriteLine("expected failure observed");
}

internal sealed class FailingWriter : TextWriter
{
    public override Encoding Encoding => Encoding.UTF8;
    public override void Write(string? value) => throw new IOException("synthetic write failure");
}

expected failure observed

تُلاحظ IOException الاصطناعية دون إتلاف نظام ملفات.