Testing Basics

Assert Equal

Compare an expected value with an actual value.

testing Equality assertions make the expected result visible, then compare it with the value produced by the code under test.

Assert Equal

actual
AssertEqual.cs
Replay: real traced execution (multi-file project)
using System;

class Program
{
    static void Main()
    {
        int actual = 10;
        int expected = 10;
        bool equal = actual == expected;
        string message = equal ? "values match" : "values differ";

        Console.WriteLine($"expected={expected}");
        Console.WriteLine($"actual={actual}");
        Console.WriteLine($"equal={equal}");
        Console.WriteLine(message);
    }
}

using System;

class Program
{
    static void Main()
    {
        int actual = 9;
        int expected = 10;
        bool equal = actual == expected;
        string message = equal ? "values match" : "values differ";

        Console.WriteLine($"expected={expected}");
        Console.WriteLine($"actual={actual}");
        Console.WriteLine($"equal={equal}");
        Console.WriteLine(message);
    }
}

using System;

class Program
{
    static void Main()
    {
        int actual = 12;
        int expected = 10;
        bool equal = actual == expected;
        string message = equal ? "values match" : "values differ";

        Console.WriteLine($"expected={expected}");
        Console.WriteLine($"actual={actual}");
        Console.WriteLine($"equal={equal}");
        Console.WriteLine(message);
    }
}

  1. actual ← 10, expected ← 10, equal ← True, message ← values match

    4{5    static void Main()6    {7        int actual→ 10 = 10; //@actual=9, 128        int expected→ 10 = 10;9        bool equal→ True = actual10 == expected10;10        string message→ values match = equalTrue ? "values match" : "values differ";1112        Console.WriteLine($"expected={expected10}");13        Console.WriteLine($"actual={actual10}");14        Console.WriteLine($"equal={equalTrue}");15        Console.WriteLine(messagevalues match);16    }
    outputexpected=10
actual=10
equal=True
values match

  1. actual ← 9, expected ← 10, equal ← False, message ← values differ

    4{5    static void Main()6    {7        int actual→ 9 = 9;8        int expected→ 10 = 10;9        bool equal→ False = actual9 == expected10;10        string message→ values differ = equalFalse ? "values match" : "values differ";1112        Console.WriteLine($"expected={expected10}");13        Console.WriteLine($"actual={actual9}");14        Console.WriteLine($"equal={equalFalse}");15        Console.WriteLine(messagevalues differ);16    }
    outputexpected=10
actual=9
equal=False
values differ

  1. actual ← 12, expected ← 10, equal ← False, message ← values differ

    4{5    static void Main()6    {7        int actual→ 12 = 12;8        int expected→ 10 = 10;9        bool equal→ False = actual12 == expected10;10        string message→ values differ = equalFalse ? "values match" : "values differ";1112        Console.WriteLine($"expected={expected10}");13        Console.WriteLine($"actual={actual12}");14        Console.WriteLine($"equal={equalFalse}");15        Console.WriteLine(messagevalues differ);16    }
    outputexpected=10
actual=12
equal=False
values differ