Kiểm Tra Đơn Vị trong C# sử dụng xUnit Hướng Dẫn Chi Tiết

dotnet new classlib -n MyLibrary
cd MyLibrary

// Calculator.cs
namespace MyLibrary
{
    public class Calculator
    {
        public int Add(int a, int b)
        {
            return a + b;
        }
    }
}

cd ..
dotnet new xunit -n MyLibrary.Tests
cd MyLibrary.Tests
dotnet add reference ../MyLibrary/MyLibrary.csproj

// CalculatorTests.cs
using Xunit;
using MyLibrary;

namespace MyLibrary.Tests
{
    public class CalculatorTests
    {
        [Fact]
        public void Add_ShouldReturnSumOfTwoNumbers()
        {
            // Arrange
            var calculator = new Calculator();
            int a = 5;
            int b = 10;
            
            // Act
            int result = calculator.Add(a, b);
            
            // Assert
            Assert.Equal(15, result);
        }
    }
}

dotnet test

Test run for ...\MyLibrary.Tests.dll (.NETCoreApp,Version=v5.0)
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
...
Test Run Successful.
Total tests: 1
     Passed: 1
 Total time: 1.2345 Seconds

[Fact]
public void Add_ShouldReturnNegativeForNegativeInputs()
{
    // Arrange
    var calculator = new Calculator();
    int a = -5;
    int b = -10;
    
    // Act
    int result = calculator.Add(a, b);
    
    // Assert
    Assert.Equal(-15, result);
}

[Fact]
public void Add_ShouldReturnZeroWhenBothInputsAreZero()
{
    // Arrange
    var calculator = new Calculator();
    int a = 0;
    int b = 0;
    
    // Act
    int result = calculator.Add(a, b);
    
    // Assert
    Assert.Equal(0, result);
}

[Theory]
[InlineData(1, 2, 3)]
[InlineData(-1, -2, -3)]
[InlineData(0, 0, 0)]
public void Add_ShouldReturnExpectedResult(int a, int b, int expected)
{
    // Arrange
    var calculator = new Calculator();
    
    // Act
    int result = calculator.Add(a, b);
    
    // Assert
    Assert.Equal(expected, result);
}