1. Treat Tests as production code

   • Write tests with the same care and quality as production code.
   • Ensure tests are maintainable, readable, and well-organized.

2. Make Tests Easy to Understand

   • Use clear and consistent naming conventions to describe the purpose and behavior being tested.
   • Follow the AAA (Arrange, Act, Assert) pattern to structure tests logically:
     • Arrange: Set up the context and prerequisites.
     • Act: Perform the action being tested.
     • Assert: Verify the expected outcomes.

3. Adopt the GWT (Given, When, Then) Naming Pattern

   • Use test names that describe the scenario without explicitly including "Given", "When", or "Then".
   • Example: Instead of GivenUserLogsIn_WhenPasswordIsCorrect_ThenAccessIsGranted, use UserLogsIn_WithCorrectPassword_AccessGranted.

    [Test]
    public async Task ConfiguredXXisTrue_CallTestApiEnpointPerson_ReturnYYinResponse()
    {
        // Arrange
        var appsettingsConfig = new Dictionary<string, string?>
        {
            "XX", "true" },
            
        };
        var testConfiguration = appsettingsConfig.BuildInMemoryConfiguration();
        // Use testframework application factory to override configurations and services
        var appFactory = new TestWebApplicationFactory(testConfiguration, services =>
        {
            ..   
        });

        // Act
        var client = appFactory.CreateClient();
        var response = await client.GetAsync("api/person");

        // Assert
         var content = await response.Content.Content.ReadAsStringAsync();
         Assert.That(content, Is.EqualTo("YY"));

    }

In .NET, the following are commonly used builders for configuring and testing applications:

• HostBuilder
• WebApplicationBuilder (introduced in .NET 6 with the minimal API model)
• IWebHostBuilder (used by WebApplicationFactory) These builders can be used in integration tests to simulate different configurations, mock services, or test various application setups. It allows to test different configurations and to simulate different usages by mocking out parts of the services.

The Testframework has some helperclass for WebApplicationBuilder and IWebHostBuilder. See comparisation table below for spesification and when to use what.

Sample can be found in repository xxx