bUnit - Blazor Component Testing

Overview

bUnit is a testing library for Blazor components that enables testing without a browser. It provides:

• Component rendering in a test environment
• DOM assertions and markup verification
• User interaction simulation (clicks, inputs, form submissions)
• Service mocking and dependency injection
• Async testing with waiting utilities
• Blazor lifecycle testing

Installation

# Add bUnit with xUnit support
dotnet add package bunit

# Or individual packages
dotnet add package bunit.core
dotnet add package bunit.web
dotnet add package bunit.xunit   # For xUnit integration

Quick Start

Basic Component Test

public class CounterTests : TestContext
{
    [Fact]
    public void Counter_InitialCount_IsZero()
    {
        // Arrange & Act
        var cut = RenderComponent<Counter>();

        // Assert
        cut.Find("p").MarkupMatches("<p>Current count: 0</p>");
    }

    [Fact]
    public void Counter_ClickButton_IncrementsCount()
    {
        // Arrange
        var cut = RenderComponent<Counter>();

        // Act
        cut.Find("button").Click();

        // Assert
        cut.Find("p").MarkupMatches("<p>Current count: 1</p>");
    }
}

Additional Resources

For detailed guidance, see:

• Getting Started - Project setup, global usings
• Core Concepts - TestContext, assertions, interactions
• Best Practices - Testing patterns, AAA, semantic matching
• Running Tests - CLI commands, filtering, CI integration
• Component Testing Patterns - Parameters, templates, child components
• Service Mocking - DI, KnockOff stubs, Moq patterns, HttpClient
• MudBlazor Testing - Testing MudBlazor components
• Async Testing - WaitForState, WaitForAssertion, timers
• Neatoo Testing - Testing with Neatoo domain objects

Official Documentation

• bUnit Documentation
• bUnit GitHub
• Blazor Testing Best Practices