Moq Skill

Moq provides type-safe mocking for .NET unit tests. Sorcha uses Moq extensively across 30+ test projects to isolate components and verify interactions. The codebase favors constructor injection with mocks stored as private readonly fields.

Quick Start

Basic Mock Setup

public class WalletManagerTests
{
    private readonly Mock<ICryptoModule> _mockCryptoModule;
    private readonly Mock<IHashProvider> _mockHashProvider;

    public WalletManagerTests()
    {
        _mockCryptoModule = new Mock<ICryptoModule>();
        _mockHashProvider = new Mock<IHashProvider>();
    }
}

Async Method Mock

_mockCryptoModule
    .Setup(x => x.GenerateKeySetAsync(
        It.IsAny<WalletNetworks>(),
        It.IsAny<byte[]>(),
        It.IsAny<CancellationToken>()))
    .ReturnsAsync(CryptoResult<KeySet>.Success(keySet));

Verification

_mockRegisterManager.Verify(
    m => m.CreateRegisterAsync("Test Register", "tenant-123", false, true, It.IsAny<CancellationToken>()),
    Times.Once);

Key Concepts

Concept	Usage	Example
Mock<T>	Create mock instance	new Mock<IService>()
.Object	Get mock instance	_mock.Object
Mock.Of<T>()	Quick mock for simple deps	Mock.Of<ILogger<T>>()
Setup()	Configure behavior	.Setup(x => x.Method())
ReturnsAsync()	Async return value	.ReturnsAsync(result)
Callback()	Capture arguments	.Callback<T>((arg) => captured = arg)
Verify()	Assert method called	.Verify(x => x.Method(), Times.Once)
It.IsAny<T>()	Match any argument	It.IsAny<string>()
It.Is<T>()	Match with predicate	It.Is<T>(x => x.Id == 1)

Common Patterns

Logger Mock (Quick)

When: You need a logger but don't care about verifying logs.

var service = new WalletManager(Mock.Of<ILogger<WalletManager>>());

Options Pattern Mock

When: Injecting IOptions<T> dependencies.

var mockConfig = new Mock<IOptions<PeerServiceConfiguration>>();
mockConfig.Setup(x => x.Value).Returns(new PeerServiceConfiguration { Enabled = true });

See Also

• patterns - Detailed setup and verification patterns
• workflows - Test writing workflows and integration testing

Related Skills

• See the xunit skill for test framework patterns
• See the fluent-assertions skill for assertion syntax
• See the entity-framework skill for mocking DbContext

Documentation Resources

Fetch latest Moq documentation with Context7.

How to use Context7:

1. Use mcp__context7__resolve-library-id to search for "moq"
2. Query with mcp__context7__query-docs using the resolved library ID

Library ID: /devlooped/moq

Recommended Queries:

• "moq setup verify async methods"
• "moq callbacks parameter capture"
• "moq argument matching It.Is"