SaaSCore.Testing 0.2.0-preview.5

SaaSCore.Testing

SaaSCore.Testing provides a lightweight set of helpers, fixtures, and utilities to support writing fast, reliable, and repeatable tests across the SaaSCore ecosystem.
It is designed to remove boilerplate when testing database interactions, specifications, and application-level components --- while remaining completely optional and unobtrusive.

This package is used internally by SaaSCore and SaaSCore.* modules but can also be referenced by consuming applications.

✨ Features

• In-memory EF Core test context
  Provides a preconfigured, lightweight TestDbContext for validating repository queries, specifications, and other EF Core logic.

• Automatic test database bootstrapping
  Creates and seeds a fresh database instance per test (or per test class), ensuring test isolation.

• Specification testing helpers
  Fluent helpers for asserting that your specifications generate the correct LINQ expressions and return the expected results.

• Extension points for custom seeding
  Easily inject your own seed data for more complex scenarios.

• EF Core options factory
  A central way to create consistent DbContextOptions<T> across tests without rewriting setup code.

📦 Installation

This package is internal for now. Once extracted into its own NuGet package, it will be installed via:

dotnet add package SaaSCore.Testing

Until then, reference the project from your solution:

<ItemGroup>
  <ProjectReference Include="..\SaaSCore.Testing\SaaSCore.Testing.csproj" />
</ItemGroup>

🚀 Getting Started

1. Use the built-in TestDbContextFactory

var options = TestDbContextFactory.CreateOptions();
await using var context = new TestDbContext(options);

2. Seed your test data (optional)

context.Seed(users: true, tenants: true);

3. Write your assertions

var results = await context.Users.ToListAsync();
Assert.NotEmpty(results);

🧪 Using Specification Helpers

Example of testing one of your UserSpecifications:

// Arrange
var spec = UserSpecifications.ByExternalId("abc-123");

// Act
var result = await context.ApplySpecification(spec).FirstOrDefaultAsync();

// Assert
Assert.NotNull(result);
Assert.Equal("abc-123", result.ExternalId);

The helpers ensure your specification is applied consistently with the real system.

🧰 Included Utilities

Utility Description

TestDbContext A dedicated EF Core DbContext tailored for tests.

TestDbContextFactory Creates in-memory EF Core options and context instances.

SeedExtensions Opinionated helpers for injecting stable test data.

SpecificationTestExtensions Shortcuts for applying and evaluating specifications.

📐 Design Principles

SaaSCore.Testing follows the core SaaSCore philosophy:

• No mocking what you can prove --- prefer real EF Core behaviour over mocked abstractions.
• Realistic data, minimal ceremony --- seed helpers give structure without forcing test complexity.
• Composable, not prescriptive --- all utilities can be replaced or extended.

🗺 Roadmap

• SQLite-backed test database for higher fidelity integration tests.
• Snapshot testing helpers.
• Additional specification assertion utilities.