dotnet-testing

name	dotnet-testing
description	Defines .NET test strategy and implementation patterns across xUnit v3 (Facts, Theories, fixtures, IAsyncLifetime), integration testing (WebApplicationFactory, Testcontainers), BDD (Reqnroll, lightweight xUnit Given/When/Then), Aspire testing (DistributedApplicationTestingBuilder), snapshot testing (Verify, scrubbing), Playwright E2E browser automation, BenchmarkDotNet microbenchmarks, code coverage (Coverlet), mutation testing (Stryker.NET), UI testing (page objects, selectors), and AOT WASM test compilation. Spans 14 topic areas. Do not use for production API architecture or CI workflow authoring.
license	MIT
user-invocable	false

dotnet-testing

Overview

Testing strategy, frameworks, and quality tooling for .NET applications. This consolidated skill spans 14 topic areas. Load the appropriate companion file from references/ based on the routing table below.

Baseline dependency: references/testing-strategy.md defines the unit vs integration vs E2E decision tree and test doubles selection that inform all testing decisions. Load it by default whenever a testing approach needs to be chosen.

Most-shared companion: references/xunit.md covers xUnit v3 framework features used by integration, snapshot, and UI testing companions.

Routing Table

Path resolution: The Companion File column lists filenames relative to this skill's directory. Use Glob to locate the file (pattern: ), then pass the returned absolute path to the Read tool. Do NOT use bare relative paths — the Read tool resolves them relative to the user's project directory, not this skill's location.

Topic	Keywords	Description	Companion File
Strategy	unit vs integration vs E2E, test doubles	Unit vs integration vs E2E decision tree, test doubles selection	references/testing-strategy.md
xUnit	Facts, Theories, fixtures, parallelism	xUnit v3 Facts, Theories, fixtures, parallelism, IAsyncLifetime	references/xunit.md
Integration	WebApplicationFactory, Testcontainers, Aspire	WebApplicationFactory, Testcontainers, Aspire, database fixtures	references/integration-testing.md
Snapshot	Verify, scrubbing, API responses	Verify library, scrubbing, custom converters, HTTP response snapshots	references/snapshot-testing.md
Playwright	E2E browser, CI caching, trace viewer	Playwright E2E browser automation, CI caching, trace viewer, codegen	references/playwright.md
BenchmarkDotNet	microbenchmarks, memory diagnosers	BenchmarkDotNet microbenchmarks, memory diagnosers, baselines	references/benchmarkdotnet.md
CI benchmarking	threshold alerts, baseline tracking	CI benchmark regression detection, threshold alerts, baseline tracking	references/ci-benchmarking.md
Test quality	Coverlet, Stryker.NET, flaky tests	Coverlet code coverage, Stryker.NET mutation testing, flaky tests	references/test-quality.md
Add testing	scaffold xUnit project, coverlet, layout	Scaffold xUnit project, coverlet setup, directory layout	references/add-testing.md
Slopwatch	LLM reward hacking detection	Slopwatch CLI for LLM reward hacking detection	references/slopwatch.md
AOT WASM	Blazor/Uno WASM AOT, size, lazy loading	Blazor/Uno WASM AOT compilation, size vs speed, lazy loading, Brotli	references/aot-wasm.md
UI testing core	page objects, selectors, async waits	Page object model, test selectors, async waits, accessibility testing	references/ui-testing-core.md
Aspire testing	DistributedApplicationTestingBuilder, Aspire test host	Aspire test host, service HTTP clients, resource health	references/aspire-testing.md
BDD	Given/When/Then, Reqnroll, SpecFlow alternative, scenario	Reqnroll (MIT), lightweight xUnit BDD, .feature files, scenario outlines	references/bdd.md

Scope

• Test strategy and architecture (unit, integration, E2E)
• xUnit v3 test authoring
• Integration testing (WebApplicationFactory, Testcontainers)
• BDD (Reqnroll, lightweight Given/When/Then patterns)
• E2E browser testing (Playwright)
• Snapshot testing (Verify)
• Benchmarking (BenchmarkDotNet, CI gating)
• Quality (coverage, mutation testing)
• Cross-framework UI testing patterns
• Test scaffolding

Out of scope

• UI framework-specific testing (bUnit, Appium) -> [skill:dotnet-ui]
• CI/CD pipeline configuration -> [skill:dotnet-devops]
• Performance profiling -> [skill:dotnet-tooling]