dotnet-testing-strategy
dotnet-testing-strategy
Decision framework for choosing the right test type, organizing test projects, and selecting test doubles in .NET applications. Covers unit vs integration vs E2E trade-offs with concrete criteria, naming conventions, and when to use mocks vs fakes vs stubs.
Out of scope: Test project scaffolding (directory layout, xUnit project creation, coverlet setup, editorconfig overrides) is owned by [skill:dotnet-add-testing]. Code coverage tooling and mutation testing are covered by [skill:dotnet-test-quality]. CI test reporting and pipeline integration -- see [skill:dotnet-gha-build-test] and [skill:dotnet-ado-build-test].
Prerequisites: Run [skill:dotnet-project-analysis] to understand the solution structure before designing a test strategy.
Cross-references: [skill:dotnet-xunit] for xUnit v3 testing framework features, [skill:dotnet-integration-testing] for WebApplicationFactory and Testcontainers patterns, [skill:dotnet-snapshot-testing] for Verify-based approval testing, [skill:dotnet-test-quality] for coverage and mutation testing, [skill:dotnet-add-testing] for test project scaffolding.
Test Type Decision Tree
Use this decision tree to determine which test type fits a given scenario. Start at the top and follow the first matching criterion.
Does the code under test depend on external infrastructure?
(database, HTTP service, file system, message broker)
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