System under test
A system under test is the software, hardware, component, configuration, or other subject whose behavior is exercised and evaluated by testing.
Unit Testing Principles, Practices, and Patterns
The system under test is the class, component, or larger unit whose behavior a test exercises and verifies.
- How it is used
- Frames unit-test boundaries and clarifies which behavior or code is being verified.
- How deep it goes
- Contrasts class-centered and behavior-centered boundaries, then demonstrates each with collaborator-isolation examples.
- Examples
- Uses customer purchases, store inventory, mocks, and interaction verification to contrast classical and London-style tests.
- What you can do after
- Evaluate whether a test verifies meaningful behavior or over-specifies the SUT's implementation and collaborator interactions.
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The Art of Unit Testing 3e
A system under test is the subject, system, suite, component, class, or code being tested.
- How it is used
- Names the production behavior a unit test invokes and evaluates.
- How deep it goes
- Defines the SUT and relates it to entry points, exit points, and units of work without detailing framework internals.
- Examples
- Uses `sum('1,2')` and `verifyPassword` with a failing rule as test targets.
- What you can do after
- Evaluate/understand which production behavior a test targets and name that behavior, scenario, and expected result clearly.
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gRPC Microservices in Go
A system under test is the software element whose behavior is being evaluated, ranging from a class or layer to an entire application.
- How it is used
- Identifies the exact software element targeted by a test, from a class or layer to a service or entire application.
- How deep it goes
- Defines scope and test phases, then stops short of prescribing one testing strategy or dependency setup.
- Examples
- Uses Fibonacci testing, an Order service, MySQL dependencies, test containers, and mocked PaymentPort and DBPort interfaces.
- What you can do after
- Evaluate/understand behavior by isolating a target, controlling dependencies, and verifying expected results across test scenarios.
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Shipping Go: Develop, deliver, discuss, design, and go again
A system under test is the bounded software unit whose behavior is evaluated by a test.
- How it is used
- Structures testing around bounded units whose inputs and outputs can be evaluated independently.
- How deep it goes
- Defines black-box boundaries and identifies service, handler, and server roles, but does not descend into testing internals.
- Examples
- Uses a Go translation service, HTTP handler, server, and given-when-then translation scenario.
- What you can do after
- Build testable service, handler, and server boundaries, then evaluate behavior through inputs and expected outputs.
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Related concepts
- @SpringBootTestconfigured by · @SpringBootTest is a Spring Boot testing annotation that loads an application context with Spring Boot support for integration testing.
- evaluation suiteused by · An evaluation suite is an organized collection of tests, cases, or tasks used to assess a system against specified behaviors or criteria.
- automation solutionused by · An automation solution is a supporting system that integrates automated tests, execution frameworks, libraries, environments, and glue code to verify another system’s behavior.
- testused by · A test is a procedure or check that evaluates behavior using specified inputs or evidence against expected results or criteria.
- mockingused by · Mocking is a testing technique that replaces a real dependency with a controlled substitute to simulate behavior or inspect interactions.
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