Match the descriptions to these test doubles terms: Dummy, Stub, Spy, Mock.

Test doublesConcept relationships

Choose a match for every item. Use each answer once.

A dummy satisfies a dependency shape without supplying meaningful test behavior.

Spies capture observations such as arguments and invocation counts.

Mocks focus on verifying the required communication with a dependency.

Stubs control collaborator outputs so a test can reach a chosen scenario.