3. Describe the Concepts of Test-Driven Development 200-901 Practice Questions (Page 5)

Questions 21–25

1. 21foundation · easy

   What does test coverage measure in a software project?

   • AThe number of tests that pass
   • BThe time it takes to run the test suite
   • CThe number of developers writing tests
   • DThe percentage of code that is executed by tests
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2. 22expert · hard

   A developer is using TDD to build a function that retrieves the CPU utilization of a network device via SNMP. The function takes a device object and returns a float. The developer writes a test that mocks the SNMP session to return a specific OID value. The test fails because the function is not implemented. After implementing the function, the test passes. The developer then notices that the function contains a hardcoded OID that should be configurable. What should the developer do?

   • AChange the function to return the OID instead of the CPU value
   • BRefactor the function to accept the OID as a parameter, then update the test to pass the OID and re-run
   • CWrite a new test for the configurable OID before refactoring
   • DLeave the hardcoded OID because the test passes
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4. 23application · easy

   A network automation engineer is adding a function to parse SNMP trap OIDs. Following TDD, they first write a test that expects parse_oid('1.3.6.1.4.1.9.9') to return ['1','3','6','1','4','1','9','9']. The test fails because the function does not exist yet. What is the next step in the TDD cycle?

   • ARefactor parse_oid to use a more efficient parsing algorithm
   • BAdd more test cases for different OID formats before implementing
   • CWrite the minimal implementation of parse_oid to make the test pass
   • DRun the full test suite to confirm the failure is not caused by other code
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5. 24foundation · easy

   What is the primary characteristic of a unit test?

   • AIt verifies a single component or function in isolation
   • BIt checks the performance of the system under load
   • CIt tests the entire application end-to-end
   • DIt validates the user interface layout
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6. 25foundation · easy

   Why is test coverage important in test-driven development?

   • AIt guarantees that all bugs are found
   • BIt helps identify untested parts of the codebase
   • CIt replaces the need for code reviews
   • DIt measures the performance of the application
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