CTFL 5.1.6: Recall the concepts of the test pyramid

• a
  Test granularity rises, test isolation rises, and execution time fallsThis reverses all three: granularity and isolation fall, and execution time rises.
• ✓
  Correct answer: Test granularity falls, test isolation falls, and execution time risesLower granularity, lower isolation, higher execution time.
• c
  Test granularity stays constant while only the degree of automation changesThe model is precisely about granularity differing between the layers.
• d
  Test granularity falls, test isolation rises, and execution time fallsIsolation falls rather than rises, and execution time rises rather than falls.

The higher the layer, the lower the test granularity, the lower the test isolation — that is, the degree of dependency on other elements of the system — and the higher the test execution time. Tests in the bottom layer are small, isolated and fast, so many are needed; the top layer holds complex end-to-end tests, of which few are needed.

Syllabus section 5.1.6

• a
  They are slow, end-to-end tests, and only a few are neededSlow end-to-end tests of which few are needed describe the top layer, not the bottom.
• b
  They are manual exploratory sessions guided by a charterThe test pyramid is about test granularity and automation, not exploratory charters.
• ✓
  Correct answer: They are small, isolated, fast, and usually many are neededBottom-layer tests are small, isolated, fast, and usually many are needed.
• d
  They check the largest pieces of end-to-end functionalityChecking the largest end-to-end pieces describes the top layer of the pyramid.

In the test pyramid, tests in the bottom layer are small, isolated, fast, and check a small piece of functionality, so many of them are usually needed. The top layer holds complex, high-level, end-to-end tests that are slower, so only a few are needed.

Syllabus section 5.1.6

• a
  Deciding which test cases to execute first within a test execution scheduleOrdering execution is test case prioritization, a different topic.
• b
  Determining the entry criteria and exit criteria for each test levelEntry and exit criteria are defined per test level, independently of this model.
• c
  Grouping test levels with the test types that are appropriate to themGrouping test levels with appropriate test types is the testing quadrants model.
• ✓
  Correct answer: Test automation and the allocation of test effort across levels of granularityTest automation and the allocation of test effort across granularity levels.

The test pyramid model supports the team in test automation and in test effort allocation by showing that different test objectives are supported by different levels of test automation. Grouping test levels with appropriate test types is what the testing quadrants model does; prioritizing execution order and defining entry and exit criteria are separate topics.

Syllabus section 5.1.6