ISTQB Updated ISTQB-CTFL Exam Questions and Answers by chiara

Test-Driven Development (TDD) emphasizes writing tests before code and includes refactoring as a key practice to improve both the tests and the code. This ensures that the codebase remains clean and maintainable. The ISTQB CTFL Syllabus v4.0 discusses TDD as a practice that includes writing tests first, coding to satisfy those tests, and then refactoring the code to improve its structure and readability while keeping the tests intact​​.

An oracle is a mechanism or source that can provide the expected result for a given test input or situation. Sometimes old version of a product can be used as an oracle, if it is assumed that the old version behaves correctly for the test cases that are executed on the new version. This is also known as back-to-back testing. Oracles do not help in reproducing the irreproducible bugs, as they only provide the expected results, not the actual results. Oracles are not derived from the design, but from the requirements or specifications. Oracles cannot be generated automatically using data generators, as data generators only provide test inputs, not test outputs. Verified References: A Study Guide to the ISTQB® Foundation Level 2018 Syllabus - Springer, page 9.

The minimum number of test cases needed to cover every unique sequence of up to 3 states/2 transitions starting in the “Start” state and ending in the “End” state is 4. This is because there are 4 unique sequences of up to 3 states/2 transitions starting in the “Start” state and ending in the “End” state:

Start -> Bet -> End

Start -> Deal -> End

Start -> 1st Deal -> End

Start -> 2nd Deal -> End References: ISTQB Certified Tester Foundation Level (CTFL) v4.0 sources and documents.