ISTQB CTAL-TTA Practice Test - Questions Answers, Page 13

The term 'isolated' as a characteristic of a unit test means that it should test only the code for which it was originally written. This ensures that the unit test is focused, minimizes dependencies on other parts of the codebase, and errors can be traced back to specific units without ambiguity .

A unit test being 'deterministic' means that whenever it is run under the same conditions, it should produce the same results. This characteristic is crucial for reliable, repeatable testing outcomes that are not influenced by external factors or previous test states .

When a test class that validates a specific criterion (such as the minimum length of a password) fails, the immediate next step is to repair the failing code and re-execute the test. This approach adheres to the test-driven development (TDD) practices, where the cycle of writing a failing test, making it pass, and then refactoring is repeated. It ensures that each validation criterion is correctly implemented before moving on to additional functionalities or validations .

Service virtualization in the context of developing an e-shop application with an external payment gateway (still under development) offers significant benefits. It allows for realistic testing of the System Under Test (SUT) by simulating the behavior of the still-developing payment gateway, thus enabling testing to proceed without the actual service being available. Additionally, it simplifies the test environment by reducing the complexities associated with integrating and maintaining a live external service during development and testing phases .

The mnemonic FIRST is used to describe qualities of good unit tests in software development. Here, each letter stands for a critical attribute:

Fast: Tests should be quick to run.

Isolated: Tests should not depend on each other.

Reliable: Tests should consistently return the same results.

Self-Verifying: Tests should fully check their own results.

Timely: Tests should be written in a timely manner relative to the writing of the tested code. This mnemonic helps ensure that unit tests are effective and contribute positively to the development process .

Adopting an Acceptance Test-Driven Development (ATDD) approach can be particularly beneficial in scenarios where previous releases have suffered from misunderstandings among the development team and stakeholders regarding user story requirements. ATDD involves creating executable specifications before coding begins, which clarifies expectations and ensures alignment across the team. This method helps prevent issues seen in earlier stages by providing a clear, agreed-upon criteria for acceptance, thereby reducing the chances of future misunderstandings .

The pseudocode presented for review exhibits a likely issue with the control structure, particularly a missing else statement. This inference is drawn from the unbalanced opening and closing of conditional statements. The inner conditional structures suggest alternative outcomes based on several conditions, but the snippet likely misses an else statement associated with the condition lfb > 14, which could lead to ambiguous or unintended code behavior when lfb <= 14. Such issues can make the code difficult to maintain and could introduce bugs if not addressed. Ensuring each if has a corresponding else can prevent such potential errors in branching logic.

For Modified Condition/Decision Coverage (MC/DC), each condition within a decision must independently affect the decision's outcome. The provided sets of values need to be analyzed to ensure that each component of the decision ((A > B) or (C > D) and (E = F)) can independently influence the result of the combined expression. Set 3 includes variations for all variables that allow each condition to be tested both true and false independently while keeping the overall expression's outcome affected. This choice provides the most efficient path to achieving MC/DC with minimal tests.