ISTQB CTFL-2018 Practice Test - Questions Answers, Page 19

Gaining confidence about the level of the system's quality can be a common objective of testing, because testing can provide information about how well the system meets its specified requirements and user expectations, and how many defects have been found and fixed in the system.

This is an example of a failure, which is an event in which a component or system does not perform a required function within specified limits. In this case, the calculator software failed to perform the addition function correctly and gave an incorrect result.

Exploratory testing is by definition a reactive test approach, because it involves designing and executing tests based on the tester's knowledge, experience and intuition, and reacting to the actual behavior and feedback of the system under test. Exploratory testing does not follow a predefined test plan or test cases, but rather adapts to the situation and learns from the results.

To cover 100% statement coverage, we need to execute every statement in the code at least once. To cover 100% decision coverage, we need to execute every branch in the code at least once. The minimum number of test cases required to achieve both statement and decision coverage is 4 for statement and 5 for decision. Here is one possible set of test cases:

| Test Case | Input | Output | Statement Coverage | Decision Coverage | | TC1 | Walking = True, Midnight = False, Raining = False, Running = False | Take umbrella | S1, S2, S3, S4, S5 | D1-T, D2-T | | TC2 | Walking = False, Midnight = True, Raining = False, Running = False | Search light | S1, S2, S6, S7 | D1-F, D3-T | | TC3 | Walking = False, Midnight = False, Raining = True, Running = False | Take umbrella and search light | S1, S2, S6, S8, S9 | D1-F, D3-F, D4-T | | TC4 | Walking = False, Midnight = False, Raining = False, Running = True | Keep doing what you were doing | S1, S2, S6, S8, S10 | D1-F, D3-F, D4-F |

Regression testing is intended to find side-effects after changes have been applied to the system under test. Side-effects are unintended consequences of changes that may cause new defects or re-introduce previously fixed defects in parts of the system that were not directly modified. Regression testing can be done at any level of testing and can use any type of testing technique.

Black-box test techniques are test techniques that are based on an analysis of the test basis without reference to the internal structure of the system under test. Decision table testing is a black-box test technique that uses a table showing combinations of inputs and/or stimuli (causes) with their associated outputs and/or actions (effects). Use case testing is a black-box test technique that uses scenarios based on use cases (descriptions of sequences of events that a system performs that yield an observable result of value to a particular actor). State transition testing is a black-box test technique that uses models of the state transitions and events of a system to design test cases.

Static testing is testing of a component or system at a specification or implementation level without execution of that software. Requirements review is an example of static testing, because it involves checking the quality and completeness of the requirements specification document without executing the software.

The overall quality of the software can be increased by finding and fixing defects before releasing the software to the customers or users. A test case passes means that no defect was found in the tested functionality, which indicates a high quality. A test case fails, defect gets logged which subsequently gets fixed means that a defect was found and corrected, which improves the quality. Some tests are deferred because test environment is not available means that some functionality was not tested, which may leave some defects undetected, which reduces the quality. A bug is found but there is no corresponding test case means that a defect was found by chance or by other means than planned testing, which does not increase the quality of the testing process or the test coverage.

Both functional and structural approaches are used in integration tests.Functional testing verifies that the integrated components work together as expected, while structural testing checks the internal structure and logic of the integrated components1explains this in more detail:

Integration testing is a level of software testing where individual units are combined and tested as a group. The purpose of this level of testing is to expose faults in the interaction between integrated units. Test drivers and test stubs are used to assist in Integration Testing.

Integration testing can be done in two ways:

Bottom-up Integration Testing: Bottom up integration testing begins with unit testing, followed by tests of progressively higher-level combinations of units called modules or builds.

Top-down Integration Testing: In top down integration testing, the highest-level modules are tested first and progressively lower-level modules are tested after that.