The Fundamentals of Software Testing

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“The Fundamentals of Software Testing” is the first module of the ISEB Foundation course and examination syllabus. ISEB recommends that Foundation students spend 20% of their study time on the Fundamentals course section. “The Fundamentals of Software Testing” is also the title of the opening chapter in the official ISEB Software Testing manual.

Understanding the fundamentals of ST is clearly crucial to achieving proficiency according to the ISEB professional standards. But what, precisely, are these “fundamentals,” and what do you need to know to pass the ISEB Foundation examination?

Why is it necessary?

According to Peter Morgan (freelance testing practitioner and member of the ISEB Accreditation and Examination panel), an unnecessarily high proportion of IT systems fail to fulfill expectations – or fail to work at all – because of insufficient ST before release.

 Fundamentals of Software Testing

Software testing cannot guarantee against software problems or even failure, but it can minimize the risk of faults developing once the software is in use. To understand why ST is necessary, it is important to consider the causes and impact of IT systems failure and the crucial role that testing plays in Quality Assurance.

  • The ISEB Foundation training-courses focus on five learning requirements:
  • o The potential impact of an IT systems failure;
  • o Causes/effects of software failure;
  • o Why testing is necessary;
  • o Testing versus Quality Assurance;
  • o Basic industry terminology.

What is it?

ST is a method of identifying faults in the product before it is released; this includes defects in the software code and its execution and any potential gap between what the code is supposed to do and what it actually does.

The ISEB Software Testing Foundation exam requires students to:

o Know the basic objectives of testing;

o, Understand how these objectives apply in the context of creating, using, and supporting software (including the difference between testing and ‘debugging,’ and the different uses of static testing and dynamic testing).

  • General principles
  • The ISEB courses introduce students to 7 software testing principles:
  • O Testing can show that problems exist, but not that problems do not exist.
  • O Testing covers a limited range of sample situations and is not comprehensive.
  • O The earlier a problem is found, the less it costs to fix.

O Defects will tend to cluster around specific areas (e.g., system complexity or staff inexperience). Testers can particularly target these areas.

  • O A set of tests, run repeatedly, will have a diminishing effect.
  • O The type, design, and focus of testing will vary according to the software tested.
  • O A test that does not reveal errors does not prove that the software is error-free.
  • Fundamental test process

Software testing is not simply a case of reviewing documentation or running a software program to check for bugs. To ensure that the appropriate tests are operated effectively and return value on the invested resources, software testers must carry out five basic activities, which the ISEB Software Testing guidance links to form a software testing process:

1. Test planning and control

a. Test planning defines what will be tested, how it will be tested, and who we will know when the testing is complete.

b. Test control is an iterative activity that compares the progress against the plan and adjusts it as required.

2. Test analysis and design

a. Test analysis considers the specific conditions to be tested and how these test conditions are to be combined into test cases.

b. Test design describes the test’s expected outcome so that testers can easily recognize when a fault has occurred.

3. Test implementation and execution

Execution represents the most visible testing activity and encompasses setting up the tests, generating test data, logging test activities, and analyzing the test results.

4. Evaluating exit criteria and reporting

The test “exit criteria” (established during “Test planning and control”) indicate that testing is complete.

5. Test closure activities

  • o Ensure that all documentation has been correctly completed
  • o Close down and archive the test environment, infrastructure, and test ware
  • o Hand over test ware to the maintenance team
  • o Log lessons learned
  • The psychology of testing

Selecting the appropriate individual(s) to perform the tests, and communicating the tests’ results to the developers, requires a basic understanding of the psychology of testers and developers.

The ISEB guidance provides a hierarchy of ‘independence.’ That is, a list of individuals who could potentially test the software, gradated according to their perceived level of detachment from the development process:

  • o The authors of the code
  • o Members of the same development team as the authors of the code
  • o A different group within the same organization
  • o A different organization

There are varying advantages and disadvantages to individuals at different levels in the hierarchy performing the software tests. For example, the developer might be able to resolve a difficulty more quickly but might also be less likely to spot the difficulties in the first place.

In addition to the independence/detachment of the testers from the software development process, it is important to consider how testers can communicate the test results to the developers. The ISEB Software Testing Foundation exam requires students to explain strategies for providing courteous feedback on defects, for example:

  • o Focus on delivering quality, rather than pointing out mistakes;
  • o Test reports are not directed towards people but products;
  • o Discuss problems openly, and attempt mutual understanding;
  • o At the end of a discussion, confirm that both parties understand what has been agreed.

Summary

Understanding the fundamentals is crucial to passing the ISEB Software Testing Foundation examination. During an accredited ISEB Foundation course, approximately two and a half hours should be devoted to studying what testing is, why it is necessary, and the fundamentals principles and processes behind a successful test performance.