The Reality of Software Testing in an Agile Environment

Introduction:
The definition of agile testing can be described as follows: "Testing practice for projects using agile technologies, treating development as the customer of testing and emphasizing a test-first design philosophy. In agile development, testing is integrated throughout the lifecycle, testing the software throughout its development."*

Agile is a methodology that is seeing increasingly widespread adoption and it is easy to understand why-especially if you consider the developer and user point of view.

Users: Don't want to spend ages being quizzed in detail about the exact requirements and processes for the whole system, and then have to review a large specification, which they know could come back to haunt them.
Developers: Don't want to have to follow a tight specification, without any expression of their own imagination and creative talents, especially if they can see a better way.

Yet for the QA professional an Agile approach can cause discomfort - In the ideal world they would have a ‘finished' product to verify against a finished specification. To be asked to validate a moving target against a changing backdrop is counter intuitive. It means that the use of technology and automation are much more difficult, and it requires a new approach to testing, in the same way that it does for the users and the developers.

All the agile approaches have (at least) one characteristic in common in that they impact the role of the QA professional. This in itself is not a bad thing when the outcome is a step change for the better. However, when decisions are made on the basis of an invalid paradigm, change is not always analogous with progress. When a new paradigm is proposed for software development, by software developers, it is not a surprise that it is developer-centric. Abraham Maslow said that "He that is good with a hammer tends to think everything is a nail." The responsibility of the QA profession is not to bury its head and pretend that agile development will go away, it is our responsibility to engage in discussion to ensure that someone with a hammer is not pounding on a screw!

With the emergence of Test Driven Development** some suggest the role of QA is now questionable citing Test Driven Development (TDD) as the key to testing. But, what is most important is that QA is directly involved in the agile scrums all the way through, to be an integral part of the team designing the tests, at the same time as the requirements and solutions evolve.

QA teams need to know the real impact of an Agile methodology, there are boundless myths circulating the industry. Here is our reply to ten of our favorite myths:

Ten QA Myths Regarding Agile Testing.
There are a number of comments and statements regarding TDD and the QA function beginning to appear in articles on the internet by so-called specialists, that are, at best, misguided. This article responds to some of these myths and highlights challenges that QA teams will need to face up to and address in order to be successful in an increasingly agile world.

Myth One: "You only need to unit test - TDD testing is sufficient"
For the vast majority of commercial developments this simply isn't true. Even strong proponents of agile development recognize the need for their armory to include a range of testing techniques. For example, Scott W. Ambler has a list of 21 different testing techniques as part of his FLOOT (Full Life Cycle Object-Oriented Testing) methodology, including white box, black box, regression testing, stress testing and UAT. (http://www.ambysoft.com/essays/floot.html)

TDD programmers rely on these tests to verify their code is correct. If the requirements (test cases) are specified incorrectly, then you'll build robust code that fails to meet the objective.
Therefore, most agile projects include investigative testing efforts (black-box) which support rather than compete with white-box testing. Good investigative testing will reveal problems that the developer missed before they get too far downstream.

Myth Two: "You can reuse unit tests to build a regression test suite"
Some TDD proponents argue that conventional downstream testing is unnecessary because every line of application code has a corresponding test case; they suggest that by reassembling unit tests, everything from User Acceptance Tests to Regression Tests can be performed.

Although this sounds feasible, it isn't realistic, and here's why:
The granularity and objectives of white-box unit tests developed in TDD serve a different purpose from downstream black-box testing.

While the overall objective of a unit test is designed to prove that the code will do what is expected, the aim of regression testing is to ensure that no unexpected effects result from the application code being changed. These two objectives are not synonymous - e.g. checking that an attribute has a valid date format, is not the same as checking that for a given input, the value of the field contains an expected date.

Myth Three: "We no longer need testers, or automation tools"
Professional testers fulfill a different and equally valid role from their development colleagues.
It is widely recognized that traditional test automation tools have failed to live up to the hype of the vendors. Original Software's roots are as providers of products that improve the productivity of the database testing environment. It was because there were no adequate tools to provide User interface testing that we extended our solutions into this market sector; our heritage is aligned to effective testing rather than screen-scraping automation. When we developed TestDrive, we did it with the benefit of twenty years hindsight of missed opportunities from the traditional vendors.
Often, TDD projects have at least as much test code as application code and, therefore, are themselves software applications. This test code needs to be maintained for the life of the target application.

Myth Four: "Unit tests remove the need for manual testing"
Manual testing is a repetitive task; it's expensive, boring and error-prone. While TDD can reduce the amount of manual effort needed for functional testing; it does not, remove the need for further black-box testing (manual and automated).

By automatically capturing the tester's process and documenting their keystrokes and mouse-clicks, the tester will have more time for the interesting, value-add activities, such as testing complex scenarios that would be difficult or impossible to justify automating. Though manual testing is a time-consuming (and therefore expensive) way to find errors, the costs of not finding them are often much higher.

Myth Five: "User Acceptance Testing is no longer necessary"
Within agile development, acceptance testing is often positioned as working with the customer to resolve "incorrect requirements", rather than correcting functionality that does not map to what the user needs. When the user initially defines their requirements, they do it based on their initial expectations. When they see the system "in the flesh" they will invariably come up with different, or additional, requirements. While agile methods might reduce the frequency of this happening, it is unreasonable to expect the approach to resolve them entirely, so there should be no expectation that user acceptance testing will be obviated. This is especially true when it comes to the business user signing off approval of the User Interface, since they may have envisaged something different from the developer; which brings us nicely to myth six...

Myth Six: "Automation is impossible"
Automation in the early stages of an agile project is usually very tough, but as the system grows and evolves, some aspects settle and it becomes appropriate to deploy automation - automation that can cope with changes by using approaches such as self healing scripts.

To begin with, almost all testing from a user and QA perspective will be manual but this testing effort and design can be beneficial later if captured and re-used.

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