Is unit testing of software a waste of time?

 

Connecting state and local government leaders

The integration of testing into the coding part of the development lifecycle is a good thing, but don't go too far by fostering a brute-force, test-first and test-everything approach.

I’m currently working on a project that uses the JUnit framework for unit testing our software.  Unit testing is a method of testing software that focuses on testing small units of code like a single method or single class, which is a template for an object in object-oriented programming. 

Many modern integrated development environments will generate a stubbed out version of a unit test case for any class selected in a project.  Instead of throwing code over the wall to the testers at the end of development, the agile software development process considers testing, especially unit testing, as integral to the development process

The agile concept of writing unit tests first or taking a “test-first” approach was expanded and refined with the advent of the test-driven development process. TDD involves a very short development cycle where the test is created first, then the production code is written, refactored and cleaned until it passes the test. 

TDD and automated test frameworks (like JUnit) reinforced these new processes while riding the agile wave.  For years, no one dared question the new religion that myriad consultants pitched with zeal – until now.  Recently, David Heinemeier Hansson (the creator of Ruby on Rails), stated that TDD is dead

This “admission” followed several years of debate caused by a seminal paper by software guru James Coplien entitled, “Why Most Unit Testing is Waste.” At first blush, this appears to be yet another example of extreme programming (the progenitor of agile) overshooting its mark and needing to be pulled back from the edge by cooler heads. But Coplien’s paper makes several important points:

1.  Beware of testing for testing’s sake. One problem with unit testing is it cannot cover all the code to be tested, and therefore the tendency is to test what is easy to test.  Instead tests should be designed at the right level, which may mean system tests instead of unit tests.  It is easy to write a lot of useless tests, but good tests must be based on business requirements.  As Coplien says, “If this test fails, what business requirement is compromised?” 

2. Useless tests increase maintenance costs. The larger the code base (including both test and production code), the larger the maintenance costs.

3. Turn unit tests into assertions. Modern programming languages, like Java, allow assertions that enable developers to test assumptions in the code (like the assumption that “the value of X is 5”).  Assertions can also be turned off with a compiler switch and removed from production code although Coplien recommends they be kept in production code to automatically file a bug report on behalf of the end-user.

4. Good testing is hard and begs skepticism. Coplien concludes with the admonition to “be skeptical of yourself: measure, prove, retry.”  He bemoans the sloppy, fast-fail culture that exhibits overconfidence in the risk mitigation that unit-testing provides.  Being able to write unit tests fast and run them continuously does not improve risk mitigation. As Coplien says, “automated crap is still crap.”

Coplien’s well-reasoned paper caused a lot of soul searching in the agile community and David Heinemeier Hansson’s opening keynote at RailsConf 2014 (and blog post) stating that TDD is dead has spun up the debate and controversy.  Coplien debated TTD proponent Bob Martin on TDD.  More recently, Martin Fowler hosted a series of recorded hangout conversations between David Hansson and Kent Beck. 

Finally, Twitter exploded with the issue under the hashtag #tddisdead

So, what is the ramification for government IT managers of this new debate on the practice of unit testing and its agile incarnation, TDD? 

First and foremost is that the integration of testing into the coding part of the development lifecycle is a good thing.  Over-the-wall, Hail Mary passes to the testers are a practice that deserved an opposite reaction. However, don’t swing too far in the opposite direction by fostering a brute-force, test-first and test-everything approach. 

Instead, focus testing on key algorithms, system-level regression tests and well considered risk mitigation.  Focus testing on the failure and impact of key business requirements.  That is where the program will get the most bang for the buck in both the quality of the software and the maintenance budget.  So, while test-first may be on the ropes, automated testing is alive and well.  Long live testing!

Michael C. Daconta (mdaconta@incadencecorp.com or @mdaconta) is the Vice President of Advanced Technology at InCadence Strategic Solutions and the former Metadata Program Manager for the Homeland Security Department. His new book is entitled, The Great Cloud Migration: Your Roadmap to Cloud Computing, Big Data and Linked Data.

X
This website uses cookies to enhance user experience and to analyze performance and traffic on our website. We also share information about your use of our site with our social media, advertising and analytics partners. Learn More / Do Not Sell My Personal Information
Accept Cookies
X
Cookie Preferences Cookie List

Do Not Sell My Personal Information

When you visit our website, we store cookies on your browser to collect information. The information collected might relate to you, your preferences or your device, and is mostly used to make the site work as you expect it to and to provide a more personalized web experience. However, you can choose not to allow certain types of cookies, which may impact your experience of the site and the services we are able to offer. Click on the different category headings to find out more and change our default settings according to your preference. You cannot opt-out of our First Party Strictly Necessary Cookies as they are deployed in order to ensure the proper functioning of our website (such as prompting the cookie banner and remembering your settings, to log into your account, to redirect you when you log out, etc.). For more information about the First and Third Party Cookies used please follow this link.

Allow All Cookies

Manage Consent Preferences

Strictly Necessary Cookies - Always Active

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data, Targeting & Social Media Cookies

Under the California Consumer Privacy Act, you have the right to opt-out of the sale of your personal information to third parties. These cookies collect information for analytics and to personalize your experience with targeted ads. You may exercise your right to opt out of the sale of personal information by using this toggle switch. If you opt out we will not be able to offer you personalised ads and will not hand over your personal information to any third parties. Additionally, you may contact our legal department for further clarification about your rights as a California consumer by using this Exercise My Rights link

If you have enabled privacy controls on your browser (such as a plugin), we have to take that as a valid request to opt-out. Therefore we would not be able to track your activity through the web. This may affect our ability to personalize ads according to your preferences.

Targeting cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising.

Social media cookies are set by a range of social media services that we have added to the site to enable you to share our content with your friends and networks. They are capable of tracking your browser across other sites and building up a profile of your interests. This may impact the content and messages you see on other websites you visit. If you do not allow these cookies you may not be able to use or see these sharing tools.

If you want to opt out of all of our lead reports and lists, please submit a privacy request at our Do Not Sell page.

Save Settings
Cookie Preferences Cookie List

Cookie List

A cookie is a small piece of data (text file) that a website – when visited by a user – asks your browser to store on your device in order to remember information about you, such as your language preference or login information. Those cookies are set by us and called first-party cookies. We also use third-party cookies – which are cookies from a domain different than the domain of the website you are visiting – for our advertising and marketing efforts. More specifically, we use cookies and other tracking technologies for the following purposes:

Strictly Necessary Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Functional Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Performance Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Social Media Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Targeting Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.