DZone
Thanks for visiting DZone today,
Edit Profile
  • Manage Email Subscriptions
  • How to Post to DZone
  • Article Submission Guidelines
Sign Out View Profile
  • Post an Article
  • Manage My Drafts
Over 2 million developers have joined DZone.
Log In / Join
Refcards Trend Reports Events Over 2 million developers have joined DZone. Join Today! Thanks for visiting DZone today,
Edit Profile Manage Email Subscriptions Moderation Admin Console How to Post to DZone Article Submission Guidelines
View Profile
Sign Out
Refcards
Trend Reports
Events
Zones
Culture and Methodologies Agile Career Development Methodologies Team Management
Data Engineering AI/ML Big Data Data Databases IoT
Software Design and Architecture Cloud Architecture Containers Integration Microservices Performance Security
Coding Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Partner Zones AWS Cloud
by AWS Developer Relations
Culture and Methodologies
Agile Career Development Methodologies Team Management
Data Engineering
AI/ML Big Data Data Databases IoT
Software Design and Architecture
Cloud Architecture Containers Integration Microservices Performance Security
Coding
Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance
Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Partner Zones
AWS Cloud
by AWS Developer Relations
The Latest "Software Integration: The Intersection of APIs, Microservices, and Cloud-Based Systems" Trend Report
Get the report
  1. DZone
  2. Testing, Deployment, and Maintenance
  3. Testing, Tools, and Frameworks
  4. Sufficiency in Software Testing

Sufficiency in Software Testing

Preston Lee user avatar by
Preston Lee
·
Apr. 16, 08 · Interview
Like (0)
Save
Tweet
Share
8.17K Views

Join the DZone community and get the full member experience.

Join For Free

[img_assist|nid=2417|title=|desc=|link=none|align=right|width=100|height=124]When I was finishing up my B.S. I took a class in embedded software testing. The big assignment was to write the software that controls a single elevator, test the software to our satisfaction and deliver the whole shebang at the end of the semester. The critical lesson I learned from the course was not that the elevator software was difficult to write, but that there are an infinite number of odd and unfortunate events that could happen to any component involved, at any time, and there is no way to declare with 100% confidence that you have accounted for all possible defects.

So most software is not about perfection, but sufficiency. Everyones wants ultra-high quality, defect free wares, but at some point you must put down the keyboard and declare the product “sufficient” for release. Key problems: “How do you know when you’ve done enough testing?” And just as important, “When is the right time to test?”

This topic has been a open talking point at OpenRain. Marc is a strong proponent of many TDD/BDD principles and goes knife-throwing-freak-show when stuff isn’t well covered. (Ed. note: possible slight exaggeration… maybe.) I am also highly concerned with sufficient tests, but prefer a incremental approach and am wary to invest too much effort in automated tests up front for several key reasons.

  1. While development is underway, you incur unnecessary overhead to maintain tests developed before design stabilization. This overhead is inevitable during long-term maintenance, but the last thing I want to do on the project I started yesterday is refactor all my tests because I dropped a single column from the “users” table.
  2. When inexperienced developers write tests too early, they oft end up testing the dummy data and underlying framework, not your design. It is not our job as application-level developers to write test cases for all underlying dependencies, but since that’s all you have at the beginning of a project, it’s easy to waste time here.
  3. The benefits of writing tests first to flush out design details is diminished in dynamic languages. In Java, writing a quick block of pseudo-code to use your interface is a great way to explore your design from an “external” perspective. Once you’ve achieved design clarity, you can easily use your compiler errors to create correct interfaces. Dynamic languages such as Ruby, however, do not offer this compile-time help, lowering the benefit of the technique.  
  4. There’s no freaking way we’re checking in code that doesn’t compile. Sorry, but if I’m writing a Java unit test, there’s no way I’m putting up with 800 compiler errors (and no autocomplete) over the next day while I generate all my stubs. I don’t care if TDD says otherwise; it’s a stupid practice for statically typed languages.

Granted, if any of our systems crash, we probably aren’t going to irreparably harm anything except for my phone that goes flying across the room for ringing at 5AM, but we still have the issue of “sufficiency”. For OpenRain’s Rails-based applications, I’ve been using the following philosophies on a personal level.

  • Models tests should be implemented first and as soon as possible. Validation logic and other constraints should be verified up front, as key bugs here will likely effect other code. Add sample data as necessary.
  • Only functional/integration tests for core use cases should be done early. Adding too many upfront tests to the yet-to-stabilize design tends to add maintenance liability before it’s able to pay itself off.
  • Tests for non-core features should be tested shortly after a brief “breathing” period, wherein others can comment on the design/code before you’re fully committed to it. Don’t waste your time with a massive test suite until people stop telling you it sucks.
  • Avoid complex methods of testing. Multi-threaded and singleton-based designs have inherent testing complexities, and should be designed out if possible.
  • Aim for 100% coverage in dynamic languages. Otherwise you won’t catch retarded bugs like syntax errors.
  • Have all known, likely and anticipated issues resulting in a significantly negative state covered by an automated case. This is, perhaps, the crux of my “sufficiency” perspective. You must have some mental benchmark that determines when you are “done”. This does not imply that all issues are resolved, only that they are tracked and, hopefully, all the significant ones are fixed.

I’d love to hear your thoughts on practical testing philosophy. Please let me know what you think!

Software Software testing Testing

Opinions expressed by DZone contributors are their own.

Popular on DZone

  • Best Practices for Setting up Monitoring Operations for Your AI Team
  • How to Use Buildpacks to Build Java Containers
  • 4 Best dApp Frameworks for First-Time Ethereum Developers
  • What “The Rings of Power” Taught Me About a Career in Tech

Comments

Partner Resources

X

ABOUT US

  • About DZone
  • Send feedback
  • Careers
  • Sitemap

ADVERTISE

  • Advertise with DZone

CONTRIBUTE ON DZONE

  • Article Submission Guidelines
  • Become a Contributor
  • Visit the Writers' Zone

LEGAL

  • Terms of Service
  • Privacy Policy

CONTACT US

  • 600 Park Offices Drive
  • Suite 300
  • Durham, NC 27709
  • support@dzone.com
  • +1 (919) 678-0300

Let's be friends: