January 14, 2008

Evidence That Quality Has Everything To Do With Value

Posted by Ben Simo

“Quality is value to some person.”

Gerald Weinberg,
Quality Software Management – Systems Thinking

This morning, Jason Gorman's blog post title Proof That Value Has Little To Do With Quality? caught my attention. This title contradicts my definition of Quality. To me, Quality is all about value to stakeholders.

Quality is not about implementing the best development practices. Quality is not about writing solid code. Quality may not be about impressive features. Quality may have no relation to elegance. Quality may not even be reliable. Quality may be cheap or it may be expensive. Quality may be well planned or it may be haphazard.

Quality is all about value. Quality is about value to people that matter.

Jason references an interesting article about a web site that started as a learning exercise and "seems to come from the Anti-Perfectionist School of Design", yet is profiting its creator millions of dollars annually. In spite of many flaws, this web site is profitable because users find it valuable and users bring advertising dollars. I consider this to be a high quality web site in spite of its obvious flaws because it has value to people who matter. Instead of viewing this as an example of value having little to do with quality, I see this as a great example of Quality having everything to do with value. I suspect that Jason and I define Quality differently. This story is an example of how value sometimes has very little to do with all the other things we often call Quality.

Perhaps my thinking is too touchy-feely for those who think we need to measure and assure Quality through quantitative metrics and processes enforcement. By it's very nature, quality is subjective. Sometimes we can quantify the results of Quality: as in the $10 million in annual advertising profits. I suspect that some of you are subjectively estimating how better metrics and process might lead to better profits.

The real measure of Quality is a measure of value (not necessarily quantitative value) to those who matter.

"As professionals, we have no real control over the ultimate value of the software we create. And neither do our customers, or requirements analysts, or product owners, or whoever it is who's been charged with figuring out what the best use of the budget would be. It's all guesswork, like choosing lottery numbers or selecting which horse to bet on."
- Jason Gorman,
Proof That Value Has Little To Do With Quality?

While there is guesswork in determining who matters and what they value, it is not as random as selecting lottery numbers. Better understanding of who matters and what they value can help us reduce the guesswork. Ongoing dialog can bring better understanding. If Quality is nothing more than a lottery, then we might as well limit ourselves to BUFD and scripted manual testing.

Interactions, collaboration, and responding to our changing understandings can help us take control over Quality.

"Above all, listen to what your customers are telling you about Quality. ... Your customers are in a perfect position to tell you about Quality, because that's all they're really buying. They're not buying a product. They're buying your assurances that their expectations for that product will be met. ... Your customers may not have all the hard business facts. They may not be aware of your specs and your standards and your inspection reports ... They may not be able to give you a precise definition of Quality, but one thing's for certain -- they know it when they see it."

-John Guaspari,
I Know It When I See It: A Modern Fable About Quality

And, as Jason rightly points out, what satisfies users (and the business) today may not satisfy them tomorrow. Keep the dialog going.


January 11, 2008

Regular Expressions

Posted by Ben Simo

(bb|[^b]{2}); [Tt]hat is the \?\.

Regular expressions are great tools for testers. I have found them useful for describing GUI objects to GUI test automation tools. I have found them useful for automation results validation. I have found them useful for extracting data I care about from voluminous log files. I've also found them useful for manipulating data.

What are regular expressions? Regular expressions are patterns for finding text of interest. They are supported by many test tools, system utilities, text editors, and programming languages.

Regular expressions can include the following meta characters to define patterns.

  • ^ Matches the beginning
  • $ Matches the end
  • . Matches any single character
  • * Matches zero or more occurrences of the preceding character
  • \ Escape character
  • ? Matches zero or one occurrence of the preceding character
  • + Matches one or more occurrences of the previous character
  • [ ] Defines a character class
  • [^ ] Defines an exclusion-based character class
  • \{ \} Matches a specific number or range of instances of the previous character
  • \( \) Treats the expression between \( and \) as a group
  • | Or. Use to match one of many expressions
  • \< Matches the beginning of a word
  • \> Matches the end of a word
  • \b Word boundary
  • \B Not a word boundary

* Many tools do not support all meta characters

Here are some example regular expressions:

  • Matches “frog”, “bullfrog”, and “tree frog”; but not “Frog”

  • Matches “Froggy went a courting”, but not “Quality Frog”

  • Matches “frog”, “bullfrog”, and “tree frog”; but not “froggy” or “The frog sat on a log.”

  • Matches “cat”, “rat”, “bat”, “goat”, and “gnat”

  • Matches “2005”, “20005”, “20000000000000000000000005”, “25”; but not “2ABC5” or “2006”

  • Matches “Sped” and “Speed”; but not “Speeed”

  • Matches “2005” and “20005”, but not “25”

  • Matches “2005”, “2006”, “2007”, and “2009”; but not “2004”

  • Matches years 1990 through 2009.

  • Matches “1.29”, “1.29%”, and “1234.55”; but not “1.299” or “.29”

  • Matches any valid 2-letter US postal state or territory name abbreviation.

Want to learn more?

Take a look at my slides from last night's presentation to the Denver Mercury User Group. Check out Wikipedia. Or try a Google Search. If you ask bb|[^b]{2}, check out Think Geek.

Ha[p]{2}y T[ea]sting\.