Category Archives: karlo

Tester or developer?

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In 1989. I started to learn my first programming language at high school. It was pascal. Unfortunately, we learned it by writing our programs on a sheet of paper , and when we had a computer lab scheduled for us we retyped those programs and executed them. In programs we had to implement various algorithms for creating various shapes by printing ‘*’ on computer screen. My primary learning goal was to understand those algorithms. At that time I didn’t know where to look for alternative learning materials. One of the reasons was that at that time I had been learning English language for just one year. But, there was one guy, Mirko, in my class that was a way ahead of me. He was taking about programming craft. He was self learner. He knew English language very well. 
Mirko: “Your are not finished with your program when you implement algorithm correctly. This is just the beginning. For example, you have also to consider memory consumption of your program.” 
At that moment I started my testing learning path.

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Finding testing none variables

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In video Dale Emery and Elisabeth Hendrickson demonstrated how to identify variables while exploring and use them to discover interesting things to test. As a demonstration they used Triangle Tester Exercise, application which determines based on user input for length of three triangle sides, is it possible to make valid triangle from those side values. Dale and Elisabeth listed possible testing variables for that application. I will list none testing variables.

None testing variables:

  • label for side input field
  • font type, size and color for information about the result of triangle side calculation algorithm. 
  • font type, size, color and background color for test data history header column. 
  • font type, size and color for input field. 
  • font type, size, color and background color for test data history column.
  • color, line and fill pattern for drawing for valid triangle.

To identify none testing variables is also important information because we can detect is this static data candidate to become variable if we look from the application user or tester perspective. For user application could become more usable, and tester could better test the application.
For triangle application example, input field fill color as a variable. Red fill for invalid input, bright red color for invalid input for color blind  users.
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Why just not test everything?

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I attended STP2010 conference  at Las Vegas. I was honored to meet Gerald M. Weinberg. I bought his book “Perfect Software: And Other Illusions About Software Testing” and got his autograph at the first page. I finally managed to read the book. And the next day at my work I started applying his advice’s in my project.
My current project is to check the implementation of Electronic Health Care Record (EHCR) that is based on CEN ENV 13606:2000 and HL7v3 standards. My first focus is to check the functionality of the EHCR module that implements that functionality.
CEN standard gives CRIUD (Create, Retrieve, Insert, Update, Delete) functionality to patient health record. Retrieve gives all the history of patient record, functionality very similar to version tree feature of modern version control systems, or only portion of the patient history, based on the query time constraint.
Complexity of CEN is in the xml implementation of the CRIUD functionality. Basic unit of CEN is archetype and datatype, and we support around two hundred of them (e.g. one is patient demographic data). Every delete and update creates version tree of particular archetype. CRIUD actions on archetype could be done by several roles (e.g. physician) defined by permission rules. In the end, basic combinatoric mathematics gives us infinite number of test cases (checks).
With budget constrains (time and money) we had to decide what to test (actually check). Talking with developers I wanted to get the insight how the EHCR module was designed. First, I found out that they wrote very good subsystem documentation (features, architecture and data model). Project issue with documentation is that there is no unique central document management system, so no one from test team didn’t know about that documentation. ehcr module uses a number of CEN xml schemas that do the first level of CEN xml message validation. Schema validation was coded using third party library (xerces). Based on that information we created several test cases to check that functionality and confirmed that errors in xml messages regarding defined schema were properly detected. The possibility in wrong error detection was only if schema is not according to requirements. But requirement analyst checked all xml schemas (about 200 of them) using advanced xml editor.
We put our focus on checking the requirements implementation that was coded by developers (various xpath expressions and if..then..else logic). Checking coded values (codes from database) was first check candidate. We found errors in those checks because developers did not understood the requirements (or requirements changed) and they did not coded them in business logic (missing xpath expressions and if..then..else logic).
The hardest part were hidden requirements of CEN protocol. You just have to understand CEN protocol which is not so simple. 
I will give one of the test cases. Demographic data contains three data items: mandatory date of birth and patient sex and optional date of death. Also, demographic data has its position in CEN (cen coordinates). Patient physician first creates demographic data with patient birthday and sex. After that inserts patient death date. He realizes that he made a mistake and deletes the death date. Patient changed its sex so physician updates patient sex and birthday. Now we have several versions of demographic data data items. Physician wants to update again birthday, but sends identification id (cuid) od sex data item instead of birthday. System reports an error code.
Another test case is when Physician updates whole demographic data, so whole demographic date info becomes obsolete.
So on system level we have an infinite number of such test cases.We discussed with developers those test cases in order to implement them in subsystem test because there are no any unit tests.  In that way developers narrowed down the infinite number of test cases because they know subsystem code and how to implement those checks on lower level.
We created automated jython scripts as system test, to test various and complex CRIUD functionality, for several randomly picked archetypes. There was a significant number of reported issues. After developers implemented subsystem checks and done code review base on our input, all issues were resolved. But important information was that there was no such issues when we checked other archetypes!
Testers had a problem of infinite number of checks for CRIUD CEN functionality. First, testers narrowed down the number of checks by checking only test cases that will be triggered in real usage of CEN protocol. What is real usage of CEN protocol, testers concluded based on real data gathered from the production subsystems that already gathered similar data.  They explained those test cases to developers, so developers could implement checks in subsystem code.

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Testers and user documentation

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On Software Testers Speak Up Meeting #1 I met a colleague tester that is responsible in his organization for writing user technical documentation. At that time, I was strongly against idea that testers should do that activity, because testers are responsible for testing the system. So my advice to the fellow tester was to convince his project manager that testers should stop writing project documentation.

But his response was that testers in his organization are the most qualified for writing user documentation, and user documentation is one of the most important artifacts of the agreement with the customer.

They had a situation when customer database administrator dropped production database, instead of applying a database patch (stupid mistake according to every database administrator that knows its craft). User documentation that explicitly stated how database patching should be done, played significant role when customer wanted to blame testers organization.

Because of that information I had been thinking for several weeks after testers speak up meeting. For testers organization, customer documentation is integral part of their product, not just the system itself!
So I decided to ask for help. Twitter was my tool of choice.

karlosmid Karlo Smid 

@michaelbolton I met a tester. He doesn’t do testing because he has to write customer documentation all the time. How should I advise him?

I know about Michael Bolton and his testing magic for a long time. I met him at the STP2010 in Las Vegas where I attended his Rapid Software Testing course. Great thing about him is that he is doing free consultancy. Here is his answer.

michaelbolton Michael Bolton 

@karlosmid When writing customer documentation, I did plenty of #testing. Often, I found way more bugs than “testers” did.

michaelbolton Michael Bolton 

@karlosmid So, for your friend: 1) NOTICE that you’re testing. 2) Report problems, give repro procedure, explain /why/ they’re problems.

And immediately all become clear. I had an emotion about testers writing user documentation. That emotion got me thinking about fellow tester problem. I asked for help, and advice was immediately clear: “As a tester, your are glue in your organization”. That means ask a lot questions about every line that you put in user documentation. When you write user documentation, interact with others, ask questions about documentation stuff that bothers you. Don’t be just a dummy that writes it down.

Today, there was also one important Michael tweet that connects with his advices about writing user documentation:

@michaelboltonMichael Bolton
Published: Shapes of Actions; why #testing is often described by oversimplified #Agile #PMP #PMI #PMOT #PMBOK

Read his blog post to further enhance your user documentation writing and questioning skills.

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