Unit testing and Test Driven Development questions

Posted by Theomax on Programmers See other posts from Programmers or by Theomax
Published on 2012-09-23T09:25:28Z Indexed on 2012/09/23 9:48 UTC
Read the original article Hit count: 232

Filed under:

c#

|

unit-testing

|

TDD

|

asp.net-mvc

I'm working on an ASP.NET MVC website which performs relatively complex calculations as one of its functions.

This functionality was developed some time ago (before I started working on the website) and defects have occurred whereby the calculations are not being calculated properly (basically these calculations are applied to each user which has certain flags on their record etc).

Note; these defects have only been observed by users thus far, and not yet investigated in code while debugging.

My questions are:

Because the existing unit tests all pass and therefore do not indicate that the defects that have been reported exist; does this suggest the original code that was implemented is incorrect? i.e either the requirements were incorrect and were coded accordingly or just not coded as they were supposed to be coded?
If I use the TDD approach, would I disgregard the existing unit tests as they don't show there are any problems with the calculations functionality - and I start by making some failing unit tests which test/prove there are these problems occuring, and then add code to make them pass?

Note; if it's simply a bug that is occurring that can be found while debugging the code, do the unit tests need to be updated since they are already passing?

© Programmers or respective owner

Related posts about c#

.NET WebRequest.PreAuthenticate not quite what it sounds like

as seen on West-Wind - Search for 'West-Wind'
I’ve run into the problem a few times now: How to pre-authenticate .NET WebRequest calls doing an HTTP call to the server – essentially send authentication credentials on the very first request instead of waiting for a server challenge first? At first glance this sound like it should be easy:… >>> More
HttpWebRequest and Ignoring SSL Certificate Errors

as seen on West-Wind - Search for 'West-Wind'
Man I can't believe this. I'm still mucking around with OFX servers and it drives me absolutely crazy how some these servers are just so unbelievably misconfigured. I've recently hit three different 3 major brokerages which fail HTTP validation with bad or corrupt certificates at least according to… >>> More
Dynamic Type to do away with Reflection

as seen on West-Wind - Search for 'West-Wind'
The dynamic type in C# 4.0 is a welcome addition to the language. One thing I’ve been doing a lot with it is to remove explicit Reflection code that’s often necessary when you ‘dynamically’ need to walk and object hierarchy. In the past I’ve had a number of ReflectionUtils that used string based expressions… >>> More
The dynamic Type in C# Simplifies COM Member Access from Visual FoxPro

as seen on West-Wind - Search for 'West-Wind'
I’ve written quite a bit about Visual FoxPro interoperating with .NET in the past both for ASP.NET interacting with Visual FoxPro COM objects as well as Visual FoxPro calling into .NET code via COM Interop. COM Interop with Visual FoxPro has a number of problems but one of them at least got a lot… >>> More
Finding a Relative Path in .NET

as seen on West-Wind - Search for 'West-Wind'
Here’s a nice and simple path utility that I’ve needed in a number of applications: I need to find a relative path based on a base path. So if I’m working in a folder called c:\temp\templates\ and I want to find a relative path for c:\temp\templates\subdir\test.txt I want to receive back subdir\test… >>> More

Related posts about unit-testing

Unit testing best practices for a unit testing newbie

as seen on Programmers - Search for 'Programmers'
In recent years, I have only written small components for people in larger projects or small tools. I have never written a unit test and it always seems like learning how to write them and actually making one takes a lot longer than simply firing up the program and testing for real. I am just about… >>> More
About unit testing a function in the zend framework and unit testing in general

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello people, I am diving into the world of unit testing. And i am sort of lost. I learned today that unit testing is testing if a function works. I wanted to test the following function: public function getEventById($id) { return $this->getResource('Event')->getEventById($id); } So… >>> More
Unit testing a database connection and general questions on database-dependent code and unit testing

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, If I have a method which establishes a database connection, how could this method be tested? Returning a bool in the event of a successful connection is one way, but is that the best way? From a testability method, is it best to have the connection method as one method and the method to get… >>> More
What is the objective of unit testing?

as seen on Programmers - Search for 'Programmers'
I've been working with C# for the last 2 years, and I've never done any unit testing. I just need to know what the objective of unit testing is. What kind of results do we expect from unit testing? Is code quality checked by unit testing? In my view, unit testing is the job of testers; if that is… >>> More
Unit testing newbie team needs to unit test

as seen on Programmers - Search for 'Programmers'
I'm working with a new team that has historically not done ANY unit testing. My goal is for the team to eventually employ TDD (Test Driven Development) as their natural process. But since TDD is such a radical mind shift for a non-unit testing team I thought I would just start off with writing unit… >>> More