TDD stands for Test-Driven Development, or Test-Driven Design. It is the practice of writing a unit test before writing code to satisfy it, in what is known as the Red-Green-Refactor cycle.

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TDD for batch processing: How to do it?

I like "red/green/refactor" for RoR, etc. just fine. My day job involves batch processing very large files from third-parties in python and other custom tools. Churn on the attributes of these files ...
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End-to-end tests versus unit tests, should tests be decoupled?

At our company we typically make sure that we write an end-to-end test for our websites/web apps. That means we access a URL, fill in a form, submit the form to another URL and check the results of ...
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How do you keep your unit tests working when refactoring?

In another question, it was revealed that one of the pains with TDD is keeping the testing suite in sync with the codebase during and after refactoring. Now, I'm a big fan of refactoring. I'm not ...
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Is TDD viable in collaborative open source projects

Let's say I wanted to start an open source project that I hope/expect to have many people submit patches and whatnot. Is it viable to take a strict TDD approach? Can/should I expect/trust ...
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Single or multiple files for unit testing a single class?

In researching unit testing best practices to help put together guidelines for my organization, I've run into the question of whether it is better or useful to separate test fixtures (test classes) or ...
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How do I stress the importance of unit tests to my manager [duplicate]

I've recently started a new job, & I've been tasked with completing a feature that another developer didn't finish before he left the company. The existing tests are out of date (i.e ...
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How can I unit test audio?

I have inherited a small project and want to extend it and stabilize it at the same time by writing Unit Tests for all the new code I am adding. The first class, TypedAudioCreator, creates audio files ...
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Is it OK to introduce methods that are used only during unit tests?

Recently I was TDDing a factory method. The method was to create either a plain object, or an object wrapped in a decorator. The decorated object could be of one of several types all extending ...
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What to do when your colleagues don't value code maintainability [duplicate]

I've been working in the same software development department for a few years now. In that time, the average stay of a developer has been 6-9 months. A handful have been around for over 2 years, but ...
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Does TDD's “Obvious Implementation” mean code first, test after?

My friend and I are relatively new TDD and have a dispute about the "Obvious Implementation" technique (from "TDD By Example" by Kent Beck). My friend says it means that if the implementation is ...
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Designing unit tests for a stateful system

Background Test Driven Development was popularized after I already finished school and in the industry. I am trying to learn it, but some major things still escape me. TDD proponents say lots of ...
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Testing strategy for games

I've inherited a web-based educational game. Over the past year I've worked towards stabilizing the code and adding new features. Most of the logic is in the front-end, so back-end unit tests, while ...
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Relation between BDD and TDD

What is the relation of BDD and TDD? From what I understood BDD adds two main things over TDD: tests naming (ensure/should) and acceptance tests. Should I follow TDD during development by BDD? If ...
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How to do TDD for something with many permutations?

When creating a system like an AI, which can take many different paths very quickly, or really any algorithm that has several different inputs, the possible result set can contain a large number of ...
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Should I refactor my unit tests when I extract a class out of the System Under Test?

I wrote this class that does a few things (perhaps this is a violation of the Single Responsibility Principle). I realize now that some other part of the project needs a piece of that logic and the ...
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Static is bad, but what about the Factory pattern?

I'm on a TDD project, so I try to stick as much as possible to the good pratices involved with that kind of development. One of them is avoiding as much as possible static and global. I'm facing this ...
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TDD with SQL and data manipulation functions

While I'm a professional programmer, I've never been formally trained in software engineering. As I'm frequently visiting here and SO, I've noticed a trend for writing unit tests whenever possible ...
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Are there any scientific studies done on TDD that use total cost of ownership for a product as the measurement?

When I was reading the summary of previous work in Dogsa T, Batic D. The effectiveness of test-driven development: an industrial case study. Software Quality Journal. 2011;19(4):643-661. it struck me ...
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Methods for testing a very large application

I have a PHP app which is very large. There are usually 2-3 developers working on it full time and we are getting to the point where we are making changes and creating bugs (cough features!). The ...
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How do I do TDD on embedded devices?

I'm not new to programming and I've even worked with some low level C and ASM on AVR, but I really can't get my head around a larger-scale embedded C project. Being degenerated by the Ruby's ...
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When should I use mock objects?

I've read a lot of things about TDD but I still have doubts. For example, I have these class diagrams: It's a simple example, just to learn about TDD and mock objects. Which test should I write ...
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538 views

How to get initial API right using TDD?

This might be a rather silly question as I am at my first attempts at TDD. I loved the sense of confidence it brings and generally better structure of my code but when I started to apply it on ...
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Starting new project with TDD

I'm studying TDD and I read that it also helps you to define the design of the app, correct? So I decided to start creating a new project to help me understand it better. I want to create a simple ...
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How to TDD that the correct results are returned

I'm starting a new project, and trying very very hard to use TDD to drive the design. I've been pushing for years, and finally got approval to spend the extra time on this project to use it while I ...
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Is it a good idea to do TDD on low level components?

I'm considering writing a low level driver or OS components/kernels. The osdev.org folks seem to think that the important bits are not meaningfully testable this way, but I have read some discussions ...
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How do you efficiently keep your tests working as you redesign?

A well-tested codebase has a number of examples, but testing certain aspects of the system results in a codebase that is resistant to some types of change. An example is testing for specific ...
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How would type errors be detected while creating mocks in a dynamic language?

The problem occurs while doing TDD. After a couple of test pass, the return types of some class/module change. In a statically typed programming language, if a previous mocked object was used in the ...
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Why write tests for code that I will refactor?

I am refactoring a huge legacy code class. Refactoring (I presume) advocates this: write tests for the legacy class refactor the heck out of the class Problem: once I refactor the class, my ...
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TDD: Am I doing it right?

I'm a new programmer (only been learning for about a year) and in my goal to become better at it I have just recently learned about TDD. I wanted to get into the habit of using it since it seems very ...
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If TDD is about design why do I need it?

TDD gurus more and more tell us that TDD is not about tests, it is about design. So I know some developers who create really great design without TDD. Should they practice TDD then?
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How to do Test Driven Development

I have just 2+ years of experience in application development. In those two years my approach towards development was as following Analyze requirements Identity Core component/Objects, Required ...
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720 views

test driven development - Who should write the tests?

Originally, it is the duty of the developer to write the test, but I noticed that in many cases/e-mature developers those cases are not giving even 80% coverage. How about I have a QA person dedicated ...
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What is understood under “unit” in unit testing

As I understand in theory under "unit" people mean method (in OOP). But in practice tests which verify some method in isolation are very fragile behaviour tests (verifying not the result but the fact ...
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The Relative Cost Efficiency of (Acceptance) Test Driven Development

I would like to know what the overall impact of resource planning on a software project is, where the requirements and design of the project are driven by automated acceptance tests and unit tests, in ...
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What to do when TDD tests reveal new functionality that is needed that also needs tests?

What do you do when you are writing a test and you get to the point where you need to make the test pass and you realize that you need an additional piece of functionality that should be separated ...
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How does NUnit for C# compare with Unit Test facility integrated with Visual Studio

I need to work in a team to develop a mid scale Desktop application developed using C# .NET. Prior to this, I have not applied Unit Testing and Test Driven Development. I am aware that there exists ...
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In TDD should I have to write Test first or Interface first?

I am learning TDD using c#, as far as I know test should drive the development, that is first write a failing test after write the bare minimum code to pass the test then do refactoring. But it is ...
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How to unit test a function that is refactored to strategy pattern?

If I have a function in my code that goes like: class Employee{ public string calculateTax(string name, int salary) { switch (name) { case "Chris": ...
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How can I get started using TDD to code some simple functionality?

I basically have the gist of TDD. I'm sold that it's useful and I've got a reasonable command of the MSTEST framework. However, to date I have not been able to graduate to using it as a primary ...
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Is anyone doing “real” TDD with Visual-C++, and if yes, how do they do it?

Test Driven Development implies writing the test before the code and following a certain cycle: Write Test Check Test (run) Write Production Code Check Test (run) Clean up Production Code Check test ...
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A new name for unit tests

I never used to like unit testing. I always thought it increased the amount of work I had to do. Turns out, that's only true in terms of the actual number of lines of code you write and furthermore, ...
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Do you really have to do BDD/TDD in a test first manner?

Even though I haven't been in a TDD or BDD project, or I have been in some that say they are doing TDD but are pretty far from it, these are things that I think about and really try to read as much as ...
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How can I unit test a class which requires a web service call?

I'm trying to test a class which calls some Hadoop web services. The code is pretty much of the form: method() { ...use Jersey client to create WebResource... ...make request... ...do ...
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In TDD, if I write a test case that passes without modifying production code, what does that mean?

These are Robert C. Martin's rules for TDD: You are not allowed to write any production code unless it is to make a failing unit test pass. You are not allowed to write any more of a unit test than ...
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How to TDD test that objects are being added to a collection if the collection is private?

Assume that I planned to write a class that worked something like this: public class GameCharacter { private Collection<CharacterEffect> _collection; public void Add(CharacterEffect e) ...
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How to understand and debug legacy software? [duplicate]

Possible Duplicate: I’ve inherited 200K lines of spaghetti code — what now? Not long ago my company placed me in a team that deals with some of the most complex bugs that are in production. ...
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How to use unit tests as a source of information?

A colleague of mine was once at a seminar about agile development, where he heard it is possible to use unit tests as technical documentation. Something like using unit tests as an example of how to ...
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How do I check that my tests were not removed by other developers?

I've just came across an interesting collaborative coding issue at work. I've written some unit/functional/integration tests and implemented new functionality into application that's got ~20 ...
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Acceptance tests done first…how can this be accomplished?

The basic gist of most Agile methods is that a feature is not "done" until it's been developed, tested, and in many cases released. This is supposed to happen in quick turnaround chunks of time such ...
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TDD - what are the short term gains/benefits?

Quite often benefits of using TDD are considered as 'long term' gains - the overall code will be better structured, more testable, overall less bugs reported by customers, etc. However, where are ...