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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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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Does following TDD inevitably lead to DI?

I learned to do Test Driven Development (TDD), Dependency Injection (DI) and Inversion of Control (IoC) all at the same time. When I write code using TDD I always end up using DI in my class's ...
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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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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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Types of unit tests based on usefulness

From value point of view I see two groups of unit tests in my practice: Tests that test some non-trivial logic. Writing them (either before implementation or after) reveals some problems/potential ...
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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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TDD, new tests while old ones not implemented yet

I am experimenting with test-driven development, and I found that I often come to a following situation: I write tests for some functionality X. Those tests fail. While trying to implement X, I see ...
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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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Orthogonality of unit tests vs. concision of unit tests

I'm writing unit tests for a steering system for a video game. The system has several behaviours (avoid this area because of reason A, avoid this area because of reason B, each adding a bit of context ...
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Resources for Test Driven Development in Web Applications? [closed]

I would like to try and implement some TDD in our web applications to reduce regressions and improve release quality, but I'm not convinced at how well automated testing can perform with something as ...
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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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Should I write a test to prove that deleting code fixes a bug?

Occasionally I'll run into the situation where fixing a bug requires that I delete a section of code. The TDD purist would (I assume) advocate writing a failing test, deleting the code, then watching ...
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TDD with limited resources

I work in a large company, but on a just two man team developing desktop LOB applications. I have been researching TDD for quite a while now, and although it is easy to realize its benefits for ...
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Does test-driven development force me to follow SOLID?

I hear a lot from TDD practitioners that one of TDD's advantages is that it forces developers to follow SOLID principles (Single responsibility, Open-closed, Liskov substitution, Interface segregation ...
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How do I stress the importance of unit tests to my manager [duplicate]

I've recently started a new job and 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 useless)... ...
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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 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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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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Alternative to “Passing/Broken build” indicator?

When having a continuous integration executing the tests at each commit, a common best practice is to have all the tests passing at all times (aka "do not break the build"). I find some problems with ...
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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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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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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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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 output--...
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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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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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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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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 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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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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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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Is Test Driven Development in Javascript helpful for front-end developers? [closed]

I really need your advice. I'm reading a few articles about TDD in JavaScript but I'm really struggling to understand how to use it in my daily work. For instance I'm currently working on a page that ...
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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 and,...
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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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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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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 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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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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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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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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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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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 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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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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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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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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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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Why is it inappropriate to use UML diagrams to plan how your code will be organized?

So, yes, diagrams can be inappropriate at times. When are they inappropriate? When you create them without code to validate them, and then intend to follow them. There is nothing wrong with drawing ...
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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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Is wrapping a third party code the only solution to unit test its consumers?

I'm doing unit testing and in one of my classes I need to send a mail from one of the methods, so using constructor injection I inject an instance of Zend_Mail class which is in Zend framework. Now ...
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Cross-language Test-Driven Development

The short question: How do you follow Test-Driven Development on a project that spans multiple languages? Specifically, I'm writing a web application that uses JavaScript and PHP, and I want to ...