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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Should we always unit test bugs when correcting them?

When correcting bugs, it is encouraged where I work to first write a test that fails with the given bug, and then to fix the code until the test passes. This follows TDD practices, and is supposed to ...
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3answers
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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 ...
74
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16answers
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When is unit testing inappropriate or unnecessary? [duplicate]

It seems to be generally assumed (on Stack Overflow at least) that there should always be unit tests, and they should be kept up to date. But I suspect the programmers making these assertions ...
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3answers
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How to conduct a 3 days training on current techniques like TDD and CI [closed]

I am tasked to conduct a training for an upcoming team of 20 Java developers for a new project. The project owner wants us to use state of the art development techniques like TDD and CI. The ...
47
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7answers
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How to deal with static utility classes when designing for testability

We are trying to design our system to be testable and in most parts developed using TDD. Currently we are trying to solve the following problem: In various places it is necessary for us to use static ...
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3answers
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Real-world examples of apps written with TDD and good test coverage? [closed]

Are there any open source applications that are developed using test driven development that serve as models of how good unit testing should work? I'd prefer to see examples in C# and .NET. (Note ...
13
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10answers
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How to convince teammates to use TDD [closed]

I am the only person on my team that use TDD. How do I make them to use it? I am annoyed that when I pull, someone's code will break my tests and I am the one who has to fix them. Will using github, ...
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1answer
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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 ...
49
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16answers
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Why not write all tests at once when doing TDD?

The Red - Green - Refactor cycle for TDD is well established and accepted. We write one failing unit test and make it pass as simply as possible. What are the benefits to this approach over writing ...
39
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14answers
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If you had two projects with the same specification and only one was developed using TDD how could you tell? [closed]

I was asked this question in an interview and it has been bugging me ever since. You have two projects, both with the same specification but only one of these projects was developed using Test ...
4
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2answers
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How much extra time is needed to add unit test in a development task?

My team is considering moving to test-driven development. Currently we have almost no unit testing, we have been only relying on the user acceptance test, and developer's own manual test. Not everyone ...
42
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9answers
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Is unit testing or test-driven development worthwhile?

My team at work is moving to Scrum and other teams are starting to do test-driven development using unit tests and user acceptance tests. I like the UATs, but I'm not sold on unit testing for test-...
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11answers
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Do I need to test everything?

I'm going to start my first real project in Ruby on Rails, and I'm forcing myself to write TDD tests. I don't see real advantages in writing tests, but since it seems very important, I'll try. Is it ...
5
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4answers
287 views

Type mocking frameworks does not change coding practices from testability point?

Many people recommend that we should code against interfaces and avoid statics for testability. Interfaces are not just for testability, they are sometimes a requirement. But sometimes we introduce ...
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3answers
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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 ...
7
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6answers
2k views

How can I organize fast and comfortable solution compilation in VS 2010? [closed]

Most of programmers who are involved into development of more or less large project(s) know how annoying the process of compilation can be. There are some other things which are dependent on ...
217
votes
8answers
143k views

What is the difference between writing test cases for BDD and TDD? [duplicate]

I have been learning writing test cases for BDD (Behavior Driven Development) using specflow. If I write comprehensive tests with BDD, is it necessary to write TDD (Test Driven Development) test ...
70
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12answers
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New to TDD. Should I avoid private methods now?

I'm just now learning TDD. It's my understanding that private methods are untestable and shouldn't be worried about because the public API will provide enough information for verifying an object's ...
36
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11answers
2k views

How do people doing TDD handle loss of work when doing major refactoring

For a while I have been trying to learn to write unit tests for my code. Initially I started out doing true TDD, where I wouldn't write any code until I'd written a failing test first. However, I ...
5
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1answer
860 views

Node.JS testing with Jasmine, databases, and pre-existing code

I've recently built the start of a core system which is likely going turn into a monster product. I'm building the system with node.js, and decided after I got a small base built, that It'd be a ...
11
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2answers
2k views

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 ...
372
votes
12answers
14k views

Should I intentionally break the build when a bug is found in production?

It seems reasonable to me that if a serious bug is found in production by end-users, a failing unit test should be added to cover that bug, thus intentionally breaking the build until the bug is fixed....
3
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4answers
862 views

Development setup for TDD. Is it correct?

This is how my team has it's development environment set up: Each team member has a local development environment on their own computer, where they check out the code from a shared repository. Every ...
37
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10answers
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Should we test all our methods?

So today I had a talk with my teammate about unit testing. The whole thing started when he asked me "hey, where are the tests for that class, I see only one?". The whole class was a manager (or a ...
5
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4answers
592 views

How to Write Unit Tests When One Fix Will Make Many Failing Tests Pass?

I have two test cases to test a fix to code that is using the wrong criteria for selecting objects from a collection: Given one object in the collection matching the bad criteria, ensure that no ...
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8answers
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Advantages and disadvantages to making common unit test scaffolding code

For the project my team and me are working on we often find that we need large pieces of scaffolding code. Creating domain objects with correct values, setting up mocks for repositories, dealing with ...
4
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8answers
611 views

Emphasizing the importance of TDD to customers

The importance of TDD needs to be propagated but there's always a gap in the project timeline and time needed for developing a TDD project. Customers usually do not understand the importance of code ...
4
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4answers
220 views

How can I create Assert.AreEqual(myobject,somevariable) a test in TDD before writing production code?

Im researching TDD, I'm not really sure how to write a test before I have written production code. The problem is that TDD states that you make assertions and then write your code so that these ...
13
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6answers
4k views

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 ...
3
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4answers
219 views

Does not testing internals entail diligent refactoring and/or rely on developer talent?

I'm not asking here what the arguments are for/against testing internal methods (though I'll restate some, and don't mind hearing others). My questions relate to the implications of only testing ...
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2answers
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Should I use an aggregate root when designing my repository?

I have an entity that is called Master which is composed of a number of Slave entities. There can only be one Master in my database and I want to query repositories to get the Slave for a given id. ...
2
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2answers
276 views

Moving legacy application to a testable framework?

We have a web application which contains a web service with over 50 methods. The application is currently installed at a number of sites and is currently being maintained by one developer. The ...
47
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2answers
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What are the London and Chicago schools of TDD?

I’ve been hearing about the London style vs. Chicago style (sometimes called Detroit style) of Test Driven Development (TDD). Workshop of Utah Extreme Programming User's Group: Interaction-style ...
2
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2answers
464 views

How do you end up with event-sourcing if you use a xDD approach?

When working in a TDD or BDD manner your unit tests are supposed to drive your design. But how do you end up with event-sourcing using a xDD techniques? As I see it event sourcing is something you ...
14
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4answers
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Unit testing statically typed functional code

I wanted to ask you people, in which cases it makes sense to unit test statically typed functional code, as written in haskell, scala, ocaml, nemerle, f# or haXe (the last is what I am really ...
7
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3answers
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Getting from a user-story to code while using TDD (scrum)

I'm getting into scrum and TDD and I think I have some confusion which I'd like to get your feedback about. Let's assume I have a user-story in my backlog, in order for me to start developing it as ...
14
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4answers
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Why is Conway's “Game of Life” used for code retreats?

Code Retreat is an all-day training event that focuses on the fundamentals of software development. There's a "global" code retreat day coming up, and I'm looking forward to it. That said, I've been ...
20
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5answers
847 views

Does unit testing lead to premature generalization (specifically in the context of C++)?

Preliminary notes I'll not go into the distinction of the different kinds of test there are, there are already a few questions on these sites regarding that. I'll take what's there and that says: ...
13
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8answers
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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 ...
3
votes
1answer
96 views

How to deal with changes that need further testing while working on another test?

TDD means to test before you start writing production code. So I start writing a test for MyClass called MyClassTest. It fails and I start to implement the wanted functionality in MyClass. During the ...
3
votes
7answers
379 views

Steps towards TDD [duplicate]

I need some advice to take the steps for TDD. How do we think in terms of interfaces for everything when we are writing code? Most of the testing books tell you how to write tests. But I want a book ...
7
votes
4answers
331 views

How do I do TDD when expected behaviour is to be changed?

I've been doing TDD with a project I'm working on, and I have quite a large number of tests. I have quite a few automated tests around restrictions enforced in code, making sure things that shouldn't ...
44
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11answers
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What are the disadvantages of automated testing?

There are a number of questions on this site that give plenty of information about the benefits that can be gained from automated testing. But I didn't see anything that represented the other side of ...
19
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5answers
598 views

How can I start testing in a testing anticulture? [closed]

I have a confession to make: Formalized automated testing was never a part of my programming background. I now work in a very large company with many developers (most of them web developers of one ...
20
votes
6answers
1k views

Does adding unit tests make sense for well-known legacy code?

I'm talking about unit tests in the TDD sense. (Not automated "integration", or what you like to call it tests.) Legacy code as in: (C++) code without tests. (see: Michael Feathers' Working ...
12
votes
5answers
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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 ...
4
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2answers
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Which GOF design patterns work well with TDD, and which do not?

The GOF Design Patterns book rarely mentions the test-ability of each pattern. I'm aware that there are patterns such as Singleton that would lead to code for which it is difficult to write unit tests,...
4
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2answers
197 views

How to keep settings for C++ Unit Test modules in sync with the production code modules?

Note: I'm coming from a Windows / Visual-C++ background. Note: I have already read Michael Feathers' Working Effectively with Legacy Code. Note: Broad question, asking for narrow answers, i.e. while I ...
5
votes
1answer
571 views

Unit testing of “workflow” methods

We are currently developing a public API for our app. The methods on this public API are mostly putting together functionality in different corners of the system. An example would be: (names have been ...
0
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1answer
71 views

Verification naming confusion

According to Martin Fowler classical article, there are two types of verification: state and behaviour verification. At the same time I often see people telling about implementation vs. behaviour ...