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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Sporadic unittests or TDD?

I've read some basics about unit tests and TDD, but I find it hard to convince myself why TDD can have an advantage over only selected unittests. I've read common arguments for TDD, but don't see the ...
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Unit testing C++: What to test?

TL;DR Writing good, useful tests is hard, and has a high cost in C++. Can you experienced developers share your rationale on what and when to test? Long story I used to do test-driven development, ...
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3answers
117 views

Post-hoc testing in TDD recommended?

I have a personal project that doesn't have robust testing. I had a bit of TDD going on at the beginning, but it quickly became counterproductive as the project details changed dramatically over time. ...
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5answers
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What is a normal “functional lines of code” to “test lines of code” ratio?

I'm pretty new to TDD approach and my first experiments say that writing 1 line of functional code means writing about 2-3 lines of testing code. So, in case I'm going to write 1000 LOC, the whole ...
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Implementing unit testing at a company that doesn't do it

My company's head of software development just "resigned" (i.e. fired) and we are now looking into improving the development practices at our company. We want to implement unit testing in all ...
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test coverage reality

I am NOT doing test driven development and I write my test classes after the actual code is written. In my current project I have a test coverage (Line coverage) of 70% for 3000 lines of Java code. I ...
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4answers
851 views

Moving from mock to real objects?

I'm like doing TDD so I started everything mocking objects, creating interface, stubbing, great. The design seems to work, now I'll implement the stuff, a lot of the code used in the stubs are going ...
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4answers
281 views

Testing To Prevent Cascading Bugs

Yesterday, Twitter was hit with a "Cascading Bug" as described in this blog post: A “cascading bug” is a bug with an effect that isn’t confined to a particular software element, but rather its ...
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5answers
4k views

What are the design principles that promote testable code? (designing testable code vs driving design through tests)

Most of the projects that I work on consider development and unit testing in isolation which makes writing unit tests at a later instance a nightmare. My objective is to keep testing in mind during ...
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9answers
1k views

Are too many assertions code smell?

I've really fallen in love with unit testing and TDD - I am test infected. However, unit testing is normally used for public methods. Sometimes though I do have to test some assumptions-assertions ...
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10answers
2k views

Is 100% code coverage a pipe dream?

Is it feasible to expect 100% code coverage in heavy jquery/backbonejs web applications? Is it reasonable to fail a sprint due to 100% coverage not being met when actual code coverage hovers around ...
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4answers
452 views

Should you exercise TDD on prototype applications?

I'm developing an iOS app, which is a prototype for a customer. They're expecting it to not be of production standard and are happy for a few rough edges here and there. Since this is my first ...
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4answers
264 views

TDD: Write a separate test for object initialization or relying on other tests exercising it

This seems to be the common pattern that's emerging in some of the tests I've worked on lately. We have a class, and quite often this is legacy code whose design can't be easily altered, which has a ...
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5answers
489 views

Which class to start TDD of card game application? What's the next 5-7 tests?

I have started to write card game applications. Some model classes: CardSuit, CardValue, Card Deck, IDeckCreator, RegularDeckCreator, DoubleDeckCreator Board Hand and some game classes: Turn, ...
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1answer
440 views

How to unit test with lots of IO

I write Linux embedded software which closely integrates with hardware. My modules are such as : -CMOS video input with kernel driver (v4l2) -Hardware h264/mpeg4 encoders (texas instuments) -Audio ...
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2answers
817 views

Test Driven Development, has it reduced stress for developers?

I understand the benefits of test driven development, but have there been any studies that reveal the level of satisfaction with the product or stress levels of the authoring developers with the ...
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4answers
544 views

How do asserts and other error avoidance checks fit into TDD?

http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd You are not allowed to write any production code unless it is to make a failing unit test pass. So where do asserts fit into this? If ...
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8answers
1k views

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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2answers
385 views

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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5answers
395 views

How to use unit tests as a source of information?

A colleague of mine was one a seminar about agile development, where he heard it is possible to use unit tests as a technical documentation. Something like using unit tests as example how to use the ...
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3answers
258 views

TDD adding simple properties

I am currently doing my first real project with TDD. I have written tests, and implemented most of the logic for the application. However, there are properties I know I need to have on the UI, ...
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12answers
5k views

Has test driven development (TDD) actually benefited a real world project?

I am not new to coding. I have been coding (seriously) for over 15 years now. I have always had some testing for my code. However, over the last few months I have been learning test driven ...
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3answers
163 views

Test-driven development: To create test when issue is filed or when issue is picked up by somebody?

I've recently been working on a web development project on a team of less-than-five people. Things are going good but now we are decided to go with test-driven development. So far what I've learned ...
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4answers
723 views

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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2answers
584 views

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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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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355 views

How to conduct a 3 days training on current techniques like TDD and CI

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 ...
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6answers
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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 ...
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10answers
787 views

How to convince teammates to use TDD

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
755 views

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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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 ...
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If you had two projects with the same specification and only one was developed using TDD how could you tell?

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 ...
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2answers
833 views

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 ...
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10answers
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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 ...
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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 ...
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4answers
264 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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2answers
636 views

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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6answers
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How can I organize fast and comfortable solution compilation in VS 2010?

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 ...
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6answers
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What is the difference between BDD and TDD?

I have been learning writing test cases for BDD using specflow. If I write comprehensive tests with BDD is it necessary to write TDD test separately? Is it necessary to write test cases for both TDD ...
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What's a good name for a third type of testing?

I generally have different types of tests that I work with - the standard types: Unit Tests (testing basic functionality of classes, methods etc) and Integration Tests (testing how multiple components ...
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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 ...
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1answer
295 views

Looking for resources on TDD and BDD

I'm doing a presentation this week for Uni on the application of TDD and BDD. I'm trying to focus on types of code (such as algorithms, business logic or crud) and which methodology (if at any at all) ...
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11answers
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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
458 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 ...
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3answers
1k views

Is Test Driven Development in Javascript helpful for front-end developers?

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 ...
337
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12answers
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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 ...
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4answers
648 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 ...
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9answers
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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 ...
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511 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 ...