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 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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Why does automated testing keep failing in my company?
We have tried to introduce developer automated testing several times at my company. Our QA team uses Selenium to automate UI tests, but I always wanted to introduce unit tests and integration tests. ...
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TDD vs. Productivity
In my current project (a game, in C++), I decided that I would use Test Driven Development 100% during development.
In terms of code quality, this has been great. My code has never been so well ...
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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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TDD negative experience
What is a negative side of your TDD experience? Do you find baby steps (the simplest fix to make test green) annoying and useless? Do you find no-value tests (when test has sense initially but in ...
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Why does TDD work?
Test-driven development (TDD) is big these days. I often see it recommended as a solution for a wide range of problems here in Programmers SE and other venues. I wonder why it works.
From an ...
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When is it appropriate to not unit test?
I work in a small company as a solo developer. I'm the only developer at the company in fact. I have several (relatively) large projects I've written and maintain regularly, and none of them have ...
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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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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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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 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 ...
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Does TDD really work for complex projects?
I’m asking this question regarding problems I have experienced during TDD projects.
I have noticed the following challenges when creating unit tests.
Generating and maintaining mock data
It’s hard ...
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How to test the tests?
We test our code to make it more correct (actually, less likely to be incorrect). However, the tests are also code -- they can also contain errors. And if your tests are buggy, they hardly make your ...
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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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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 ...
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Good example of complex code using TDD
What would be a good example of the use of TDD in large, real-life, complex, projects? All the examples I've seen so far are toy projects for the purpose of a book or a paper...
Can you name an ...
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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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How baby are your baby-steps in TDD?
Today we were training TDD and found the following point of misunderstanding.
The task is for the input "1,2" return sum of numbers which is 3. What I have written (in C#) was:
numbers = ...
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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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TDD - is it just about unit tests? [duplicate]
Do I understand it right that classical TDD is just about unit tests? Don't understand me wrong: I know the difference between TDD and just unit testing. I am asking whether it is correct to use ...
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Test driven development - convince me! [closed]
I know some people are massive proponents of test driven development. I have used unit tests in the past, but only to test operations that can be tested easily or which I believe will quite possibly ...
28
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4answers
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Always and only TDD
Test driven development. I get it, like it.
But writing tests does require overhead. So should TDD be used universally throughout the code base, or are there areas where TDD provides a high ROI and ...
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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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Can you be Agile without doing TDD (test driven development)?
Is is possible to correctly call yourself (or your team) "Agile" if you don't do TDD (Test-Driven Development)?
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I want to start using TDD. Any tips for a beginner?
I never used an automated test mechanism in any of my projects and I feel I'm missing a lot. I want to improve myself, so I have to start tackling some issues I've been neglecting like this and trying ...
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How should you TDD a Yahtzee game?
Let's say you're writing a Yahtzee game TDD style. You want to test the part of the code that determines whether or not a set of five die rolls is a full house. As far as I know, when doing TDD, you ...
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Unit testing newbie team needs to unit test
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 ...
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How should C++ Unit Test code be organized for maximum Unit Test efficiency?
This question is not about Unit Testing Frameworks.
This question is not about writing Unit Tests.
This question is about where to put the UT code written and how/when/where to compile and run it.
...
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How do we make unit tests run fast?
We have reached the point in our project where we have almost a thousand tests and people have stopped bothering with running them before doing a check in because it takes so long. At best they run ...
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Why is it often said that the test cases need to be made before we start coding? [duplicate]
Why is it often said that the test cases need to be made before we start coding?
What are its pros and what the cons if we don't listen to this advice?
Moreover, does that advice refer to black box ...
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What are the disadvantages of test-first programming?
It's all the rage nowadays. "Everyone" recommends it. That in and of itself makes me suspicious.
What are some disadvantages you have found when doing test-first (test-driven) development? I'm ...
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Writing the minimum code to pass a unit test - without cheating!
When doing TDD and writing a unit test, how does one resist the urge to "cheat" when writing the first iteration of "implementation" code that you're testing?
For example:
Let's I need to calculate ...
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How do you convince management to “invest” in unit tests?
How did you convince your manager to let you unit test?
By "use", I mean being allowed to develop, check-in to source control and maintain the unit tests over time, etc.
Typical management ...
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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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Automated Testing: Explaining its Business Value
To start I don't think this is a repeat of other questions on unit testing. What I'm looking for help with is articulating its value to a team of programmers, analysts, managers and testers. By ...
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Programming SOLID Principles
Over time I could understand two parts of SOLID – the “S” and “O”.
“O” – I learned Open Closed Principle with the help of Inheritance and Strategy Pattern.
“S” – I learned Single Responsibility ...
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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 ...
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TDD/Tests too much an overhead/maintenance burden?
So you've heard it many times from those who do not truly understand the values of testing. Just to start things out, I'm a follower of Agile and Testing...
I recently had a discussion about ...
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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: ...
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Are “TDD Tests” different to Unit Tests?
I read this article about TDD and unit testing:
http://stephenwalther.com/blog/archive/2009/04/11/tdd-tests-are-not-unit-tests.aspx
I think it was an excellent article.
The author makes a ...
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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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At what point would you drop some of your principles of software development for the sake of more money?
I'd like to throw this question out there to interestingly see where the medium is.
I'm going to admit that in my last 12 months, I picked up TDD and a lot of the Agile values in software ...
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What are the disadvantages of writing code before writing unit tests?
I have always seen the recommendation that we should first write unit tests and then start writing code. But I feel that going the other way is much more comfortable (for me) - write code and then the ...
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Do unit tests sometimes break encapsulation?
I very often hear the following: "If you want to test private methods, you'd better put that in another class and expose it."
While sometimes that's the case and we have a hiding concept inside our ...
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4answers
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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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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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Why is test driven development missing from Joel's Test?
I was reading this blog by Joel Spolsky about 12 steps to better code. The absence of Test Driven Development really surprised me. So I want to throw the question to the Gurus. Is TDD not really worth ...
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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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How are mock objects commonly misused?
I read an article recently which said that mock objects are often misunderstood and misused. Are there any clear mocking anti-patterns which I can look out for?
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how much time do you spend on Unit testing?
In a company I used to work for, executives insisted that the code coverage with unit tests must be 99% or more. This resulted in writing more tests than code. It took us literally 3 days to write ...
