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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Do I need unit test if I already have integration test?

If I already have integration test for my program, and they all passed, then I have a good feel that it will work. Then what are the reasons to write/add unit tests? Since I already have to write ...
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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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Do unit tests sometimes break encapsulation? [duplicate]

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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Should I have unit tests for known defects?

If my code contains a known defect which should be fixed, but isn't yet, and won't be fixed for the current release, and might not be fixed in the forseeable future, should there be a failing unit ...
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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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How do I create an environment where fixing tests is seen as a priority?

I am a software engineer at a medium sized company. We have a fairly robust testing platform running on TeamCity. It does unit tests on every checkin, and a daily unit test/BVT run. The problem is ...
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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 ...
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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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Difficulties With TDD & Refactoring (Or - Why Is This More Painful Than It Should Be?)

I wanted to teach myself to use the TDD approach and I had a project I had been wanting to work on for a while. It wasn't a large project so I thought it would be a good candidate for TDD. However, I ...
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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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How can I use unit tests and TDD to test an app that relies mostly on database CRUD operations?

At work, one of my projects is mostly about taking data passed in from an external client and persisting it in a database. It's a Java enterprise app using JPA and most of our logic revolves around ...
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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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How to remove a function or feature when using TDD

In texts about TDD I often read about "remove duplication" or "improve readability" during the refactoring step. But what makes me remove an unused function? For example let's say there is a class C ...
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When should I write integration tests?

According to rules of TDD unit tests are written before production code, but what about Integration tests that exercises interaction between concrete (non mocks) wired objects? Should they be written ...
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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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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 ...
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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 ...
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Does TDD lead to the good design? [duplicate]

I'm in transition from "writing unit tests" state to TDD. I saw as Johannes Brodwall creates quite acceptable design from avoiding any of architecture phase before. I'll ask him soon if it was real ...
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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 granular should TDD tests be?

During TDD training based on medical software case we are implementing the following story: "When user presses Save button, system should add patient, add device and add device data records". The ...
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TDD and Version Control

I am currently learning about TDD and trying to put it into practice in my personal projects. I have also used version control extensively on many of these projects. I am interested in the interplay ...
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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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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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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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Good unit test examples for embedded C developers [closed]

I'm going to be giving a talk to my department next week about unit testing and test-driven development. As part of this, I'm going to show some real-world examples from some code I've written ...
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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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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 good unit tests to cover the use case of rolling a die?

I'm trying to get to grips with unit testing. Say we have a die which can has a default number of sides equal to 6 (but can be 4, 5 sided etc.): import random class Die(): def __init__(self, ...
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From a TDD perspective, am I a bad person if I test against a live endpoint instead of a mock?

I follow TDD religiously. My projects typically have 85% or better test coverage, with meaningful test cases. I do a lot of work with HBase, and the main client interface, HTable, is a real pain ...
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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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TDD and complete test coverage where exponential test cases are needed

I am working on a list comparator to assist sorting an unordered list of search results per very specific requirements from our client. The requirements call for a ranked relevance algorithm with the ...
15
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852 views

Software Testing Techniques or Categories [closed]

What kinds of software testing do you know? I've heard about Test-Driven Development, Unit tests etc, but can't understand their importance and difference. For example, why are we using regression ...
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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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Whats the real overhead of TDD once the entire team is used to it?

What percentage of time is saved and costed doing TDD. I assume this percentage of cost and reward changes during a projects life-cycle. I'd imagine the initial phase has a lot more cost but little ...
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Is there a modern replacement for a mutation testing tool like Jester for Java?

“Why just think your tests are good when you can know for sure? Sometimes Jester tells me my tests are airtight, but sometimes the changes it finds come as a bolt out of the blue. Highly ...
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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 ...
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TDD: What happens before the first unit test?

I mostly understand the theory of TDD, but I can't figure out how to get started. I sit down to write a unit test for a personal project and realize . . . I have no idea what I am testing. What ...
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What are the best resources for learning TDD? [closed]

I want to learn (and master) TDD. What are the best: books websites videos list of exercises personal words of wisdom for learning, appreciating, and using TDD?
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Is creating the objects you think you will need ok in a first test in TDD

I'm fairly new to TDD and I have trouble when creating my first test when it comes before any of the implementation code. Without any framework to the implementation code I am free to write my first ...
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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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Looking for Case Studies of How TDD Improved Quality and/or Speed of Development [closed]

At my company I am trying to make a case for why we should be doing TDD. Currently most developers just do whatever they can to get the project done, then go add unit tests after the fact in order to ...
14
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750 views

Do abstractions have to reduce code readability?

A good developer I work with told me recently about some difficulty he had in implementing a feature in some code we had inherited; he said the problem was that the code was difficult to follow. From ...
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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 ...
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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 ...
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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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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Should each unit test be able to be run independently of other tests?

Say you have tests for two methods of a class. The first method gathers data from another tier and puts it into some sort of storage independent of the runtime (such as a SQL table), so all of the ...
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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 ...