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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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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Testing ASP.NET .aspx and .ascx code behind files

I am wondering how to test .aspx.cs and .ascx.cs code behind. Can I use unit testing and if so how? Are there alternatives that will help test the functions in the code behind files? I don't know how ...
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Are there any cases when one should not use Test Driven Development? [duplicate]

Is it recommended that TDD be always practiced in a project, or are there cases when it should be avoided? Should we all adopt TDD? Is it standard practice in major software companies?
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If TDD is design, how do you know your TDD is well designed? [duplicate]

Given a large group (50+) of programmers: All given the same problem, All using Test-Driven Development (TDD), All pair programming, All doing group-based code review, I have personally seen the ...
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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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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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2answers
225 views

Characterization in Testing: Unit test or Functional test [duplicate]

So I'm trying to push for more automated testing in my company, which focus a lot on prototype and proof of concept systems. We currently use Google Test for unit testing. This tests specific test ...
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2answers
469 views

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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1answer
400 views

Test Driven Development Code Order

I am developing my first project using test driven development. I am using Zend Framework and PHPUnit. Currently my project is at 100% code coverage but I am not sure I understand in what order I am ...
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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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1answer
139 views

TDD verifying dependency method invoked correctly

I am trying to follow TDD in my proj but I can't get my head around how to verify I am calling a dependency correctly or even if I should be trying to verify it. Here's the requirement: Write an ...
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1answer
217 views

What kind of a test is a “consistency check”?

Some or all of the tests I write and run are checks for consistency e.g. assert that if I create a new user account, that the account that was created actually has the same name as the name that was ...
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Adding unit tests to brownfield applications [duplicate]

I'm working for a company that has been developing a series of products for years with little to no unit testing in place. They want to move to TDD and unit test new code going forward. However, I'm ...
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5answers
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Do I need a suite of unit tests for inner business-logic class? Since it's going to replicate the acceptance test suite for 90% [duplicate]

I'm new to TDD and wondering about methodolody. Given: A simple project which implements functionality of, for example, a console calculator. It has the following structure: Fairly simple top-...
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3answers
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Are “Stocks” a TDD/Unit testing anti pattern?

From Martin Fowler's Mocks Aren't Stubs he states that Stubs provide canned answers to calls made during the test while Mocks objects pre-programmed with expectations which form a specification of the ...
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12answers
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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 design/...
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14answers
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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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4answers
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Building complex algorithms with TDD

I'm trying to adopt TDD in my daily programming practice. I use it at work very effectively, but I'm having trouble with my personal projects where I'm using some complex algorithms. The particular ...
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2answers
169 views

When changing a class/method and you already have passing unit tests, should you change then test or write a test then change?

Say I have a class with a single constructor that accepts 2 parameters and initialises itself using those parameters. I have written tests for this and they are all passing. I later realise I need to ...
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5answers
876 views

Questions about TDD and unit testing

I am a junior software developer and I have been researching some of the practices in the industry to make myself better. I have been looking at unit testing briefly and I cannot see how the extra ...
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Is anyone doing “real” TDD with Visual-C++, and if yes, how do they do it? [closed]

Test Driven Development implies writing the test before the code and following a certain cycle: Write Test Check Test (run) Write Production Code Check Test (run) Clean up Production Code Check test ...
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9answers
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Do we need Logging when doing TDD?

When doing the Red, Green & Refactor cycle we should always write the minimum code to pass the test. This is the way I have been taught about TDD and the way almost all books describe the process. ...
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2answers
338 views

Testing Framework Selection: xUnit family theory

Background: I am familiar with xUnit family frameworks and have had experience with (shunit2, PhpUnit and simpletest). I am currently trying to find a testing framework for C++. I did a quick search ...
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8answers
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How to measure that a team is doing Test Driven Development

My team is considering a department goal of doing Test Driven Development next (fiscal) year. TDD sounds good and my manager is on board. The only problem is measurement. Our company rules require ...
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7answers
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Acceptance tests done first…how can this be accomplished?

The basic gist of most Agile methods is that a feature is not "done" until it's been developed, tested, and in many cases released. This is supposed to happen in quick turnaround chunks of time such ...
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Is it ever justifiable to write code without tests when doing TDD?

Is it ever justifiable to write production-code without also writing tests for it when doing Test Driven Development?
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715 views

How to TDD test that objects are being added to a collection if the collection is private?

Assume that I planned to write a class that worked something like this: public class GameCharacter { private Collection<CharacterEffect> _collection; public void Add(CharacterEffect e) ...
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Unit test SHA256 wrapper queries

I have the following SHA256 wrapper. public static string SHA256(string plainText) { StringBuilder sb = new StringBuilder(); SHA256CryptoServiceProvider provider = new ...
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348 views

On which abstraction level would you do TDD?

Problem I find myself nailing the class structure down by having too many unit tests which makes making changes hard. Example Assume we have a class A which uses classes B1 and B2. Class B1 uses ...
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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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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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2answers
296 views

TDD workflow for (implementation specific) edge cases

When developing features with TDD, I create a test for each combination of feature and case. So, one test for creating user successfully, one for validation errors, and one for database errors. I don'...
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TDD - Making assertions about C# Expression trees

How would you unit test the PerformUpdate method in the sample below? This is a (very) simplified version of some code that performs updates against a database where the schema is dynamic and ...
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7answers
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Is it sufficient to use acceptance and integration tests instead of unit test?

Short introduction to this question. I have used now TDD and lately BDD for over one year now. I use techniques like mocking to make writing my tests more efficiently. Lately I have started a ...
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What is an integration test exactly?

My friends and I have been struggling to classify exactly what is an integration test. Now, on my way home, I just realised, that every time I try to give a real world example of an integration test,...
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3answers
390 views

Debugging checklists: How much it's necessary to have? [closed]

Should making debug-checklists be an essential part of development process? How it can be integrated with unit-tests? Update Debugging checklist: Think about it as your troubleshooting checklist -- ...
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1answer
163 views

In TDD, is it bad practice to pass a test with code that would pass more than one test? [duplicate]

When using TDD, is it bad practice to pass a newly written test with code that could also pass another test? For example, take the following test (in PHP) public function ...
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How to test the data access layer?

I have a DAO method that utilizes Spring for JDBC access. It calculates a seller's success rate of selling an item. Here is the code: public BigDecimal getSellingSuccessRate(long seller_id) { ...
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6answers
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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 ...
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1answer
301 views

How do I test this?

I've attempted test first in Ruby on Rails using Test Unit and RSpec. I'm wondering how to do test first in situations that are more closely tied to the OS/filesystem. Problem: Building a USB stick ...
4
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1answer
673 views

Inheritance in test classes

I have an interface Serializer with methods serialize and isSerializerFor. I created a first implementation of this using TDD, and ended up with a nice clean test case fully covering a nice clean ...
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2answers
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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 ...
6
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1answer
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Managing false positives in TDD or BDD

I'm relatively new to TDD and have been thinking a lot about how to manage the perpetually growing pool of tests that comes with it. One of my biggest concerns is about false positives. In my ...
2
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2answers
333 views

How to refactor out static members of basic classes

Currently I am working on C++ project, which can be classified as "legacy" project. A lot of poor written code was committed because of lack of experience and under the pressure of deadlines. When I ...
6
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3answers
8k views

How do you unit test a User Interface? [closed]

I use JavaScript with JQuery for a Rails application. I have some dynamic behaviour in this one. As a Ruby developper, I like TDD/BDD, specialy with RSpec. For the moment, I test my JavaScript manualy....
24
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8answers
2k views

Are “TDD Tests” different to Unit Tests? [duplicate]

I read Stephen Walther's article about Test Driven Development (TDD) and unit testing. I think it was an excellent article. The author makes a distinction between what he calls "TDD Tests" and unit ...
2
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1answer
3k views

How to unit test a web client?

I am having a lot of trouble understanding how to unit test my web client. I have just finished a project using TDD for the first time - this project hd no external dependencies such as API calls or ...
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 ...
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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 ...
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2answers
670 views

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 -...