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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Tools that can catch “fake coverage”?

Hypothetical scenario: codebase is exercised by unit tests run by a TeamCity build-bot, that also uses the built-in dotCover tool to provide coverage metrics. The build will fail if less than X% of ...
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Understanding unit tests/TDD for ASP.NET webforms [closed]

I'm the lead programmer at a small software firm (currently 4 developers including myself), we develop bespoke ASP.NET WebForms applications for businesses. I joined there in 2010 just after ...
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Write tests for unit tests in TDD?

In an answer to another question, I suggested creating a randomized value for input to a specific method. In my experience this has been useful for making tests more readable and it lets you skip the ...
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An alternative to requiring red in TDD: reverting code change?

According to this answer to this question, a good reason for always starting with a failing test ("Red") is to make sure that the test is working and that the code that will be written is what makes ...
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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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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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448 views

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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168 views

Testing that an attribute does not exist cannot fail when writing tests before code

I have been taught to follow the Red->Greeen->Refactor pattern when doing TDD. There have been situations where this pattern have not been applicable though. For instance, a test to make sure that a ...
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286 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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Is it possible to be agile without use cases and tests?

Rhetoric teaches us that the answer is probably yes. However I feel that we would no longer relate to the vast majority of Agile success stories. I think that my upper management read the benefits ...
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Test driven vs Business requirements constant changing

One of the new requirement of our dev team set by the CTO/CIO is to become test driven development, however I don't think the rest of the business is going to help because they have no sense of ...
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TDD: Where should I start?

I've read a lot about TDD and I've tried to develop using TDD without success ... I always stop staring at the screen... I've learned that I should not write tests for methods or class. I should ...
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Test driven development when implementing a flexible length list

According to the commonly used TDD strategy, to implement something, you write a test that fail the code first, write the simplest code, refactor, and then repeat. I am trying to imagine this scenario ...
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How to setup TDD environment

In TDD, is it good practice to keep the tests in the same directory as the code its testing or is it better separate the tests in either a different directory or a separate project. Would it be the ...
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190 views

How to test network connectivity API using TDD?

I'm currently trying to add TDD on my workflow. I fail to create tests where I can easily test a library that requires remote connections. More precise, my program uses snmp4j library. Currently I'm ...
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How to unit test image processing code?

I'm working in image processing (mainly OCR) and I wonder how I should integrate unit tests in my development. I'm already using unit tests for more "common" type of code but when dealing with image ...
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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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Is it ok to write “extra” unit tests?

My understanding of how TDD should work is that you write a failing test for the next bit of functionality you want to add to a function or object, code until the test passes and then write the next ...
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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. ...
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530 views

Testing-related methodologies except TDD/BDD [closed]

Are there any testing-related methodologies except TDD/BDD? I see a lot of people who practice their own testing approaches (e. g., see Ayende post), but I don't see any formalization for it, no ...
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370 views

How do you write tests for methods that interact with data in system files?

I'm trying to be proactive about writing an iOS app in a test-driven manner. However, I'm stumped as to how to test a method that is to interact with real system files. For those familiar with iOS, ...
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301 views

Unit Testing and .Net

Coming from a native development background, I'm used to my unit test runners outputting the file and line that caused the test failure. This allowed me to run the tests as a post-build step, and if ...
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663 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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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 ...
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643 views

How to test a method which is not as much as a unit, because it is more of a 'orchestrator' / 'process' / 'controller' / 'coordination' class [duplicate]

I want to test a method which is not as much as a unit, because it is more of a 'orchestrator' / 'process' / 'controller' / 'coordination' class. This is the case: I have four unit tested classes: ...
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Review tests first

I am going to adopt TDD in our team and one of the ideas I have is to review tests first. So one would write interfaces, mocks, and tests first, submit them for a code review and once interfaces and ...
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Test-Driven Design is not Unit Testing [closed]

Ran across this statement by Martin Fowler circa 2002: Unit testing in XP is often unlike classical unit testing, because in XP you're usually not testing each unit in isolation. You're testing ...
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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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Test Driven Development when the specifications change

These days, it's fairly common for me to be tasked to make a change that actually breaks the prior spec. I know that one of the major ideas behind TDD is to have a suite that verifies all your changes ...
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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 ...
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What if I can't make my unit test fail in “Red, Green, Refactor” of TDD?

So let's say that I have a test: @Test public void MoveY_MoveZero_DoesNotMove() { Point p = new Point(50.0, 50.0); p.MoveY(0.0); Assert.assertAreEqual(50.0, p.Y); } This test then ...
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Are injectable classes allowed to have constructor parameters in DI?

Given the following code: class ClientClass{ public function print(){ //some code to calculate $inputString $parser= new Parser($inputString); $result= ...
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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 ...
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Unit testing data access objects

I have recently started using test-driven development and unit testing, and it has paid off immensely in the areas where I have aplied it. One area that it has been helpful in is database access. When ...
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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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TDD in JavaScript [closed]

I'm about to participate in a Coding Kata and I would like to do it in JavaScript. What tools and libraries do I need for TDD in JavaScript?
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Newbie worried about CASE tool

I'm looking for some guidance on CASE tools and whether my concerns are valid. Recently I was in a meeting between my employer and an external software company which have a CASE tool currently in ...
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216 views

Going TDD in the middle of the project

They want us to develop new features of a product with TDD. I know that they don't usually write tests for legacy code of already developed modules. But yet, what if new features have to be added to ...
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211 views

Sprint Planning Meetings - determine if a work item is “planned”?

We've been working with Scrum for a while now, generally successfully. However of late, as the pressure has started to mount up we've encountered several situations where items came through planning ...
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How to implement isValid correctly?

I'm trying to provide a mechanism for validating my object like this: class SomeObject { private $_inputString; private $_errors=array(); public function __construct($inputString) { ...
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What is a “behavior rich object” and why would it be advantageous?

I am referring to the article Mocks aren't Stubs by Martin Fowler. When naming cases when he think "mockist" TDD will be advantageous, he said It's particularly worth trying if you are having ...
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How to decide what forms the System Under Test

Ok, so we started with the initial version of "The Art Of Unit Testing" and we do unit tests for classes where every test covers one aspect of one method. This has the drawback of high maintenance ...
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Is the difference between BDD and TDD nothing more than a vocabulary shift? [duplicate]

I recently made a start on learning BDD (Behaviour Driven Development) after watching a Google tech talk presented by David Astels. He made a very interesting case for using BDD and some of the ...
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Unit testing behaviours without coupling to implementation details

In his talk TDD, where did it all go wrong, Ian Cooper pushes Kent Beck's original intention behind unit testing in TDD (to test behaviours, not methods of classes specifically) and argues for ...
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Filling the gap between Conception and Unit Test

I am stuck trying to do TDD. I'd rather seek the counsel of others who have gone before rather than waste time with trial and error. QUESTION: What diagrams / exercises / development processes can ...
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Whose responsibility is it to create the interface and/or acceptance testing? Developer or QA?

I am a backend developer and always create tests for my applications. Recently I study and apply the interface tests (using selenium), but I doubted whether I who should create these tests, developer ...
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454 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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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 ...
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Product Owner and automated tests

One of the claims of BDD-style development is that it bridges the gap between Product Owner and developers: the Product Owner writes a story, which can be converted in an equivalent automated test ...
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Keep or discard tests that use methods now private [duplicate]

When writing object-oriented code from scratch, I try to follow these steps: Write a test that fails. Write a function that makes the test pass. When enough tests and functions are complete, ...