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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Test Driven Development for Complex Games

I'm coding a game in my spare time, but I am mostly still a beginner when it comes to programming. I'm sorry if this question is off topic or if it ends up not being helpful to anyone else, but ...
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4answers
166 views

How to identify and run the most relevant automated tests?

Suppose you have a reasonably large codebase (0.5 - 1 msloc) with a large test-suite (6-7hr single-threaded runtime; with a mix of unit-tests and integration-tests built with different tools). You ...
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1answer
74 views

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, ...
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46 views

Wrapping function in closures to make testable functions

In my nodejs project, I have functions like this for socketio. socket.on('draw', function (data) { socket.broadcast.to(socket.room).emit('draw', data); addEvent(socket, ["draw", data]); }); ...
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4answers
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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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120 views

acceptance test driven development in c++

Was put on hold at stack overflow: hopefully it has value here. I want to use a BDD / TDD / ATDD approach in c++. However I really want to emphasize vertical slices of end to end functionality rather ...
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66 views

Creating an Interface To a Language's Standard Library?

In the process of learning test-driven development, I've been introduced to dependency injection and the use of interfaces, and have started using these concepts in my own PHP code in order to make it ...
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2answers
160 views

Relationship between TDD and Software Architecture/Design

I'm new to TDD and have been reading the theory since applying it is more complicated than it sounds when you're learning by yourself. As far as I know, the objective is to write test cases for each ...
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1answer
68 views

How to unit test models in MVC / MVR app?

I'm building a node.js web app and am trying to do so for the first time in a test driven fashion. I'm using nodeunit for testing, which I find allows me to write tests quickly and painlessly. In this ...
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3answers
340 views

Designing unit tests for a stateful system

Background Test Driven Development was popularized after I already finished school and in the industry. I am trying to learn it, but some major things still escape me. TDD proponents say lots of ...
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105 views

How do you detect lying Stubs/Mocks?

Consider this piece of code from the PHPUnit manual(I'm using PHP only as an example): class StubTest extends PHPUnit_Framework_TestCase { public function testStub() { // Create a ...
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Using 2 Constructors: one that injects dependencies and one that instantiates them

I started using TDD for the first time on a project I started recently. I have a few objects with dependencies and structures that look something like this: public class MyClass { private ...
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120 views

Is there a name for this technique in testing? [closed]

When I've written tests for some code and want to make sure that it's actually testing what it's supposed to, I'll mess up or remove the code-under-test, and see if the tests fail. If they don't, I've ...
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156 views

Help in ensuring unit tests are meaningful

I've just written a unit test for this function, which loops through a collection of dates and sets properties equal to true or false depending on whether they're before or after a given comparison ...
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2answers
72 views

How to pick the testing values for parameterized tests for stateless functions?

When writing (parameterized) tests for stateless functions, how do I determine the most ideal set of values to test with? I'm writing a class with mathematical functions in C#, and I want to write ...
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2answers
182 views

How to know what to test in TDD? [duplicate]

I've heard about TDD more than one year ago, but until now I didn't manage to get myself started with it. Indeed, one of my greatest doubts is always what to test. The examples given always shows test ...
2
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3answers
135 views

How to test state of the object

I have a class DataImport with only two public methods public void fromStream(InputStream inputStream); public ImportCommand getImportCommand(); When I test it I send some test data to fromStream ...
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4answers
130 views

Implementing TDD for existing code [duplicate]

I've just been learning Unit Testing and I'm trying to understand how I could incorporate it with a project with existing code. Say I wanted to write tests for a specific class in that project, but ...
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2answers
200 views

Testing abstract class' behavior

I'm currently refactoring an existing design, which was created without TDD. There is a class hierarchy with one abstract base class and two subclasses. In the original design, these classes were ...
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5answers
424 views

DRY code, DRY tests?

At some point I had to create some class "Class1" and that class needs a method "method". So I have the following: Class1MethodTest: A total of N tests that check the behavior of Class1.method Class1 ...
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5answers
810 views

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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2answers
441 views

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 ...
4
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1answer
242 views

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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5answers
282 views

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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1answer
124 views

Which to implement first: GUI or backend? [closed]

So, I can code both, but which should I use a base for development? In terms of TDD, should minimal aspects in the GUI be used as the seed from which to grow towards backend logic? or should the ...
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2answers
201 views

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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114 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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699 views

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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1answer
78 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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6answers
772 views

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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0answers
47 views

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 ...
3
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5answers
200 views

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 ...
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3answers
407 views

Mocking static methods

Having recently returned from a Test Driven Development (TDD) course I had the following thought. While writing unit tests using Mockito we came up against of the problem of mocking static methods. ...
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4answers
205 views

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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1answer
120 views

Should a class validate argument using external method/service with unit testing?

I have a class that runs as a service and returns html code of a website when supplied with a URL. The code: public interface IHtmlDownloader { IWebProxy Proxy { get; set; } string UserAgent ...
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3answers
389 views

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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2answers
110 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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3answers
161 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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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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1answer
166 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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221 views

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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8answers
381 views

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 ...
2
votes
2answers
241 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 ...
20
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7answers
795 views

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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8answers
807 views

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, ...
10
votes
3answers
544 views

How do I stress the importance of unit tests to my manager [duplicate]

I've recently started a new job, & I've been tasked with completing a feature that another developer didn't finish before he left the company. The existing tests are out of date (i.e ...
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2answers
160 views

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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2answers
170 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 ...
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Looking for a specific Benefits of TDD Diagram [duplicate]

I'm looking for a specific diagram I saw recently. It was a combination of three diagrams, showing A project with Test First Unit Tests having less bug fix time / system testing A project with Test ...
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1answer
140 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 ...