Unit testing is a method by which individual units of source code are tested to determine if they are fit for use.

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How should I test the functionality of a function that uses other functions in it? [duplicate]

Suppose there is a function get-data which returns a map of information about the id of the user passed in. now this function uses 3 functions source-a, source-b and source-c to get three different ...
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Staying OO and Testable while working with a database

What are some OOP strategies for working with a database but keeping things unit testable? Say I have a User class and my production environment works against MySQL. I see a couple possible approaches,...
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10answers
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How do you unit test private methods?

I am working on a java project. I am new to unit testing. What is the best way to unit test private methods in java classes?
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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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16answers
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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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7answers
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What should you test with unit tests?

I'm freshly out of college, and starting university somewhere next week. We've seen unit tests, but we kinda not used them much; and everyone talks about them, so I figured maybe I should do some. ...
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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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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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(Why) is it important that a unit test not test dependencies?

I understand the value of automated testing and use it wherever the problem is well-specified enough that I can come up with good test cases. I've noticed, though, that some people here and on ...
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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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5answers
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Would you rather make private stuff internal/public for tests, or use some kind of hack like PrivateObject?

I am quite a beginner in code testing, and was an assert whore before. One thing worrying me in unit testing is that is often requires you to make public (or at least internal) fields that would have ...
93
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18answers
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Are unit tests really that useful? [closed]

I just graduated with a degree in CS and I currently have a job as a Junior .NET Developer (C#, ASP.NET, and web forms). Back when I was still in university, the subject of unit testing did get ...
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Should we test all our methods?

So today I had a talk with my teammate about unit testing. The whole thing started when he asked me "hey, where are the tests for that class, I see only one?". The whole class was a manager (or a ...
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Databases and Unit/Integration Testing

I have had a discussion with someone about unit/integration testing with web applications and I have a disagreement about 1 core idea. The issues is that the person I am talking to think that the ...
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13answers
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Is it OK to have multiple asserts in a single unit test?

In the comment to this great post, Roy Osherove mentioned the OAPT project that is designed to run each assert in a single test. The following is written on the project's home page: Proper unit ...
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12answers
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How big does my project need to be for me to unit test it? [closed]

I assume that my project is decoupled enough to allow for unit testing. But how big, exactly, in terms of clases and functions does my project need to be to make unit testing worthwhile? We all make ...
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4answers
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When should I use mock objects?

I've read a lot of things about TDD but I still have doubts. For example, I have these class diagrams: It's a simple example, just to learn about TDD and mock objects. Which test should I write ...
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7answers
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How to Avoid Fragile Unit Tests?

We have written close to 3,000 tests -- data has been hard coded, very little reuse of code. This methodology has began to bite us in the ass. As the system changes we find ourselves spending more ...
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1answer
597 views

Unit testing for a scientific computing library

I've had a bit of experience with unit testing before, in what I call (not pejoratively) the classic software engineering project: an MVC, with a user GUI, a database, business logic in the middle ...
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4answers
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Unit testing internal components

To what extent do you unit test internal/private components of a class/module/package/etc? Do you test them at all or do you just test the interface to the outside world? An example of these internal ...
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1answer
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Is wrapping a third party code the only solution to unit test its consumers?

I'm doing unit testing and in one of my classes I need to send a mail from one of the methods, so using constructor injection I inject an instance of Zend_Mail class which is in Zend framework. Now ...
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7answers
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Difference Between Unit Testing and Test Driven Development

From reading the descriptions, I understand that in TDD tests are done prior to writing the function and in Unit Testing, its done afterwards. Is this the main difference, or the two terms can't even ...
61
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11answers
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Is static universally “evil” for unit testing and if so why does resharper recommend it? [closed]

I have found that there are only 3 ways to unit test (mock/stub) dependencies that are static in C#.NET: Moles TypeMock JustMock Given that two of these are not free and one has not hit release 1....
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11answers
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Is it a bad practice to modify code strictly for testing purposes

I have a debate with a programmer colleague about whether it is a good or bad practice to modify a working piece of code only to make it testable (via unit tests for example). My opinion is that it ...
42
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9answers
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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 test-...
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6answers
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How to explain the value of unit testing

I want to introduce the concept of unit tests (and testing in general) to my co-workers; right now there are no tests at all and things are tested by actually performing the tasks via the UI to see ...
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How should I test randomness?

Consider a method to randomly shuffle elements in an array. How would you write a simple yet robust unit test to make sure that this is working? I've come up with two ideas, both of which have ...
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7answers
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Automated unit testing, integration testing or acceptance testing [closed]

TDD and unit testing seems to be the big rave at the moment. But it is really that useful compared to other forms of automated testing? Intuitively I would guess that automated integration testing is ...
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5answers
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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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4answers
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Unit testing best practices for a unit testing newbie

In recent years, I have only written small components for people in larger projects or small tools. I have never written a unit test and it always seems like learning how to write them and actually ...
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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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4answers
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How to Quantify the Value of Unit Testing [duplicate]

Our organization is considering integrating unit testing into our software development workflow. I've heard lots of anecdotal stories about how it encourages better, easy to maintain, and well-planned ...
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Gradual approaches to dependency injection

I'm working on making my classes unit-testable, using dependency injection. But some of these classes have a lot of clients, and I'm not ready to refactor all of them to start passing in the ...
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5answers
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How should I unit test mathematical formulae? [duplicate]

I have a number of functions that are pretty close to the mathematical definition of a function. For example, a simplified version of one of these functions may look like: int function foo(int a, int ...
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10answers
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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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7answers
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best practice when unit testing for embedded development

I am looking for some best practice strategies for unit testing code written for embedded system. By embedded system, I mean code such as device drivers, ISR handlers etc., stuff that are pretty close ...
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11answers
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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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9answers
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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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8answers
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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 ...
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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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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 ...
16
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Coding and testing in the same sprint

How is testing handled within the same sprint as coding, if all or most of the coding is not done until the end of the sprint? (I'm referring to the "soup-to-nuts" development and testing of a single ...
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3answers
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Is it actually worth unit-testing an API client?

This is something that's been troubling me for a while now. Is it actually worth unit-testing an API client? Let's say you're creating a small class to abstract-away the calls to a petshop REST API. ...
2
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0answers
85 views

How to manage success dependency between unit tests [duplicate]

How do you manage the dependency of one unit test on another unit test succeeding? So, supposed I have a class and this class has say 5 methods. I create like 2 dozen unit tests (test methods) for ...
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6answers
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Why did Java make package access default?

I'm asking this question because I believe they did it for a very good reason and that most people do not use it properly, well from my experience in industry so far anyway. But if my theory is true ...
9
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3answers
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Unit testing vs Integration Testing [duplicate]

What is the difference between unit testing and integration testing when it come to web development (where 90-95% of the code relies on a database)? One thing I here all the time is that unit testing ...
7
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5answers
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How long should we generally spend writing unit tests for a new feature or bug fixing?

When I have to implement a new feature or fix a bug, I usually try to recreate the situation with a test. I sometime spend around 3 hours coming up with fixtures and writing the test. The actual ...
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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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Testing private methods as protected

I was reading this answer about testing private methods and it mentioned several possibilities: extract methods as public to another class make them public separate the env of test and production ...
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What are the design principles that promote testable code? (designing testable code vs driving design through tests)

Most of the projects that I work on consider development and unit testing in isolation which makes writing unit tests at a later instance a nightmare. My objective is to keep testing in mind during ...