Agile Test Driven Development [TDD]

Test Driven Development

Test Driven Development (TDD) is a software development program throughout which test cases are developed to define and validate what the code will do. In simple terms, test cases for every functionality are created and tested first and if the test fails then the new code is written so as to pass the test and making the code simple and bug-free. Test-Driven Development starts with designing and developing tests for each small functionality of an application. TDD instructs developers to write down new code as long as an automatic test has failed. This avoids duplication of code. the complete sort of TDD is Test-driven development.

Benefits of TDD:

-Much less debug time

-Code proven to satisfy requirements

-Tests become Safety Net

-Near zero defects

-Shorter development cycles

How to perform TDD Test:

Following steps define the way to perform TDD test,

-Add a test.

-Run all tests and view if any new test fails.

-Write some code.

-Run tests and Refactor code.

-Repeat.

Some clarifications about TDD:

• TDD is neither about “Testing” nor about “Design”.
• TDD doesn’t expect to “write a number of the tests, then develop a system that passes the tests.
• TDD doesn’t mean “do many Testing.”

What is acceptance TDD and Developer TDD

There are two levels of TDD

• Acceptance TDD (ATDD): With ATDD you write one acceptance test. This test fulfills the need for the specification or satisfies the behavior of the system. then write only enough production/functionality code to satisfy that acceptance test. The acceptance test focuses on the general behavior of the system. ATDD also was referred to as Behavioral Driven Development (BDD).
• Developer TDD: Beside Developer TDD we write a single developer test i.e. unit test then only enough production code to satisfy that test. The unit test adjusts to every small functionality of the system. Developer TDD is just called TDD.

The principal intention of ATDD and TDD is to specify detailed, executable conditions for your solution on a just-in-time (JIT) basis. JIT means considering only those requirements that are needed within the system. to increase efficiency.

It is the method where not an in depth specification of software/system is completed but exploring the wants of software/system which defines the general strategy of the project.

Test Driven Development (TDD)

• It boosts confirmatory testing of your application code and complete specification.
• Both acceptance tests (detailed requirements) and developer tests (unit tests) are inputs for TDD.
• TDD makes the code simpler and clear. It allows the developer to take care of less documentation.

Example of TDD

Here during this example, we’ll define a category password. For this class, we’ll attempt to satisfy the following conditions.

A condition for Password acceptance:

The password need should be between 5 to 10 characters.

First, we write the code that performs all the above requirements.

Scenario 1: To run the test, we perform class PasswordValidator ();

We will run the above class TestPassword ();

The output is PASSED as shown below;

Output:

Advantages of TDD

• Early bug notification.

-Developers test their code just within the database world, this usually consists of manual tests or one-off scripts. Using TDD you build up, over time, a set of automated tests that you simply and the other developer can rerun at will.

• Better Designed, cleaner, and more extensible code.

-It helps to know how the code is going to be used and the way it interacts with other modules.

-It leads to better design decisions and more maintainable code.

-TDD allows writing smaller code having single responsibility instead of monolithic procedures with multiple responsibilities. This makes the code simpler to know.

-TDD also forces to write down only production code to pass tests supported user requirements.

• Confidence to Refactor

-If you refactor code, there are often possibilities of breaks within the code. So having a group of automated tests you’ll fix those breaks before release. Proper warnings are going to be given if breaks are found when automated tests are used.

-Using TDD, should lead to faster, more extensible code with fewer bugs which will be updated with minimal risks.

• Good for teamwork

In the absence of any team member, other team members can easily devour and work on the code. It also aids knowledge sharing, thereby making the team simpler overall.

• Good for Developers

-Though developers need to spend longer in writing TDD test cases, it takes tons less time for debugging and developing new features. you’ll write cleaner, simpler code.

Summary:

-TDD stands for Test-driven development. it’s a process of modifying the code to pass a test designed previously.

-It more emphasis on production code instead of test suit design.

-Test-driven development may be a process of modifying the code so as to pass a test designed previously.