Test Driven Development Interview Questions

What Is The Main Difference Between Bdd And Tdd

If TDD is about designing a thing right, Behavior-Driven Development is about designing the right thing. Like TDD, BDD starts with a test, but the key difference is that tests in BDD are scenarios describing how a system responds to user interaction.

While writing a BDD test, developers and testers are not interested in the technical details , rather in behavior . BDD tests are used to test and discover the features that bring the most value to users.

Is Unit Testing Worth The Effort

Unit testing is a vital part of the software development process. It helps to ensure that your code is functioning correctly and that your program meets all the requirements. Unit testing can also save you time and money in the long run by catching errors early on in the development process.

Overall, unit testing is definitely worth the effort. It may take some time to set up, but it will save you time and money in the long run. Plus, knowing that your code is functioning properly will give you peace of mind.

What Is A Mocking Library

A mocking library is a tool that helps create fake objects for testing purposes. These objects mimic the behavior of real objects and can be used to test how your code interacts with them. Mocking libraries are instrumental in unit testing, as they can help you isolate the code you are testing and avoid any possible side effects.

There are many different mocking libraries available, each with its own features and benefits. Some of Javas most popular mocking libraries are Mockito, EasyMock, and PowerMock. For .NET, there are also different options, but one of the most popular is the moq.

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Q: What Are The 3 Practices Of Bdd Ans:

Explain How Does A Test Coverage Tool Work

When software is being tested, the code coverage measures how much of the program’s source code is covered by the test plan. Code coverage testing runs in parallel with actual product testing. Using the code coverage tool, you can monitor the execution of statements in your source code. A complete report of the pending statements, along with the coverage percentage, is provided at the end of the final testing.

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What Is Api Testing

API testing is a type of software testing that focuses on the application programming interfaces that are used to communicate between different software systems. API testing can test applications that use APIs to communicate with each other and applications that expose APIs to be used by third-party developers.

The Manager Of Component ‘a’ Says His Functionality Is More Important Than That Of Component ‘b’ The Manager Of Component ‘b’ Says His Is More Important Than That Of Component ‘a’ You Can Only Implement One A Or B But Not Both

The key question to ask is definition of “IMPORTANT”. Is it important to the managers , important to the end consumer or important for Amazon. The first one needs to be thrown out immediately and the others must be quantified based on achievability, impact on end user and ROI.Less

If the rock were neutrally buoyant the water level would remain the same. It is heavier than water which causes it to displace more than its own volume while in the boat compared to at the bottom of the lake. Therefore the water level of the lake would go down.Less

These answers are troubling. The only correct answer so far is Ben. The water level goes down.Less

The weight of the boat plus you plus the rock has already displaced the height of the water. The only time the water level will change will be when the rock is mid air.Less

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+ Top Test Driven Development Interview Questions And Answers

Q1. What Are The Some Clarifications About Tdd?

• TDD is neither about Testing nor about Design.
• TDD does not mean write some of the tests, then build a system that passes the tests.
• TDD does not mean do lots of Testing.

Test-Driven development is a process of developing and running automated test before actual development of the application. Hence, TDD sometimes also called as Test First Development.

Q2. What Is Test Driven Development ?

Test-Driven Development starts with designing and developing tests for every small functionality of an application. In TDD approach, first the test is developed which specifies and validates what the code will do.

In normal Testing process, we first generate the code and then test . Tests might fail since tests are developed even before the development. In order to pass the test, the development team has to develop and refactors the code. Refactoring a code means changing some code without affecting its behavior.

Test Driven Development : Learn with Example

The simple concept of TDD is to write and correct the failed tests before writing new code . This helps to avoid duplication of code as we write a small amount of code at a time in order to pass tests. .

TDD cycle defines:

• Change code to make it right i.e. Refactor.
• Repeat process.

Q3. Should There Be Specific Tests For Logging In My Application?

Q4. Do All Unit Test Libraries Have To Be In Every Solution?

Q5. What Is The Primary Goal/benefit Of Unit Testing?

Early bug notification:

Whats The Difference Between Continuous Integration Continuous Delivery And Continuous Deployment

Continuous integration executes the sequence of steps required to build and test the project. CI runs automatically on every change committed to a shared repository, offering developers quick feedback about the projects state.

Continuous delivery is an extension of CI. Its goal is to automate every step required to package and release a piece of software. The output of a continuous delivery pipeline takes the form of a deployable binary, package, or container.

Continuous deployment is an optional step-up from continuous delivery. It is a process that takes the output from the delivery pipeline and deploys it to the production system in a safe and automated way.

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Can You Name Some Deployment Strategies

• Regular release/deployment: releases software to everyone at once, making it available to the general public.
• Canary releases: this is a method that reduces the chance of failure by exposing a small portion of the userbase to the release. With a canary release, developers gradually switch users to the latest release in a controlled way.
• Blue-green releases: consists of running two simultaneous instances of an application one is the stable version currently serving users and the other the latest release. Users are switched from the former to the latter all at once. This method is safer than the regular or big bang releases because users can instantly be routed back to the previous version if there is a problem.
• Dark launches: are deployments where new features are released without being announced. Features can be enabled in a very fine-grained way with feature flags.

Explain Test Scenarios Test Scripts And Test Cases In Software Testing

• Test Case: Test Cases are a series of actions executed during software development to verify a particular feature or function. A test case consists of test steps, test data, preconditions, and postconditions designed to verify a specific requirement.
• Test Scenario: Usually, a test scenario consists of a set of test cases covering the end-to-end functionality of a software application. A test scenario provides a high-level overview of what needs to be tested.
• Test Scripts: When it comes to software testing, a test script refers to the set of instructions that will be followed in order to verify that the system under test performs as expected. The document outlines each step to be taken and the expected results.

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You Have A 100 Coins Laying Flat On A Table Each With A Head Side And A Tail Side 10 Of Them Are Heads Up 90 Are Tails Up You Can’t Feel See Or In Any Other Way Find Out Which Side Is Up Split The Coins Into Two Piles Such That There Are The Same Number Of Heads In Each Pile

Split into two piles, one with 90 coins and the other with 10. Flip over every coin in the pile with 10 coins.Less

Pick 10 coins from the original 100 and put them in a separate pile. Then flip those 10 coins over. The two piles are now guaranteed to have the same number of heads. For a general solution of N heads and a total of M coins:1.) Pick any N coins out of the original group and form a second pile.2.) Flip the new pile of N coins over. Done.Example :Original group is HHTTTT . Pick any two of these and flip them over. There are only three possible scenarios:1: The two coins you picked are both tails. New groups are and when you flip the 2nd group you have and . 2.) The two coins you picked consist of one head and one tail. New groups are and and when you flip the 2nd group you have and .3.) The two coins you picked are both heads. New groups are and and when you flip the 2nd group you have and .Less

I politely tell the client who interrupted to please standby and that I will be able to answer their questions/handle their issues shortly. If they need immediate attention I will call a member of the team to assist.Less

1. calculate the sum of elements in array say SUM2. sum of numbers 1 to 100 is)/2 = 5050 when n==1003. missing element is Less

Common Ci/cd Interview Questions

Acing a CI/CD interview is all about preparation. Preparation starts with collecting as much information as you can about the prospective company, and their history, product, and interviewing process.

Next in the list is to brush up your technical skills because knowing your technical stuff will make you stand out. Questions are a great way of testing your knowledge. To help you, weve collected and answered 30 common CI/CD interview questions. How many can you answer?

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Q: What Is Example Mapping In Bdd Ans:

Example Mapping lets you explore and concentrate on the smallest pieces of behaviour in a story. In this way, you can pick out rules, identify the basis of a desired behaviour, and defer the rest of it. Using example mapping as a filter, you can prevent big fat stories from entering into your sprint and erupting with last-minute shocks three days before the demo day.

In addition, it saves time, which helps to keep the attention of busy product people in the process.

What Is System Testing

As its name implies, system testing is a type of testing that evaluates a system as a whole. This is in contrast to unit testing, which tests the individual components of a system. System testing is often used to assess the quality of a software product before it is released to customers.

System testing can be performed manually or using automated tools. Testers try to break the system to find bugs or errors when performing system testing. Once all the bugs have been fixed, the system can then be deemed ready for release.

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Have You Ever Used Test

Suggested approach: Hopefully the answer is yes, even if only a little, but remember to give examples. Did you use TDD/BDD fully, or did you occasionally write tests later on? Did you use it as part of a larger team? Did you find that it helped or hindered you from building a great product?

You might find it useful to talk about your approach specifically, because everyone is different.

Estimated difficulty: Intermediate

How Does Testing Fit Into Ci

Testing is integral to and inseparable from CI. The main benefit teams get from CI is continuous feedback. Developers set up tests in the CI to check that their code behaves according to expectations. There would be no feedback loop to determine if the application is in a releasable state without testing.

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Example Of Behavior Implementation In Bdd

Lets assume that we have a requirement to develop a login functionality for an application which has username and password fields and a submit button.

Step1: Write the behavior of the application for entering the username and password.

Scenario: Login checkGiven I am on the login page When I enter "username" usernameAnd I enter "Password" passwordAnd I click on the "Login" buttonThen I am able to login successfully.

Step2: Write the automated test script for this behavior as shown below.

@RunWithpublic class MyStepDefinitions     @When\" username$")    public void i_enter_something_username     @When\" password$")    public void i_enter_something_password     @When\" button$")    public void i_click_on_the_submit_button     @Then    public void i_am_able_to_login_successfully }

Step3: Implement the functional code .

public class LoginPage//store passwordpublic void enterPassword//match username and passowrd in db and return home pagepublic HomePage submit}}

Step4: Run this behavior and see if it is successful. If it is successful, then go to step 5 otherwise debug the functional implementation and then run it again.

Step5: Refactoring the implementation is an optional step and in this case, we can refactor the code in the submit method to print the error messages as shown in step 5 for the TDD example.

//match username and passowrd in db and return home pagepublic HomePage submitelse}else

Step6: Write a different behavior and follow steps 1 to 5 for this new behavior.

What Is Interaction

In software engineering, interaction-based testing is a technique for testing the behavior of a system by exercising its collaborations. That is its interactions with other systems.

Interaction-based testing focuses on specifying and verifying the behavior of a system in terms of its interactions with other systems. It is beneficial for testing systems that interact with other systems in complex ways, such as distributed systems.

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What Is A Mock

In software development, a mock is an object that simulates the behavior of another object.

You can also use mocks to verify that the unit of code under test interacts with the object or service in an expected way. For example, you can use a mock to verify that a method is being called with the correct arguments.

So, what is the difference between a stub and a mock? A stub only emulates the behavior of another piece of code and returns fake data. On the other hand, mock verifies that the desired behavior has happened.

Example Of A Test Case Implementation In Tdd

Lets assume that we have a requirement to develop a login functionality for an application which has username and password fields and a submit button.

Step1: Create a test case.

@TestPublic void checkLogin

Step 2: Run this test case and well get an error that says the Login page is not defined and there are no methods with names enterUserName, enterPassword and submit.

Step3: Develop the code for that test case. Lets write the underlying code which will enter the username and password and get a home page object when they are correct.

public class LoginPage//store passwordpublic void enterPassword//match username and passowrd in db and return home pagepublic HomePage submit}}

Step4: Run the test case again and well get an instance of the home page.

Step5: Lets refactor the code to give the correct error messages when the if conditions in the submit method, are not true.

//match username and passowrd in db and return home pagepublic HomePage submitelse}else

Step6: Now lets write a new test case with an empty username and password.

@TestPublic void checkLogin

Now if you try to run this test case, it will fail. Repeat steps 1 to 5 for this test case and then add the functionality to handle empty username and password strings.

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Is Unit Testing A White Box Or A Black Box Testing Technique

Unit testing is a white box testing technique. Unit tests have access to the inner workings of the units being tested. This allows for more comprehensive testing, as all unit parts can be tested. However, it also means that unit tests can be more challenging to write, as the developer needs to understand the code being tested.

What Is The Best Way To Set Priority For Test Cases In Testng

Prioritizing the order of your test methods can be accomplished by defining a priority order. Consequently, the test will execute in accordance with the priority set.

Syntax: @Test

Example: The following code demonstrates how to set the priority of a test case in TestNG.

package TestNG import org.testng.annotations.* public class SettingPriority @Testpublic void scalermethod2 @Testpublic void scalermethod3 }

Test Execution Sequence:

For example, here is a picture of a bug reported on Jira, a popular bug-tracking software.

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