Top Software Testing Interview Questions - Solved

Any kind of development needs testing. Wheather its web development, fron end, backend, data engineering pipelines or machine learning algorithms, everything must be tested properly before deployment. This page will explore interview questions around both manual and automation software testing. We encourage you to grasp these concepts and logics and do a hands-on before going for an interview.

Q:Can you explain the difference between black box testing and white box testing?

Two methods of software testing are used to assess the functioning and quality of a software system: black box testing and white box testing.

Black box testing is a testing method in which the tester is unaware of how the product being tested is implemented and operated internally. The tester only has access to the system's input and output; how it produces the output from the supplied input is irrelevant to them. Black box testing is primarily concerned with making sure the programme functions as intended and meets its functional criteria.

With white box testing, the tester is fully aware of the internal architecture and implementation of the software being tested. The tester can test both the functional requirements and the system's specific components and functionalities. The tester is truly interested in how the system generates the output from the provided input. The internal logic and structure of the software are the main topics of this examination.

Black box testing is helpful for testing a software system's functionality and exterior behaviour, whereas white box testing is advantageous for examining a software system's underlying logic and structure. To provide a full testing strategy, these approaches, which both have advantages and limitations of their own, are usually combined.

Q:Difference between a positive and a negative test case?

A test case is a set of conditions or variables that a tester will use to assess whether the system being tested satisfies the requirements or operates as intended. Test cases are frequently used to confirm that a system is operating as intended and to spot any flaws or problems.

There are two main types of test cases: positive test cases and negative test cases.

Positive test cases are meant to demonstrate that the system being tested is operating as planned and satisfies the required specifications. These test cases are used to confirm that the system operates as expected under typical or expected conditions and are predicated on the notion that the system is operating appropriately.

A successful test case for a website's login feature, for instance, would entail entering accurate login information and verifying that the user has successfully logged in. This test case determines whether the login process goes according to plan and enables users to access their accounts.

Negative test cases, on the other hand, are meant to show that the system under test can manage unexpected or incorrect input. These test cases are based on the assumption that the system is not functioning properly and are intended to verify that the system handles incorrect input or edge cases in an appropriate manner.

A negative test case for a website's login feature, for instance, can involve providing erroneous login information and confirming that the user is unable to log in. This test case is intended to verify that the login feature is operating properly and guarding against unauthorised account access.

A system's quality and dependability must be ensured using both positive and negative test cases. Negative test cases serve to detect any flaws or problems that may occur when the system is exposed to erroneous or unexpected input whereas positive test cases aid to verify that the system is operating successfully and satisfies the defined criteria.

It's important to note that both positive and negative test cases should be carefully planned and documented, and should include clear and specific steps for executing the test and verifying the results. Test cases should also be reviewed and updated regularly to ensure that they are still relevant and effective.

In conclusion, positive test cases are used to verify that a system is functioning as intended and fulfilling the requirements, whereas negative test cases are used to verify that the system successfully processes unexpected or invalid input. Both of these test cases should be thoroughly developed and recorded to ensure their efficacy because they are crucial for guaranteeing the quality and dependability of a system.

Q:Write a Python program to test the functionality of a simple login form using Selenium?


from selenium import webdriver
from selenium.webdriver.common.by import By

# create a webdriver instance
driver = webdriver.Chrome()

# navigate to the login form page
driver.get('https://example.com/login')

# locate the username and password fields and the login button
username_field = driver.find_element(By.ID, 'username')
password_field = driver.find_element(By.ID, 'password')
login_button = driver.find_element(By.ID, 'login_button')

# enter valid login credentials
username_field.send_keys('testuser')
password_field.send_keys('testpass')

# click the login button
login_button.click()

# verify that the user is successfully logged in by checking for the presence of a logged-in element
logged_in_element = driver.find_element(By.ID, 'logged_in')

# if the element is present, the login was successful
if logged_in_element:
print('Login successful!')
else:
print('Login failed')

# close the browser
driver.quit()

This software launches a web browser and navigates to the login form page using Selenium. The find element method and the By class are then used to locate the login button, username, and password fields in the website. It clicks the login button after entering accurate login information in the forms.

Finally, it looks for a page element (such a "logged in" message or a link to the user's profile) that is only visible when the user is logged in. The application prints a message to the console and indicates that the login was successful if the element is present. If the component is missing, the login attempt fails and a separate message is printed by the software.

This is really a straightforward illustration, but it shows how Selenium may be used to automatically test and validate the operation of a login form.

Q:What is the difference between integration testing and unit testing?

The two methods of software testing, unit testing and integration testing, are used to test various components of a software application.

Unit testing is a sort of testing that entails testing particular software application units or components separately from the rest of the application. Unit testing aims to confirm that each component of the software programme functions as intended and complies with all criteria. Unit tests are frequently brief and concentrate on verifying a single function or technique. Normally automated, they check that the application is operating properly after each update to the code.

Integration testing, on the other hand, is a type of testing that involves testing the interaction and communication between different units or components of a software application. The goal of integration testing is to validate that the different units of the software application work together as intended and can exchange information and data correctly. Integration tests are usually larger in scope than unit tests and involve testing the integration of different units or components of the application. They are also usually automated and run every time the code is changed to ensure that the application is working correctly.

In summary, unit testing is focused on testing individual units or components of a software application in isolation, while integration testing is focused on testing the interaction and communication between different units or components of the application.

Q:Write a Python program to test the performance of a web application using JMeter?

Python program that uses the pyjmeter library to create a JMeter test plan and run a performance test on a web application is as below:

First we will import os and JMeter, then we will set number of threads (users) and the ramp-up period (in seconds) along with base URL.

import os

from pyjmeter import JMeter

base_url = "http://example.com"

threads = 100
rampup = 60

# Create a JMeter test plan
testplan = JMeter.TestPlan(name='Performance Test')

# Create a HTTP Request sampler to test the web application
http_request = JMeter.HTTPSampler(name='HTTP Request',
domain=base_url,
path='/',
method='GET')

# Add the HTTP Request sampler to the test plan
testplan.add_user_defined_variables(http_request)

# Create a thread group and add the HTTP Request sampler to it
thread_group = JMeter.ThreadGroup(name='Thread Group',
num_threads=threads,
ramp_time=rampup)
thread_group.add_sampler(http_request)

testplan.add_thread_group(thread_group)

# Create a listener to view the test results
summary_report = JMeter.Summariser(name='Summary Report')
testplan.add_listener(summary_report)

# Run the test plan
JMeter.run(testplan)

This program creates a JMeter test plan with a single HTTP Request sampler that sends a GET request to the root URL of the web application. It then creates a thread group with the specified number of threads and ramp-up period, and adds the HTTP Request sampler to the thread group. Finally, it adds a summarizer listener to the test plan to view the test results. When the test plan is run, JMeter will send the specified number of requests to the web application in parallel, and measure the response times and other performance metrics.

You can modify this test plan by adding more HTTP Request samplers to test different pages or functionality of the web application, or by adding other types of samplers, like JDBC samplers or JMS samplers, to test database or message queue performance. You can also add assertions to the test plan to verify the response data, or add listeners to save the test results to a file or view them in a graph.

Q:Explain the difference between a test plan and a test case?

Test plan and test case are two different concepts in software testing. A test plan is a document that outlines the testing strategy for a software application. It specifies the scope, objectives, resources, and schedule of the testing process. A test plan typically includes the following elements:

Introduction: An overview of the test plan's objectives and parameters is provided in the introduction.

Objectives: The precise aims and purposes of the testing procedure, such as identifying flaws, confirming functionality, or gauging effectiveness.

Scope: The scope of the test includes both the portions of the software programme that will be tested and those that won't.

Approach: The approach, which might include manual testing, automated testing, or a combination of both, is the overall plan and process for testing the software application.

Resources: The people, equipment, and software that will be required for testing, including the testing environment, the testing data, the testing tools, and the testing equipment.

Schedule: The start and conclusion dates, as well as the length of each testing phase, are included in the testing process's timeline and milestones.

Risks and assumptions: The assumptions and dangers that might affect the testing process, as well as the backup strategies for handling them.

Deliverables: the test-related paperwork, including reports, records, and other products.

On the other hand, a test case is a predetermined set of test inputs, anticipated results, and execution procedures for testing a particular software application feature or behaviour. A test case typically includes the following components and is created to test a particular requirement or feature of the software application:

Test case ID: A unique identifier for the test case.

Test case name: A brief description of the test case.

Prerequisites: Any setup or preparation that needs to be done before the test case can be executed.

Test steps: The detailed steps to execute the test case, including the input data and expected results for each step.

Test data: The data and values that will be used as input for the test case.

Expected results: The expected output or behavior of the software application after the test case is executed.

Actual results: The actual output or behavior of the software application after the test case is executed.

In summary, a test plan is a high-level document that outlines the overall strategy and approach for testing a software application, while a test case is a detailed set of instructions for testing a specific feature or functionality of the software application.

Q:Write a Python program to test the security of a web application using Burp Suite?

Python program that uses the requests library and the Burp Suite API to test the security of a web application:

We will first set the URL and then will set the api endpoint of burpsuite.


import requests

url = "https://www.example.com"

burp_api_endpoint = "http://127.0.0.1:8080"

burp_api_key = "your-api-key-here"

headers = {
"X-Api-Key": burp_api_key,
"Content-Type": "application/json"
}

payload = {
"url": url
}

response = requests.post(f"{burp_api_endpoint}/v0.1/scan", json=payload, headers=headers)

if response.status_code != 200:
print("Error: API request failed")
else:
# Parse the response data
data = response.json()

# Check the scan status
if data["status"] == "running":
print("Scan is still running")
elif data["status"] == "complete":
print("Scan complete!")
print("Number of issues found:", data["issue_count"])
else:
print("Error: Unknown scan status")

This code sends a scan request to the Burp Suite API, which will scan the specified web application for security vulnerabilities. The response from the API includes the scan status and the number of issues found.

Note that you will need to install the requests library and have Burp Suite set up and running on your machine in order to use this code

Q:Can you explain the difference between regression testing and smoke testing?

Software testing techniques like regression testing and smoke testing are used to confirm a software application's dependability and stability.

Regression testing is a type of testing used to make sure that adjustments or alterations made to a software programme have not resulted in the introduction of any new flaws or issues. Regression testing is frequently carried out following modifications to the software, such as the addition of new features or the rectification of bugs. Regression testing's objective is to ensure that the software application's present functionality continues to perform as intended even after changes. Regression tests are typically a subset of the application's whole test suite and are created to cover the code's most important or vulnerable parts. Regression testing is important because it helps to ensure that changes to the code do not break existing functionality and that the software application is still stable and reliable.

On the other hand, smoke testing is a type of testing that is carried out to swiftly evaluate the fundamental functionality of a software programme. Smoke testing is typically carried out early in the development process, prior to the application being completely functioning, to ensure that the key features are operating as intended. Smoke tests are often a limited group of tests that focus on the most important aspects of the application and are intended to quickly spot any significant issues or flaws. Smoke testing is intended to give assurance that the application is stable enough to move forward with additional testing. Smoke testing is frequently referred to as "confidence testing" or "build verification testing."

In summary, regression testing is focused on verifying that changes to the software application have not introduced any new defects, while smoke testing is focused on quickly assessing the basic functionality of the application.

Q:Can you write a Python program to test the compatibility of a web application across different browsers using Selenium?

Python program that uses Selenium to test the compatibility of a web application across different browsers:

First we will import the necessary libraries and then defined some popular browsers and then will iterate throughthat list of browsers


from selenium import webdriver

url = "https://www.example.com"

browsers = ["chrome", "firefox", "edge", "safari"]

for browser in browsers:
if browser == "chrome":
driver_path = "path/to/chromedriver"
elif browser == "firefox":
driver_path = "path/to/geckodriver"
elif browser == "edge":
driver_path = "path/to/msedgedriver"
elif browser == "safari":
driver_path = "path/to/safaridriver"

driver = webdriver.Chrome(executable_path=driver_path)

# Load the web application in the webdriver
driver.get(url)

# Perform some compatibility tests on the web application
# For example, check that all elements are displayed correctly,
# that all links work, etc.

# Close the webdriver instance
driver.quit()

This code will open the web application in each of the specified browsers (Chrome, Firefox, Edge, and Safari) and perform some compatibility tests on it. You can customize the compatibility tests by adding your own code to the for loop.

Note that you will need to install the Selenium Python library and the appropriate webdrivers for each browser you want to test.