End To End Testing vs Regression Testing: A Comprehensive Comparison

End-to-end testing is a type of software testing that checks the system as a whole from start to finish. Regression testing is software testing that checks for errors after changes have been made to the code. Both are important for the software development process. However, they are two different types of tests that serve different purposes.

End-to-end testing tests the system, whereas regression testing tests specific parts of the code. In general, end-to-end testing focuses on the system’s functionality, while regression testing prioritizes the system’s stability. Understanding the difference between end-to-end and regression testing is essential to know when to use each type of test. Keep reading to learn all you need about End-to-End testing vs. Regression testing!

End To End Testing – what is it?

End To End testing is a comprehensive approach covering all aspects of the software development cycle, from requirements gathering to final deployment. This type of testing is crucial because it ensures that the software meets all business and technical requirements and works as expected in all environments.

End To End testing can be divided into two main types:

• Functional testing and
• Non-functional testing
• Functional testing covers the software’s core functionality, while non-functional testing covers performance, security, and scalability aspects.

Both types of testing are essential to ensure that the software is ready for production. Functional testing often comes first to identify issues and address them before software deployment. Non-functional testing, the latter verifies that the software meets all performance goals. Non-functional testing test how the application interacts with hardware, network connections, external dependencies, databases, and other apps. E2E testing is often carried out soon after the systems and functional testing end.

Behaviorally-based frameworks are often utilized for E2E testing. You may use frameworks like Karate, Cypress, Katalon, Postman, Cucumber, Postman, and SoapUI. It should be noted that many API testing frameworks are utilized for end-to-end testing as API is often used to communicate programmatically with an app.

You should keep a few things in mind if you are thinking about implementing end-to-end testing in your software development process. First, end-to-end testing can be very time-consuming and resource-intensive. Next, you must ensure you have the resources necessary to carry out end-to-end testing properly.

Two methods of End-to-End testing

E2E testing is carried out in two different ways: Horizontal and Vertical. Although both can be beneficial, they are helpful in different ways, and it’s essential to recognize the variations.

Horizontal Testing:

The complete application across several platforms will be considered in a horizontal E2E test. It would be best if you had a well-defined methodology and established test environments to conduct this E2E testing. It is always better to pre-arrange setting these up.

Horizontal E2E testing fundamentally entails evaluating many systems simultaneously while confirming each workflow event from beginning to end.

Let’s examine an e-commerce application as an illustration. The tester may log into the user account and peruse the company’s items for a horizontal E2E test. After adding a few things to the cart, they would attempt to check out.

The developers and programmers must create practice tests from the user’s standpoint. The best part is that it will assist in resolving workflow difficulties before the program is put into production.

Vertical Testing:

A vertical E2E test dissects the application’s structure into many levels as opposed to a horizontal E2E test, which evaluates the program as a whole. Each layer must undergo individual testing before being subjected to a hierarchical analysis. Thus, a vertical E2E considers these layers rather than the application in terms of process.

Each layer is tested from the bottom up, including all UI, database cells, or API needs. Before going on to the next layer, they are stored apart from the other layers and examined separately.

Even though they are less frequent than horizontal E2E, they might be helpful in some situations. This is especially true when there are layers without a user interface or when there are safety-critical applications.

End-to-end testing has advantages over white-box and black-box testing.

White box testing closely resembles vertical end-to-end testing and looks at software or system’s internal architecture or inner workings.

Like horizontal end-to-end testing, black box testing focuses on functionality rather than investigating a system’s or program’s internal workings.

E2E testing: Is it Important?

End-to-end testing is widespread and essential since it:

• Generates more specific test cases than other testing techniques like unit and functional testing, which helps teams increase their test coverage and expands the test coverage regions throughout all the software systems and subsystems.
• Runs the test cases depending on the end user’s behavior to ensure the application functions correctly.
• Allows release teams to speed their time to market by automating essential user journeys.
• Decreases the time needed to test software, lowering the overall cost of producing and maintaining software.
• Aids in consistently and predictably detecting issues.
• Keeps an eye on everything and verifies the system flow.
• Detects subsystem problems, if any, and boosts the overall software system’s productivity.

Challenges in End-to-End testing

Although end-to-end testing is an excellent method for evaluating software, it can be challenging to accomplish. Here are a few typical issues that arise during E2E testing:

Slow execution and time consuming: End-to-End tests might be slow to execute since they cover every program component and run through the full software stack, especially compared to alternative testing methodologies that test isolated software components. It might take a while to complete testing that validates workflows through the user interface. Instead, businesses frequently utilize end-to-end testing for the user processes with the highest importance while using unit tests, snapshot tests, and integration tests more frequently for low priorities.

Complex/High maintenance: End-to-end testing is highly complicated since it involves simulating fundamental user interactions, the full software stack, and its dependencies. Therefore, extensive care and troubleshooting may be needed for E2E testing.

Difficulty in finding issues: Compared to a more detailed unit or integration test, when an E2E test fails, further investigation may be required to identify and resolve the problem.

Difficulty in environment testing: End to End testing might be more intricate and expansive in structure when compared to other testing methods. So separate scripts must be implemented to execute in various environments and browsers. This can’t be a viable method of obtaining results quickly.

What does Regression Testing entail?

Regression testing is a type of testing that is used to verify that changes to a software system have not introduced new bugs. This is usually done by re-running existing tests to see if they still pass the recent changes. Sometimes, further tests are also created to exercise the new changes specifically.

Regression testing is an integral part of the software development process, as it helps to ensure that new changes have not adversely affected the rest of the system. It is typically done early, often during development and release. Regression testing’s name derives from the term regress, which in software implies going back to a previous state or situation, which isn’t a desirable thing. Regression testing is also necessary when a new feature is included in the software program. Regression tests may also run when a performance or functional flaw is corrected.

Types of Regression Testing

Regression tests come in 7 different varieties. It always boils down to choosing the one that is ideal for you.

Corrective Regression Testing

When no relevant modifications have been made to the product’s specification, this regression testing is used. Corrective performance testing is feted for being straightforward and requiring little effort. Given that there haven’t been any significant modifications to the product specs, it reuses the current test cases (no need to change a testing scenario).

Retest-all Regression Testing

This is a problematic testing technique, as the name would imply, and all the system’s components must be tested afresh from scratch. This also entails testing every feature of a given product and reusing all test cases, even in areas or portions where no change has been made or created. Even if this kind of test is not recommended for a minor issue or change in the existing product, it is worth doing to know the system’s current state.

Selective Regression Testing

This regression test evaluates how the newly introduced code would affect the already installed application software. Selective regression testing uses a subset of test cases to examine the impacted code. This saves time and effort from creating a new test case and lowers retesting costs.

Progressive Regression Testing

This regression test performs admirably when minor modifications are made to the program requirements, and new test cases are created. The creation of new test cases occurs when the older ones become useless. This frequently occurs when the product specifications are altered, necessitating the creation of new test cases to account for the new needs.

Complete Regression Testing

This regression testing method is applied if significant changes appear in your test code. This is utilized primarily when there is a substantial modification to the software’s underlying code. Major companies use this testing method to cope with customer demands.

Partial Regression Testing

Your modules may have been in the pipeline for a while. When you merge those individual modules with a standard code mainline, partial testing is carried out, primarily using the existing test cases.

Unit Regression Testing

One of the most critical aspects of testing is unit regression testing. This test ensures that any resulting dependencies are blocked out throughout the test, even if it is primarily focused on the coding unit.

What makes regression testing important?

If you’re wondering why regression testing is vital, assume that a problem develops every time you update the code. Regression testing is used to preclude this. Because it enables developers to continuously improve programs without affecting the end user’s experience, it assures compatibility with current features and the functionality of new programs.

Standard Tools for E2E and Regression Testing

Many tools are available for end-to-end testing, but these handful of tools are practical and effective.

Avo Assure: With only a few button clicks, you can test whole business processes with Avo Assure, a 100% scriptless test automation solution.

testRigor: Using simple English language phrases, manual QA testers may build sophisticated end-to-end test automation with testRigor.

Selenium WebDriver: An open-source test automation framework called Selenium WebDriver enables you to create and execute tests for your web application in various settings.

Testsigma: Testing is done in plain English for online, native mobile apps, and APIs. With an AI-powered automated testing capability, it maintains release readiness.

What is the difference between E2E from Regression Testing?

Difference between E2E from Regression Testing is – Regression testing ensures that what worked yesterday still works, despite any modifications in SDLC where End-to-end testing involves testing a business process as a whole, From “end to end.”

Let’s have a look at End to End testing vs Regression testing key differences:

End to End Testing	Regression Testing
End to end testing is used to ensure that the software functions correctly from start to finish	Regression testing is used to ensure that software changes have not caused any new bugs.
End to end testing can be more time consuming as it tests the entire software system from start to finish	In general, regression testing is done more frequently than end to end testing.Which also consumes less time
End to end testing on the other hand is a much more comprehensive testing methodology that tests all aspects of the system from start to finish.	Regression testing is typically done after a code change to make sure that the code change did not break any existing functionality.
Workflow is the main focus in end to end testing	It concentrates on making sure that new developments don’t break already existing capabilities
Checks the efficiency of business operations by identifying problems with integrations or subsystem	Verifies the smooth operation of business processes by verifying that system updates do not affect the functionality of legacy code
Tests that replicate the end user experience in the real world are simulated in the production environment.	Tests are stimulated in the pre-production environment
Throughout the SDLC, tests are regularly executed	Tests are conducted only after a programming modification or release
There must be generated or new test cases	There are existing test cases, they will be repeated

The broader range of testing coverage is a significant and shared benefit of end-to-end testing and regression testing. The most important lesson for businesses considering using any of these testing approaches is that, despite the abundance of benefits, each one has a considerable amount of maintenance baggage to deal with.

Why Testsigma?

As discussed along with their advantages, disadvantages, and comparison in this blog, end-to-end regression testing with Testsigma saves time, avoids problems, and frees your employees to focus on developing applications. End-to-end testing may be a crucial component of comprehensive software testing, especially given its methodology. At the same time, the methods used for regression testing are primarily technical and at the component level. Due to these factors, businesses should select appropriate testing methods, provide sufficient resources, and leverage solutions like Testsigma to test and offer a reliable, high-quality user experience. Check out the “How to select the right Automated Regression Testing Tool?” for more information on how to think and choose a testing method for your business effectively.

Create a free account with Testsigma to see how automating your tests may help you find issues earlier and shorten release cycles!