Understanding happy path testing (And why you need to think beyond it)

Happy path testing is a software testing technique that examines the most direct path a user can take with your software and the desired outcome of that path. Typically, happy path testing is one of the first testing techniques your team performs and is a great way to gain a better understanding of the intended experience with your software.

While some people use happy path interchangeably with golden path testing, the two actually serve different functions for your testing team.

Happy path testing looks at individual workflows and user journeys. It helps your team individually test intended use cases for every experience within your product.

Golden path testing takes a more holistic view of your software and helps your team examine how users get the most value from their experience interacting with your software.

To better understand happy path testing and how it functions as a part of the software testing lifecycle and the software development lifecycle (SDLC) as a whole, it’s essential to understand what goals to set for happy path testing.

Happy path testing validates expected outcomes

Happy path testing looks at expected outcomes and optimal user flows — the primary goal is to validate software functionality in terms of baseline performance. Performing this type of testing helps you solidify core functionality for a new piece of software and confirm that it meets basic functionality requirements.

Happy path testing also helps you see whether or not your new feature delivers the desired value for users. It is performed by internal software testers and gives your team a way to verify that the software can handle expected user interactions without bugs or obvious usability flaws.

You perform happy path testing at the beginning of the testing process, just after your development team has deployed new or updated code to your testing environment. The reason for this early testing is so that your team can verify that your software experience matches business requirements and intended use cases. 

An example of a happy path scenario

Let’s say you’re an email marketing service provider, and you’ve just built a new bulk email import functionality for your application. An effective happy path test would be to work through the intended user flow of importing a bulk list of emails using this tool. For example:

1. A user opens the application and selects the “Email Import” option
2. The user clicks the option to “Bulk Upload a List” and selects a file
3. The system asks what mailing list the user wants to add emails to
4. The user clicks to initiate the import and is notified of the time it will take to process
5. The system imports the emails correctly and notifies the user it is complete
6. The user checks the emails and confirms they’ve been added to the correct list

In this example, your internal testing team would work through this process to ensure that each step functions as intended and all alerting messages trigger correctly.

Unhappy path testing looks at pain points and friction

The opposite of happy path testing is unhappy path testing, which is also known as sad path or expectation path testing. The purpose is to test for user flows that cause friction or have known pain points for users. Unhappy path testing aims to understand how your software reacts to input errors and expectations.

By focusing on the pain points and friction a user might encounter when using your software, your testing team can establish a user experience that accounts for these issues while still providing support. This is an important aspect of quality assurance, as you can’t count on always having ideal conditions or predictable users. 

It’s a good idea to perform unhappy path testing at the same time as happy path testing, which is after you’ve deployed new or updated code to your testing environment. Using both testing techniques in tandem ensures that your team can cover all expected and unexpected conditions before moving on to different user acceptance testing methods.

An example of an unhappy path scenario

Going back to the email marketing example from before, let’s say you want to test how your system notifies users that the list they’re trying to upload is not in the correct format. In that case, your unhappy path test would look something like this:

1. A user opens the application and selects the “Email Import” option
2. The user clicks the option to “Bulk Upload a List” and selects a file
3. The system parses that file and sees that it is a PDF instead of a CSV or XLS file
4. The system notifies the user via a popup that the file type is incorrect and provides information on the accepted file types
5. The system cancels the upload and notifies the user

Your internal testing team would walk through this process step by step to ensure that the system parses the files correctly, notifies the users of the invalid formatting or information, and lets the users know that the file has not been uploaded to their account.

Happy path testing versus positive testing 

Happy path testing and positive testing are similar, but there are significant differences to consider between the two techniques. Technically, happy path testing is a subset of positive testing that looks at the most common user flows or experiences someone might encounter when interacting with your software. Positive testing is a testing technique that ensures that any new or updated piece of software works as expected and provides the correct outputs.

For example, a happy path test might look at the checkout process from start to finish — examining how the user selects a product, adds it to the cart, and checks out. Positive testing might look at the search functionality on your product page — examining whether a search for relevant keywords displays the correct items or if the dropdown menus contain the right options.

Unhappy path testing versus negative testing

Similarly, unhappy path testing is a subset of negative testing. Where happy path testing looks at how the software reacts to expected inputs and actions from users, negative testing, like unhappy path testing, looks at how your software performs when a user inputs invalid data or encounters an error.

Negative testing is a great technique for testing software resilience and compliance. Let’s imagine that a user goes through the product checkout user flow and enters an invalid mailing address under their billing information. Your testing team would use negative testing to ensure that, when those invalid inputs occur, the software reacts as expected and serves the correct error message. You can also check to ensure that the message explains how the user can resolve the issue and proceed with their request.

Happy path and unhappy path testing work best together

As both happy and unhappy path testing is performed by internal testers on your team, they’re a great way to validate baseline software functionality before more robust and intensive tests occur. Your team can use these testing methodologies to ensure that the most common and expected user inputs function correctly and ensure that invalid inputs (such as incorrect file formats) result in the proper error message.