Test Class for Apex Class in Salesforce – Detailed Guide for Newbies

In the Salesforce empire, the importance of Apex Classes is like a strong base of a grand building. They help you create and run special, personalized rules and automation for your business.

However, operating it requires a good knowledge. Therefore, we’ve created this detailed guide in a way that's easy to grasp to provide you with a deep understanding of the test class for Apex class in Salesforce.

Whether you're a newcomer on your Salesforce journey or seeking to refine your skills, this resource is your dependable companion. Besides, this blog will help show each step and give you expert advice to become good at this essential part of Salesforce development. So, let’s begin!

What is Test Class for Apex Class in Salesforce?

A Test Class for Apex Class in Salesforce is created for testing and verifying the functionality of a specific Apex class (or sometimes an Apex trigger) on the Force.com platform. These tests, known as Apex unit tests, play an essential role in maintaining the quality of your Apex code and meeting the requirements for deploying it.

The primary purpose of these test classes is to simulate real-world scenarios and conditions in a controlled environment, verifying that your Apex code performs as expected. This verification process is essential to prevent errors and issues when deploying your code to production.

Create your Apex Test Class

In the above example, we’ve described a simple class known as “AccountUpdateClass.“ This class has a single method to update the name of an “Account record.” After that, we defined an “Apex test class” known as “TestAccountUpdateClass.“ It possesses a single method for testing named “testUpdateAccount().”

Now, in the test method, here's what we do:

• Firstly, we set/create a test Account record.

• We then use the "updateAccount()" method from the "AccountUpdateClass" on this test Account.

• Lastly, we double-check if the Account's name has changed as we want it. We check this by looking up the Account record and using the "System.assertEquals()" method to ensure everything matches as expected.

Following the above example as a guide, you can make your simple class and the matching Apex test class, allowing you to begin testing your personalized code in Salesforce.

Top 6 Best Practices With Examples for Creating Test Class for Apex Class in Salesforce

The following best practices will help you meet your goal, streamline your testing process, and enhance the overall quality of your Salesforce applications.

1. Employ System.assert() Statements

The “System.assert()” method is crucial to verify whether the particular condition of your Apex code is true or false. This testing tool lets you examine that your code behaves as intended. For instance, you can employ “System.assert()” to confirm that a variable isn’t null or that a method yields the correct value.

Example

2. Use Test.startTest() and Test.stopTest()

The “Test.startTest()” and “Test.stopTest()” methods are employed to describe a block/portion of code that should executed within a distinct test context. It becomes helpful when your code needs to test governor limits, like limitations on the number of records that it can handle in one go. These methods ensure that your tests stay within the boundaries and your code operates correctly in real-world scenarios or a production environment.

Example

3. Utilize Test Data Factory Methods

While testing software or systems, creating test data is a critical step. This test data should accurately reflect the actual data used in the production environment. Therefore, you should use the “Test Data Factory” method to ensure efficiency and accuracy in your process.

Importantly, keep these data creation methods separate from the actual tests you perform. It's like having a particular kitchen area to prepare your ingredients before starting cooking. This separation helps keep your tests organized and makes it easier to reuse the same data for different tests.

Example

4. Use @testSetup

The @testSetup annotation is a special instruction used in Salesforce Apex testing. This method will run automatically before any test methods in the test class.

The primary purpose of “@testSetup” is to prepare and set up test data that you can use by multiple test methods. Additionally, one of the key benefits of using @testSetup is that it ensures your test data is created only once, regardless of how many test methods you have in the class. It can significantly improve the efficiency and speed of your tests.

Without it, you might conclude recreating the same test data multiple times, which can slow down your tests.

Example

5. Use @isTest(SeeAllData=false)

The @isTest annotation is a tool used in Salesforce to define a method or class as a test class or test method. You can use the “SeeAllData” parameter to determine whether the test class or test method can access all the Salesforce organization’s data or only access the specifically created data by the test(itself).

Besides, by setting “SeeAllData” to false, your tests become isolated from the existing data in the organization. This isolation makes your tests more reliable because they won't be influenced by data that may change or be unrelated to the specific test scenario. In other words, your tests are more controlled and predictable.

Example

6. Employ the @testVisible Annotation

The “@testVisible” annotation allows test classes to see and use an Apex class or method, even if it’s originally marked as "private," which means it's usually hidden from test classes.

This annotation comes in handy when you want to test methods or classes that are usually off-limits to test classes. By using @testVisible, you ensure that your test classes can access the hidden methods or classes when needed for testing purposes.

Example

Sum Up

Apex Test classes are a crucial part of Salesforce development. These classes help you ensure that your code works correctly and your business logic is solid.

Besides, you can use some best practices, including using System.assert() to check your code, using Test.startTest() and Test.stopTest() for specific sections of your tests, creating Test Data Factory Methods to make your test data, marking important methods with @testSetup, and setting @isTest(SeeAllData=false) to control data access.

By applying these practices in your code, you can be confident that your code works as intended, catches problems early, and saves time and effort in the long run.

You might also like: How to Write Test Class in Salesforce.