What are the best practices while writing Test Classes in Salesforce?

Hi Ratnesh,

Some of the best practices for writing test classes are:-

1-Try not just covering 75% of the code, but as much coverage as possible

2-If possible Don’t use seeAllData=true, Create your Own Test Data.

3-Always use @testSetup method dedicated to create test records for that class. This is newly added annotation and very powerful. Any record created in this method will be available to all test methods of that class.

4-Use Test.startTest() to reset Governor limits in Test methods

5-Use Test.isRunningTest() in your code to identify that context of class is Test or not.