Test Discovery

Test discovery process in pytest goes as follows:

• It recursively looks for files in the given directories (use current working directory if no directory/file is given) and all their subdirectories that named with test_*.py or *_test.py.
• In each of the test files identified, it looks for functions/methods that start with test_ and classes that start with Test

We can always run tests in specific file by running pytest file or specific test in a test file pytest path/to/file::test_name