1. Unit Testing
Brian Hu

2. Why Test
• Catch errors
• Help you write code
• Speed up your development
• Cover configurations
• Cover new co-workers

3. What is a unit test
• Tests ONE thing
• Single “unit” of functionality
• Small, fast, ISOLATED

4. Unit Tests don’t cover
• Performance
• UI interaction
• Whole system integration

5. Guidelines
• Testing should be automated and non-interactive
• Let your code JUST pass the test
• Remember to test boundary cases, but also remember that it’s
impossible to test every case
• Provide a random generator when it’s possible
• Keep testing at unit level
• Act as 3rd party class consumer
• Passed tests don’t promise the correctness of code

6. XCTest

7. Tutorial Project
http://is.gd/nDMTWU

8. Instruction
• We have 4 tests in this project: testValidateEmail,
testSubmit, testIsEmpty, testValidatePassword
• I’ll do the “testValidateEmail” step by step for you.
• I have written the tests of “testIsEmpty” and
“testSubmit” for you. Please implement the logic
by yourself.
• Please write the test and implement the logic for
the last test by yourself.

9. API you may need
#if DEBUG
[NSException raise:@“Invalid Email Exception”
format:@"email is invalid”];
#endif

10. Password requirement
• length between 6~12
• has at least 1 uppercase letter and 1 lowercase
letter