Code Coverage & Test Driven development

Testing the internal structures and working of the application

At unit testing level

Won't find missing functionality or requirements

• Control flow testing
• Data flow testing
• Branch testing
• Path testing
• Exception handling testing
• Thread safety testing
• Resource constraints testing

Penetration testing where the tester has some malicious intruder that has some knowledge and/or credentials for the system

• Deadlines are up
• Test cases complete and a certain number passed
• Test budget depleted
• Beta or alpha testing has ended
• Coverage of code and functionality requirements reach a specified point

• Function coverage
• Statement coverage - Line execution
• Decision coverage - Branches of control structures
• Condition coverage - Sub-expression evaluation (to T or F)
• Exception coverage - Try/Catch blocks

• Inverts traditional dev/test process
• No code is written unless a failing test case exists
• Refactor to eliminate duplication

• Write test cases
• Run test cases
• Fix/write code for failed test cases (will be all if no code exists)

• Refactor
• Test again

• Encourages simple designs
• Inspires confidence
• Ensures system is testable
• A test for every feature exists
• Encourage focus on interface over implementation
• Encourage focus on simpler tasks (passing a test)
• Faster bug discovery
• Improves code implementation time

• It ensures that tests really work
• The tests will catch errors

• GUI testing - Requires full functional testing
• Database interactions - Requires full functional testing
• Dependent on network configuration - Requires full functional testing
• No management buy-in

Tests are usually written by the developer, so code can have blind spots