ros2-assignments/doc/tests/DatabaseManager.md

Database Manager Unit Tests

Unit tests for DatabaseManager are implemented in src/g2_2025_grade_calculator_pkg/test/DatabaseManager.test.cpp using Google Test and ROS2 test utilities. The tests are designed to work reliably whether a database connection is available or not, focusing on error handling and method behavior validation.

Test Cases

1. ConstructorTest

Description: Verifies that DatabaseManager can be created without crashing and proper initialization occurs.

• Test Action: Create DatabaseManager instance with ROS2 logger
• Expected Result: Instance created successfully without exceptions

2. ConnectionStatusTest

Description: Tests that the is_connected() method returns a valid boolean value.

• Test Action: Call is_connected() method
• Expected Result: Returns either true or false (no crashes or invalid states)

3. QueuePendingCombinationsTest

Description: Verifies retrieval of pending student-course combinations that need exam results.

• Test Action: Call queue_pending_combinations()
• Expected Result: Returns valid vector (empty if no database connection, populated if connected)

4. StoreExamResultTest

Description: Tests exam result storage with graceful handling of connection states.

• Test Action:
  • Student: "TestStudent"
  • Course: "TestCourse"
  • Grade: 85
• Expected Result: Returns false if no connection, true if connected and successful

5. EnrollStudentTest

Description: Tests student enrollment into courses.

• Test Action:
  • StudentCourse object with test data
• Expected Result: Returns false if no connection, true if connected and successful

6. GetFinalGradeTest

Description: Tests final grade retrieval for non-existent student-course combinations.

• Test Action:
  • Student: "NonExistentStudent"
  • Course: "NonExistentCourse"
• Expected Result: Returns -1 (no results found or no connection)

7. StoreFinalResultTest

Description: Tests storing calculated final course results.

• Test Action:
  • StudentCourse object
  • Exam count: 3
  • Final grade: 75
• Expected Result: Returns false if no connection, true if connected and successful