Add Comprehensive Test Coverage for chat_gpt_client.py

[brylie]

Objective

Implement thorough unit tests for the chat_gpt_client.py module to ensure robust functionality and maintain code quality. Aim for 80-90% test coverage.

Description

The chat_gpt_client.py module is responsible for interacting with the OpenAI API to generate chat responses. We need to create a comprehensive test suite that covers all critical code paths and edge cases.

Tasks

1. Set up a test file test_chat_gpt_client.py in the tests/ directory.
2. Implement unit tests for the following components:
   • get_chat_response_with_history function
   • Any helper functions or classes in the module
3. Use mocking to simulate OpenAI API responses and avoid actual API calls during testing.
4. Test various scenarios including:
   • Successful API responses
   • API errors and exception handling
   • Edge cases (e.g., empty messages, long message histories)
5. Verify that environment variables are correctly loaded and used.
6. Ensure proper error handling and logging are tested.
7. Use pytest fixtures for any repeated setup code.
8. Add parameterized tests for functions with multiple input scenarios.

Acceptance Criteria

• All tests pass successfully.
• Test coverage is between 80-90% as measured by a coverage tool.
• Edge cases and error scenarios are adequately covered.
• Mocking is used appropriately to avoid external API calls.
• Tests are well-documented and follow best practices for pytest.

Additional Notes

• Use pytest as the testing framework.
• Use pytest-cov to measure test coverage.
• Ensure tests are independent and can run in any order.