Google Professional Cloud Developer Question 274
Select 3Google Cloud PlatformYou are developing a Google Cloud application and need to implement unit tests for your Cloud Functions to ensure they function correctly. Which of the following practices should you follow to create effective unit tests?
- A
Mock external dependencies such as Cloud Storage or Pub/Sub during testing.
- B
Write unit tests that depend on live Google Cloud resources to validate functionality.
- C
Use a testing framework like Mocha or Jest for organizing and running your tests.
- D
Ensure unit tests cover edge cases and unexpected inputs in your function logic.
- E
Deploy the Cloud Function to a staging environment before running unit tests.
Show answer and explanation
Correct answers: A, C, D
Explanation
The goal of unit testing is to test individual pieces of code, such as functions, in isolation to ensure they work as expected. Mocking external dependencies, leveraging a testing framework, and covering edge cases are essential practices for effective unit tests. Dependence on live resources or deploying to staging environments falls outside the scope of unit testing and aligns more with integration or end-to-end testing strategies.
- A. Correct.
Mocking external dependencies is a critical practice in unit testing to isolate the functionality of the code being tested. It avoids relying on live resources, making tests faster, more reliable, and easier to debug.
- B. Incorrect.
Unit tests should not depend on live Google Cloud resources, as this introduces external dependencies, which can lead to flakiness and slower execution. Such tests are considered integration tests, not unit tests.
- C. Correct.
Using a testing framework like Mocha or Jest helps organize test cases, structure assertions, and automate the testing process effectively, which is a best practice for unit testing.
- D. Correct.
Unit tests should cover edge cases and unexpected inputs to ensure the robustness of the function logic. This helps identify potential bugs and ensures the code handles various scenarios gracefully.
- E. Incorrect.
Deploying the Cloud Function to a staging environment is not part of unit testing. This step is more relevant to integration testing or end-to-end testing.