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The snapshot tests were actually a decent breadcrumb trail into what the code was supposed to do.
Start by running the test suite to see which snapshot tests fail, then analyze the diffs to understand the expected vs. actual output. Refactor the if/else chains and duplicated logic into cleaner, reusable functions while ensuring the snapshot tests pass, and update snapshots only if the changes are intentional and correct.
Pro tip: Before changing any code, use git to commit the current state so you can easily revert if needed. Also, treat snapshot tests as a safety net—if a snapshot fails, verify whether the change is a bug or an intended improvement before updating it.
Execute the test suite to see which snapshot tests fail. Note the specific test names and the diffs between expected and received output.
Examine the failing tests and trace the logic in the TypeScript code. Identify the if/else chains and duplicated logic that cause the discrepancies.
Extract duplicated logic into functions, replace if/else chains with clearer patterns (e.g., switch, polymorphism, or lookup tables), and ensure the behavior matches the expected snapshots.
After refactoring, run the tests again. If failures persist, debug further. If the new output is correct, update the snapshots intentionally.
Ensure all tests pass and the code is cleaner. Be prepared to explain your changes, trade-offs, and why the updated snapshots are correct.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
I added a few edge cases around the conditional branches but honestly I wasn't sure how thorough they wanted me to be.
Start by clarifying the scope of the existing snapshots and the component under test, then systematically identify untested edge cases, error paths, and boundary conditions. Prioritize additions based on risk and business impact, and propose a concrete plan to implement and validate the new tests.
Pro tip: Mention that snapshot tests often miss dynamic or conditional rendering paths; proposing targeted tests for those gaps shows you understand both testing strategy and real-world failure modes. Also, suggest using mutation testing to validate that new tests actually catch regressions.
Ask questions to understand what the snapshots currently cover, the component's responsibilities, and any known limitations. Review the snapshot files and related test code to map covered vs. uncovered scenarios.
Enumerate edge cases, error states, conditional branches, user interactions, and data variations not represented in snapshots. Consider boundary values, null/undefined inputs, and asynchronous behavior.
Rank the identified cases by likelihood of failure and potential impact on users or business logic. Focus on high-risk areas first, such as critical user flows or complex conditional logic.
Describe specific test cases to add, including the expected behavior and how they complement existing snapshots. Suggest using a mix of snapshot and assertion-based tests where appropriate.
Explain how you would run the new tests, ensure they fail before the fix (if applicable), and integrate them into CI. Mention monitoring test coverage and flakiness.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
First, identify the conditional logic and extract the conditions and outcomes into a data structure like a map or array of rules. Then, replace the if/else or switch with a lookup function that evaluates the rules in order. Finally, explain that this is the Strategy pattern (or Table-Driven Method) and justify why it improves maintainability, extensibility, and readability.
Pro tip: Mention that rule tables can be externalized to configuration files or databases, enabling business users to modify rules without code changes—a key advantage in enterprise systems like Salesforce.
Locate the conditional logic and list all condition-outcome pairs. Ensure you capture the order of evaluation and any default behavior.
Choose a data structure (e.g., array of objects, Map) to represent rules. Each rule should include a condition (predicate) and an action (result or function).
Write a function that iterates through the rules, evaluates each condition, and returns the corresponding action. Handle no-match cases with a default.
Replace the original conditional logic with the lookup. Write unit tests to ensure behavior is unchanged and edge cases are covered.
Articulate that this is the Strategy pattern (or Table-Driven Method). Discuss benefits like separation of concerns, ease of adding rules, and potential performance considerations.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.