Java Debugging Round: Fix a Bug in a Real-World Open Source Repo (e.g., SnakeYAML)

Problem: Java Debugging (Open-Source Repo Troubleshooting) You are given a Java open-source repository (the interviewer will specify the exact repo/branch, e.g., SnakeYAML). The codebase contains one or more defects that cause either: existing unit/integration tests to fail, or a specific input to trigger an exception or incorrect output. Your task is to perform real-world debugging and deliver a fix within a limited time. What you need to do Clone/open the repository and follow the README to run the test suite successfully. Use the failing test output/stack trace to: identify the root cause (could be in parsing, serialization, type resolution, edge-case handling, error handling, etc.). Fix the bug and ensure: all existing tests pass; any additional test you add (if needed) covers the regression scenario. Explain to the interviewer: how you narrowed down the issue; what the root cause was; why the fix is correct; potential side effects. Input/Output (as provided in the debugging round) Input: the repository + a failing scenario (tests/stack trace/repro steps). Output: updated code (and possibly new tests) so that the full test suite passes. Constraints / Expectations Timebox: typically 45–90 minutes (as specified by the interviewer). Tools: IDE/search/docs usage depends on the interview rules. Large refactors are not required; prefer a small, safe, correct fix.