Code Review

Summary

This PR enhances the secure context detection in crypto.ts by adding more robust checks before using the Web Crypto API. The changes improve reliability and compatibility across different browser environments.

Strengths

1. Improved Robustness: The addition of globalThis.isSecureContext check is the standard and most reliable way to detect secure contexts per the Web Platform specification.

2. Defense in Depth: Multiple layers of checks (secure context, crypto existence, crypto.subtle existence, digest function) provide excellent fallback behavior.

3. Better Error Handling: The try-catch wrapper prevents any unexpected errors from breaking the application, ensuring graceful degradation to crypto-js.

4. Clear Documentation: The updated comments explain the multi-check approach, making the code maintainable.

5. Null Safety: Explicit null checks for both crypto and crypto.subtle prevent potential runtime errors in edge cases.

Observations

Minor: Redundant globalThis Check (Line 30) - The typeof globalThis check is technically redundant in modern browsers and Node.js environments where globalThis is always defined. However, keeping it provides extra safety for very old environments, so this is acceptable.

Consideration: Test Coverage - The existing test suite doesn't explicitly test the new isSecureContext detection path. Consider adding a test case that mocks isSecureContext as false to verify the fallback behavior. However, this is not blocking as the existing tests cover the fallback behavior adequately.

Security Assessment

No security concerns identified. The changes actually improve security posture by:

• More reliably detecting when Web Crypto API can be safely used
• Preventing potential errors that could expose stack traces or debugging info
• Maintaining the existing SHA-256 hashing behavior (no cryptographic changes)

Performance Impact

Minimal performance impact. The additional checks are all synchronous and extremely fast. The try-catch wrapper has negligible overhead in the success path.

Code Quality

• Follows TypeScript strict mode conventions
• Consistent with project style
• Clear separation of concerns
• Good code comments

Pre-Merge Checklist

• No breaking changes
• Backward compatible (same API, better detection)
• No new dependencies
• Type-safe (TypeScript strict mode)
• Existing tests should pass
• Consider adding test for isSecureContext false path (optional)

Recommendation

Approve with optional test enhancement. The code is production-ready and improves reliability. The suggested test addition is a nice-to-have but not required for merge.