Fix crash when tapping Hacker News comment permalinks

[weiran]

• Replace fragile string manipulation with robust URLComponents parsing in CommentTableViewCell
• Add defensive programming to HtmlParser to handle comment permalink HTML structure
• Prevents crash on line 45 of HtmlParser when parsing comment pages
• Fixes issue Crash when tapping a comment permalink #294: app now gracefully handles comment permalinks

🤖 Generated with Claude Code

Resolves #294

Summary by CodeRabbit

• Bug Fixes
  • Improved handling of URL interactions to safely extract post IDs from links, reducing the risk of errors when opening internal links.
  • Enhanced error handling when parsing titles from HTML, preventing potential crashes if expected elements are missing.

[coderabbitai]

Walkthrough

The changes update URL query parameter extraction in comment cell link handling to use URLComponents for safety and correctness, and improve error handling in HTML parsing by replacing a forced unwrap with guarded optional binding and descriptive error reporting.

Changes

Cohort / File(s)	Change Summary
Comment Cell URL Handling App/Comments/CommentTableViewCell.swift	Refactored URL parsing logic to use URLComponents for extracting the "id" parameter, replacing substring search. Logic for handling internal and external links remains unchanged.
HTML Parser Error Handling Shared Frameworks/HackersKit/HtmlParser.swift	Replaced forced unwrap of anchor element with guarded optional binding. Now throws a descriptive exception if the element is missing, preventing runtime crashes.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~7 minutes

Poem

In codey burrows deep and neat,
The rabbit hops with nimble feet.
URLs parsed with safer care,
And HTML with errors rare.
No more crashes, no more dread—
Just carrot code and bugs unfed! 🥕

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📜 Recent review details

Configuration used: CodeRabbit UI
Review profile: CHILL
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📥 Commits

Reviewing files that changed from the base of the PR and between 1082dc1 and c80de71.

📒 Files selected for processing (2)

• App/Comments/CommentTableViewCell.swift (1 hunks)
• Shared Frameworks/HackersKit/HtmlParser.swift (1 hunks)

🔇 Additional comments (2)

Shared Frameworks/HackersKit/HtmlParser.swift (1)

45-48: Excellent crash prevention improvement!

The replacement of the forced unwrap (first()!) with safe optional binding using guard let is precisely the type of defensive programming needed to prevent the crash mentioned in issue #294. The descriptive error message will aid in debugging if this condition occurs.

App/Comments/CommentTableViewCell.swift (1)

104-106: Robust URL parsing implementation!

The replacement of fragile string manipulation with URLComponents parsing is a significant improvement. This approach safely handles malformed URLs and properly extracts query parameters, directly addressing the crash issue with comment permalinks mentioned in the PR objectives.

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