Fix reportLink nil handling to prevent crashes when report functionality unavailable

[Copilot]

This PR addresses a crash issue where reportLink could be nil but was being force unwrapped, causing the app to crash when users attempted to report topics that don't have report functionality available.

Problem

The issue occurred in the feed detail parsing logic where:

1. When V2EX pages don't contain a report link (empty rawReportUrl), the reportLink property remained nil
2. Later, when users tried to report such topics, FeedDetailActions.swift would force unwrap state.model.reportLink!, causing a crash
3. The UI didn't account for cases where reporting wasn't available

Solution

Model Layer (FeedDetailInfo.swift):

• Added an else clause to initialize reportLink as an empty string when rawReportUrl is empty
• This ensures reportLink is never nil, preventing force unwrap crashes

Action Layer (FeedDetailActions.swift):

• Added a guard statement to safely check if reportLink exists and is not empty before proceeding
• Provides user feedback ("无法举报此主题") when report functionality is unavailable
• Gracefully handles the error case without crashing

UI Layer (FeedDetailPage.swift):

• Added canReport logic to disable the report button when reportLink is empty
• Improves user experience by preventing users from attempting impossible actions

Testing

Added a test case to verify that reportLink is properly initialized as an empty string rather than remaining nil.

This fix ensures the app handles V2EX topics that don't support reporting functionality without crashing, while maintaining full functionality for topics that do support reporting.

Fixes #4.

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[Copilot]

Pull Request Overview

This PR fixes a crash issue where reportLink could be nil but was being force unwrapped when users attempted to report topics that don't have report functionality available.

Key changes:

• Prevents nil reportLink by initializing it as empty string when no report URL is found
• Adds safety guards in report action to handle empty report links gracefully
• Updates UI to disable report button when reporting is unavailable

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
V2er/State/DataFlow/Model/FeedDetailInfo.swift	Ensures reportLink is initialized as empty string instead of remaining nil
V2er/State/DataFlow/Actions/FeedDetailActions.swift	Adds guard to safely check report link before proceeding with report action
V2er/View/FeedDetail/FeedDetailPage.swift	Adds logic to disable report button when report link is unavailable
V2erTests/V2erTests.swift	Adds test case to verify proper handling of empty report links

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[Copilot]

The removed line contains invalid syntax 13.5} which would cause compilation errors. This appears to be a formatting issue in the diff rather than intentional code.

[github-actions]

Code Coverage Report ❌

Current coverage: 0%