Warn on duplicate update targets and avoid quadratic entry matching

[ChanTsune]

Summary

Resolves two review leftovers from #3007 in update's entry matching: a warning is now emitted when different source paths collapse onto the same archive entry name (identical-path duplicates from overlapping sources stay silent), and the matching loop is rewritten from O(N×M) shift_remove to O(1) lookups while preserving insertion order.

Notes

• Archive output is unchanged; the only user-visible delta is the new stderr warning, which also applies to the shared compat bsdtar -u path.

Refs #1547

Summary by CodeRabbit

• Bug Fixes

  • Improved update behavior when multiple source paths map to the same archive entry, including idempotent handling of duplicate source arguments.
  • Added clearer stderr warnings when different source spellings resolve to the same target, while preserving the first mapping.
  • Prevented already-matched archive entries from being re-added during updates, avoiding inconsistencies.

• Tests

  • Added CLI integration coverage for duplicate and overlapping update sources, including warning assertions.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 07a7ad8d-1b53-4c5e-94c5-cbd1605d24c0

📥 Commits

Reviewing files that changed from the base of the PR and between 4725f66 and 573741b.

📒 Files selected for processing (3)

• cli/src/command/update.rs
• cli/tests/cli/update.rs
• cli/tests/cli/update/duplicate_targets.rs

✅ Files skipped from review due to trivial changes (1)

• cli/tests/cli/update.rs

🚧 Files skipped from review as they are similar to previous changes (1)

• cli/src/command/update.rs

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📝 Walkthrough

Walkthrough

The update matching in run_update_archive now consumes archive-entry matches from an IndexMap value slot, warns on colliding source spellings, and only appends entries that were never consumed. New CLI tests cover duplicate and non-duplicate source combinations.

Changes

Duplicate target handling

Layer / File(s)	Summary
Mapping logic and remaining-entries loop cli/src/command/update.rs	Matching logic now uses Option-wrapped map values consumed via get_mut/take instead of shift_remove, warns when multiple sources map to the same entry, and the remaining-entries loop iterates only unconsumed values via into_values().flatten().
Integration tests for duplicate targets cli/tests/cli/update.rs, cli/tests/cli/update/duplicate_targets.rs	Registers a new duplicate_targets test module with four tests covering duplicate sources, overlapping directory/file arguments, single-source updates, and colliding path spellings that trigger the warning.

Estimated code review effort: 2 (Simple) | ~15 minutes

Sequence Diagram(s)

sequenceDiagram
  participant CLI
  participant run_update_archive
  participant target_files_mapping
  participant Archive

  CLI->>run_update_archive: invoke update with source paths
  run_update_archive->>target_files_mapping: build entry_name -> Option((idx, item))
  target_files_mapping-->>run_update_archive: duplicate entry name detected
  run_update_archive->>run_update_archive: warn about colliding source spellings
  loop for each archive entry
    run_update_archive->>target_files_mapping: get_mut(entry_name).and_then(Option::take)
    target_files_mapping-->>run_update_archive: consumed item or None
    run_update_archive->>Archive: apply matched update
  end
  run_update_archive->>target_files_mapping: into_values().flatten()
  target_files_mapping-->>run_update_archive: remaining unconsumed entries
  run_update_archive->>Archive: append remaining entries

Loading

Possibly related PRs

• ChanTsune/Portable-Network-Archive#2523: This earlier update-related PR also changes cli/src/command/update.rs around the same archive-entry update flow and type usage.
• ChanTsune/Portable-Network-Archive#2984: Both PRs modify cli/src/command/update.rs’s run_update_archive flow and update-entry selection behavior.
• ChanTsune/Portable-Network-Archive#3014: Both PRs touch run_update_archive logic that decides how update inputs are reused or appended.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the two main changes: duplicate-target warnings and faster entry matching.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cli/update/entry-matching-improvements

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[gemini-code-assist]

Code Review

This pull request optimizes the archive update process by changing the target files mapping from using shift_remove (which is O(n)) to using Option::take with get_mut (which is O(1)), avoiding quadratic complexity. It also introduces warnings when distinct source paths map to the same archive entry while remaining idempotent (and silent) when the exact same path is specified multiple times. Additionally, comprehensive integration tests have been added to verify these behaviors. There are no review comments to address, and I have no further feedback to provide.

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