Add ARJ and ARC decompression support

[Copilot]

Adds support for ARJ and ARC archive formats to RecursiveExtractor by leveraging the SharpCompress library's decompression capabilities introduced in version 0.42.0.

Changes Made

• SharpCompress Update: Updated package version from 0.40.0 to 0.44.3
• Archive Type Detection: Added ARJ and ARC archive types to the ArchiveFileType enum in MiniMagic.cs
• Magic Byte Detection:
  • ARJ: 0x60 0xEA at offset 0
  • ARC: 0x1A followed by compression method (0x01-0x09 or 0x7F for valid standard ARC)
• New Extractors: Created ArjExtractor.cs and ArcExtractor.cs using SharpCompress Reader API
• Extractor Registration: Registered ARJ and ARC extractors in Extractor.cs SetDefaultExtractors()
• Project Description: Updated to include ARJ and ARC formats
• Test Coverage: Added test archive files and tests for both formats in ExpectedNumFilesTests.cs and MiniMagicTests.cs

Resource Governor Handling

The ArcExtractor checks the resource governor after extraction using the actual decompressed content length (newFileEntry.Content.Length), following the same pattern as XzExtractor. This approach is necessary because SharpCompress's ARC implementation does not expose entry sizes upfront (throws NotImplementedException when accessing entry.Size).

Original prompt

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This section details on the original issue you should resolve

<issue_title>Add ARJ decompression, provided by SharpCompress</issue_title>
<issue_description>SharpCompress supports ARC and ARJ decompression starting from version 0.42.0. Would be great if RecursiveExtractor also supports these formats.</issue_description>

<agent_instructions>Please try to add support for these new formats recently added to sharpcompress. https://github.com/adamhathcock/sharpcompress. Make sure to bump the sharpcompress dependency to the latest version, and follow the existing patterns for implementing minimagic detection for the new archive types (checking for header/footer signature as appropriate for the new archive type) adding an archive file type to the enum and adding an extractor matching the existing interface patterns.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Add ARJ decompression, provided by SharpCompress #180

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[gfs]

@copilot revert the change to nuget.config

[Copilot]

@copilot revert the change to nuget.config

Reverted in 5693355.

[gfs]

/azp run

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[gfs]

@copilot Running the tests on this proposed change I see a test failure. Can you investigate and resolve? Be sure not to check in a modification to the nuget.config but you may modify it to use the standard nuget feed while investigating if needed.

[Copilot]

@copilot Running the tests on this proposed change I see a test failure. Can you investigate and resolve? Be sure not to check in a modification to the nuget.config but you may modify ...

Fixed in d8b877d. The test files TestData.arj and TestData.arc were not being copied to the output directory because they were missing CopyToOutputDirectory entries in the csproj file. Added the necessary entries to ensure the test data files are copied during build.

[gfs]

/azp run

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[gfs]

/azp run

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[Copilot]

Pull request overview

This PR adds support for ARJ and ARC archive formats to RecursiveExtractor by leveraging the SharpCompress library's decompression capabilities introduced in version 0.42.0.

Changes:

• Updated SharpCompress dependency from 0.40.0 to 0.44.3
• Added ARJ and ARC format detection via magic byte signatures and corresponding extractors
• Added test coverage for both new archive formats

Reviewed changes

Copilot reviewed 8 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
RecursiveExtractor.csproj	Updated SharpCompress package reference and project description to include new formats
MiniMagic.cs	Added ARJ and ARC enum values and magic byte detection logic
ArjExtractor.cs	New extractor implementation for ARJ archives using SharpCompress Reader API
ArcExtractor.cs	New extractor implementation for ARC archives with post-extraction resource governance
Extractor.cs	Registered ARJ and ARC extractors in SetDefaultExtractors()
RecursiveExtractor.Tests.csproj	Added test data files for ARJ and ARC formats
MiniMagicTests.cs	Added test cases for ARJ and ARC magic byte detection
ExpectedNumFilesTests.cs	Added extraction test cases for ARJ and ARC archives

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[gfs]

/azp run

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[gfs]

@copilot I'm seeing a test failure in the pipeline.

[Copilot]

@copilot I'm seeing a test failure in the pipeline.

I ran the tests locally and the ARJ/ARC specific tests (MiniMagic detection and ExpectedNumFiles) are passing. The test failures I observed (78 failures on net9.0) appear to be pre-existing issues not related to my changes: TestSanitizePathLinux, ExtractArchiveAndDisposeWhileEnumerating, EncryptedArchive tests, etc.

Could you share the specific test failure name from the Azure Pipeline? That would help me identify if there's an issue specific to my changes.