[Marc-André Moreau (mamoreau-devolutions)]

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Summary

Adds an optional, off-by-default Xcode extension on macOS 13+ (Settings > Extensions > Xcode) for browsing, downloading, installing, updating, and switching between side-by-side Xcode versions and Simulator runtimes — implemented natively in standalone C# (src/UniGetUI.Extensions.Xcode) with no external xcodes CLI or Xcodes.app dependency.

• macOS-only build & runtime gating (EnableXcodeExtension / UNIGETUI_XCODE_EXTENSION): Enabled by default when building on macOS or targeting osx-* RIDs, excluded from UniGetUI.Windows.slnx, and stripped from Windows and Linux builds (UniGetUI.Avalonia.csproj, Directory.Build.props, AppExtensions).
• Native Apple authentication & Keychain isolation (AppleAuth/):
  • Implements Apple SRP (s2k / s2k_fo), hashcash proof-of-work, and trusted-device / SMS 2FA sign-in in C# using source-generated JSON metadata (AppleAuthJsonContext).
  • Isolates authenticated requests through /usr/bin/curl -q over stdin (AppleCurlTransport) with an empty environment and RFC 6265 cookie handling so credentials, tokens, cookies, and URLs stay out of .NET HTTP diagnostics, process arguments, and environment variables.
  • Stores credentials and cookies under UniGetUI's own login Keychain service (com.devolutions.unigetui.xcode), never reading other tools' Keychain items. Uses unencrypted Keychain item attributes (kSecReturnAttributes + kSecAttrGeneric) for account status and external-change checks so startup and browsing never trigger a Keychain prompt; secrets are unlocked at most once when an Apple operation runs.
• Catalog, downloads, installation, and selection (Local/):
  • Combines the Xcode Releases feed (xcodereleases.com) with Apple's authenticated download catalog (listDownloads.action), including ADCDownloadAuth cookie authorization and automatic re-authentication if Apple's developer download session expires (resultCode: 1100).
  • Supports resumable .xip and .xip.aea archive downloads (XcodeArchiveDownloader) verified by SHA-1 / strong ETag validators and guarded by per-cache file locks.
  • Unpacks archives into staging (xip / aa), verifies build identity, Apple code-signing authority, and Gatekeeper (spctl), names side-by-side bundles (Xcode-26.6.app, build-disambiguated when needed), and runs privileged xcode-select / DevToolsSecurity / _developer group / license / first-launch setup (XcodeArchiveInstaller, XcodeSelector).
• Simulator runtimes: Lists installed and bundled runtimes (xcrun simctl) alongside Apple's downloadable catalog, supporting xcodebuild -downloadPlatform, runtime .dmg export, and direct public CDN .dmg downloads.
• Avalonia UI, Settings, and IPC:
  • Responsive master/detail Xcode page with flat and grouped version browsers, release/architecture/Installed only filters, active/installed header summary pill with click-to-focus, macOS compatibility warnings, scheduled update checks, and opt-in automatic updates.
  • Shared Apple ID card (XcodeAccountCard), dedicated settings page (XcodeSettings), and CLI/IPC support (unigetui app navigate xcode, documented in docs/CLI.md).
  • Includes src/UniGetUI.Extensions.Xcode/THIRD_PARTY_NOTICES.md attributing MIT-licensed XcodesOrg/xcodes, XcodesOrg/XcodesKit, XcodesOrg/XcodesApp, and blacktop/ipsw (test vectors).

Testing

• Xcode engine & auth suite (UniGetUI.Extensions.Xcode.Tests): 718 passed, 0 failed (including live macOS Keychain round-trip tests with UNIGETUI_KEYCHAIN_TESTS=1 and loopback TLS curl transport tests).
• UI & settings search suite (XcodeTests, SettingsSearchIndexTests): 375 passed, 0 failed (covering browser filtering/grouping, installed summary & focus flows, account/Keychain states, prompts, simulator runtimes, live-region safety, and responsive layout bounds).
• Formatting & translations:
  • dotnet format whitespace src --folder --verify-no-changes --verbosity minimal passed.
  • dotnet format style src/UniGetUI.Avalonia.slnx --no-restore --verify-no-changes --verbosity minimal passed.
  • pwsh ./scripts/translation/Verify-Translations.ps1 validated all 60 language files.
• Build, NativeAOT, and live verification: Verified osx-arm64 and osx-x64 NativeAOT publishes, linux-x64 / EnableXcodeExtension=false builds excluding UniGetUI.Extensions.Xcode, and interactive live testing in UniGetUI.app on macOS (Apple ID + SMS 2FA sign-in, deferred Keychain behavior, and authenticated Apple download handshake).

Known Limitations

• Accounts requiring hardware security keys (FIDO2/WebAuthn) or enterprise federated sign-in are not supported yet and fail closed with clear guidance.
• Selecting an Xcode bundle that is already the active xcode-select target verifies its Apple code signature before returning without re-running privileged directory ownership/ACL remediation.
• Terminal UI (unigetui tui) does not include an Xcode page.

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Closes: N/A
Relates to: N/A