Generate and view a class diagram for Swift code in Xcode or from the Finder.

Use the hosting macOS application to configure the diagram visualization.

The Source Editor Extension (as well as the Action extension) makes use of SwiftPlantUML Swift package.

To generate a large diagram from a project with Swift files across folders then I recommend using SwiftPlantUML as a command-line tool.

• 📊 Create class diagram from Swift file
• 🔦 Create class diagram from selected Swift code

• 📊 Create class diagram from selected Swift file(s)

Homebrew

brew install swiftplantumlapp

Alternative

• Download latest SwiftPlantUML package from the Releases.
• Copy SwiftPlantUML to your Applications folder.

• Launch SwiftPlantUML.

  

• To use in Xcode: enable extension in System Preferences > Extensions > Xcode Source Editor > select SwiftPlantUML

  

• To use in Finder: enable extension in System Preferences > Extensions > Finder > select Open Swift Class Diagram

  

Optional:

Xcode Source Code Extension initialization might take up ~ 30 seconds on initial launch.

If the prompt does not appear within 60 seconds

then check for a crash report related to XPC service in Console app of your MacOS.

If you see such crash report related to fatal error: Loading sourcekitd.framework/Versions/A/sourcekitd failed please check the installation path of Xcode. If it's installed under /Applications/Xcode.app, please run:

sudo xcode-select -s /Applications/Xcode.app/Contents/Developer

If it's installed elsewhere, please replace the /Applications/Xcode.app path in the command above with the location where you've installed Xcode.

This Source Editor Extension makes use of XPC service to run the app sandboxed and use SwiftPlantUML (and its dependency SourceKitten). Source Editor Extensions using SourceKitten (either directly or indirectly) have to either run in a non-sandboxed app (and could not be distributed via the App Store) or use XPC service to outsource the use of SourceKitten to a different process.

These awesome blog posts helped me to dive into Xcode Source Editor Extensions and XPC services

• https://www.vadimbulavin.com/xcode-source-editor-extension-tutorial/
• https://nshipster.com/xcode-source-extensions/
• https://ilya.puchka.me/xcode-source-editor-extension-superpowered-with-sourcekitten/
• https://www.objc.io/issues/14-mac/xpc/