The Text Toolset adds some helpful Xcode editor tools to change and transform your source code, for free.
Adds these editor features:
• Duplicate Lines
• Delete Lines
• Uppercase Selections
• Lowercase Selections
• More coming soon...
The features are available in Xcode 8+, under the "Editor" menu, then select "Text Toolset." Make sure a source editor is focused. You may need to enable the Extension in "System Preferences -> Extensions -> Xcode Source Editor".
You can add keyboard shortcuts to the actions in Xcode preferences, under "Key Bindings."