Extension to NSMutableAttributedString that creates a link.

NSMutableAttributedString+Hyperlink.swift

import Cocoa

extension NSMutableAttributedString {

    /// Makes the specified text a clickable hyperlink.
    func hyperlink(text: String, with url: URL, additionalAttributes: [NSAttributedStringKey: Any] = [:]) {
        var attributes = additionalAttributes
        attributes[.link] = url.absoluteString
        let range = (string as NSString).range(of: text)
        addAttributes(attributes, range: range)
    }
}