NSTextView subclass that displays and opens hyperlinks.

HyperlinkTextView.swift

// You don't necessarily need this subclass if your NSTextView is selectable.
// If it isn't though, this allows you to have an uneditable, unselectable label where links work as expected.

import AppKit

class HyperlinkTextView: NSTextView {

    override func mouseDown(with event: NSEvent) {
        super.mouseDown(with: event)
        openClickedHyperlink(with: event)
    }

    override func resetCursorRects() {
        super.resetCursorRects()
        addHyperlinkCursorRects()
    }

    /// Displays a hand cursor when a link is hovered over.
    private func addHyperlinkCursorRects() {
        guard let layoutManager = layoutManager, let textContainer = textContainer else {
            return
        }

        let attributedStringValue = attributedString()
        let range = NSRange(location: 0, length: attributedStringValue.length)

        attributedStringValue.enumerateAttribute(.link, in: range) { value, range, _ in
            guard value != nil else {
                return
            }

            let rect = layoutManager.boundingRect(forGlyphRange: range, in: textContainer)
            addCursorRect(rect, cursor: .pointingHand)
        }
    }

    /// Opens links when clicked.
    private func openClickedHyperlink(with event: NSEvent) {
        let attributedStringValue = attributedString()
        let point = convert(event.locationInWindow, from: nil)
        let characterIndex = characterIndexForInsertion(at: point)

        guard characterIndex < attributedStringValue.length else {
            return
        }

        let attributes = attributedStringValue.attributes(at: characterIndex, effectiveRange: nil)

        guard let urlString = attributes[.link] as? String, let url = URL(string: urlString) else {
            return
        }

        NSWorkspace.shared.open(url)
    }
}