Code Folding

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample/Views/ContentView.swift

@@ -26,12 +26,14 @@ struct ContentView: View {
     @State private var font: NSFont = NSFont.monospacedSystemFont(ofSize: 12, weight: .medium)
     @AppStorage("wrapLines") private var wrapLines: Bool = true
     @AppStorage("systemCursor") private var useSystemCursor: Bool = false
+
     @State private var indentOption: IndentOption = .spaces(count: 4)
     @AppStorage("reformatAtColumn") private var reformatAtColumn: Int = 80
 
     @AppStorage("showGutter") private var showGutter: Bool = true
     @AppStorage("showMinimap") private var showMinimap: Bool = true
     @AppStorage("showReformattingGuide") private var showReformattingGuide: Bool = false
+    @AppStorage("showFoldingRibbon") private var showFoldingRibbon: Bool = true
     @State private var invisibleCharactersConfig: InvisibleCharactersConfiguration = .empty
     @State private var warningCharacters: Set<UInt16> = []
 
@@ -86,6 +88,7 @@ struct ContentView: View {
                     indentOption: $indentOption,
                     reformatAtColumn: $reformatAtColumn,
                     showReformattingGuide: $showReformattingGuide,
+                    showFoldingRibbon: $showFoldingRibbon
                     invisibles: $invisibleCharactersConfig,
                     warningCharacters: $warningCharacters
                 )

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample/Views/StatusBar.swift

@@ -27,6 +27,7 @@ struct StatusBar: View {
     @Binding var indentOption: IndentOption
     @Binding var reformatAtColumn: Int
     @Binding var showReformattingGuide: Bool
+    @Binding var showFoldingRibbon: Bool
     @Binding var invisibles: InvisibleCharactersConfiguration
     @Binding var warningCharacters: Set<UInt16>
 
@@ -47,6 +48,7 @@ struct StatusBar: View {
                 .onChange(of: reformatAtColumn) { _, newValue in
                     reformatAtColumn = max(1, min(200, newValue))
                 }
+                Toggle("Show Folding Ribbon", isOn: $showFoldingRibbon)
                 if #available(macOS 14, *) {
                     Toggle("Use System Cursor", isOn: $useSystemCursor)
                 } else {

Package.swift

@@ -17,7 +17,7 @@ let package = Package(
         // A fast, efficient, text view for code.
         .package(
             url: "https://github.com/CodeEditApp/CodeEditTextView.git",
-            from: "0.11.3"
+            from: "0.11.4"
         ),
         // tree-sitter languages
         .package(

Sources/CodeEditSourceEditor/Controller/TextViewController+GutterViewDelegate.swift

@@ -8,8 +8,7 @@
 import Foundation
 
 extension TextViewController: GutterViewDelegate {
-    public func gutterViewWidthDidUpdate(newWidth: CGFloat) {
-        gutterView?.frame.size.width = newWidth
-        textView?.textInsets = textViewInsets
+    public func gutterViewWidthDidUpdate() {
+        updateTextInsets()
     }
 }

Sources/CodeEditSourceEditor/Controller/TextViewController+LoadView.swift → Sources/CodeEditSourceEditor/Controller/TextViewController+Lifecycle.swift

@@ -9,6 +9,23 @@ import CodeEditTextView
 import AppKit
 
 extension TextViewController {
+    override public func viewWillAppear() {
+        super.viewWillAppear()
+        // The calculation this causes cannot be done until the view knows it's final position
+        updateTextInsets()
+        minimapView.layout()
+    }
+
+    override public func viewDidAppear() {
+        super.viewDidAppear()
+        textCoordinators.forEach { $0.val?.controllerDidAppear(controller: self) }
+    }
+
+    override public func viewDidDisappear() {
+        super.viewDidDisappear()
+        textCoordinators.forEach { $0.val?.controllerDidDisappear(controller: self) }
+    }
+
     override public func loadView() {
         super.loadView()
 
@@ -17,7 +34,7 @@ extension TextViewController {
 
         gutterView = GutterView(
             configuration: configuration,
-            textView: textView,
+            controller: self,
             delegate: self
         )
         gutterView.updateWidthIfNeeded()
@@ -129,6 +146,7 @@ extension TextViewController {
             self.gutterView.frame.size.height = self.textView.frame.height + 10
             self.gutterView.frame.origin.y = self.textView.frame.origin.y - self.scrollView.contentInsets.top
             self.gutterView.needsDisplay = true
+            self.gutterView.foldingRibbon.needsDisplay = true
             self.reformattingGuideView?.updatePosition(in: self)
             self.scrollView.needsLayout = true
         }

Sources/CodeEditSourceEditor/Controller/TextViewController+StyleViews.swift

@@ -13,7 +13,7 @@ extension TextViewController {
         // swiftlint:disable:next force_cast
         let paragraph = NSParagraphStyle.default.mutableCopy() as! NSMutableParagraphStyle
         paragraph.tabStops.removeAll()
-        paragraph.defaultTabInterval = CGFloat(tabWidth) * fontCharWidth
+        paragraph.defaultTabInterval = CGFloat(tabWidth) * font.charWidth
         return paragraph
     }
 

Sources/CodeEditSourceEditor/Controller/TextViewController+TextFormation.swift

@@ -11,23 +11,6 @@ import TextFormation
 import TextStory
 
 extension TextViewController {
-
-    internal enum BracketPairs {
-        static let allValues: [(String, String)] = [
-            ("{", "}"),
-            ("[", "]"),
-            ("(", ")"),
-            ("\"", "\""),
-            ("'", "'")
-        ]
-
-        static let emphasisValues: [(String, String)] = [
-            ("{", "}"),
-            ("[", "]"),
-            ("(", ")")
-        ]
-    }
-
     // MARK: - Filter Configuration
 
     /// Initializes any filters for text editing.

Sources/CodeEditSourceEditor/Controller/TextViewController.swift

@@ -48,6 +48,9 @@ public class TextViewController: NSViewController {
     var localEvenMonitor: Any?
     var isPostingCursorNotification: Bool = false
 
+    /// A default `NSParagraphStyle` with a set `lineHeight`
+    lazy var paragraphStyle: NSMutableParagraphStyle = generateParagraphStyle()
+
     // MARK: - Public Variables
 
     /// Passthrough value for the `textView`s string
@@ -170,23 +173,23 @@ public class TextViewController: NSViewController {
     /// This will be `nil` if another highlighter provider is passed to the source editor.
     internal(set) public var treeSitterClient: TreeSitterClient?
 
-    package var fontCharWidth: CGFloat { (" " as NSString).size(withAttributes: [.font: font]).width }
+    var foldProvider: LineFoldProvider
 
     /// Filters used when applying edits..
-    internal var textFilters: [TextFormation.Filter] = []
+    var textFilters: [TextFormation.Filter] = []
 
-    internal var cancellables = Set<AnyCancellable>()
+    var cancellables = Set<AnyCancellable>()
 
     /// The trailing inset for the editor. Grows when line wrapping is disabled or when the minimap is shown.
-    package var textViewTrailingInset: CGFloat {
+    var textViewTrailingInset: CGFloat {
         // See https://github.com/CodeEditApp/CodeEditTextView/issues/66
         // wrapLines ? 1 : 48
         (minimapView?.isHidden ?? false) ? 0 : (minimapView?.frame.width ?? 0.0)
     }
 
-    package var textViewInsets: HorizontalEdgeInsets {
+    var textViewInsets: HorizontalEdgeInsets {
         HorizontalEdgeInsets(
-            left: showGutter ? gutterView.gutterWidth : 0.0,
+            left: showGutter ? gutterView.frame.width : 0.0,
             right: textViewTrailingInset
         )
     }
@@ -199,13 +202,15 @@ public class TextViewController: NSViewController {
         configuration: SourceEditorConfiguration,
         cursorPositions: [CursorPosition],
         highlightProviders: [HighlightProviding] = [TreeSitterClient()],
+        foldProvider: LineFoldProvider? = nil,
         undoManager: CEUndoManager? = nil,
         coordinators: [TextViewCoordinator] = []
     ) {
         self.language = language
         self.configuration = configuration
         self.cursorPositions = cursorPositions
         self.highlightProviders = highlightProviders
+        self.foldProvider = foldProvider ?? LineIndentationFoldProvider()
         self._undoManager = undoManager
         self.invisibleCharactersCoordinator = InvisibleCharactersCoordinator(configuration: configuration)
 
@@ -249,28 +254,6 @@ public class TextViewController: NSViewController {
         self.gutterView.setNeedsDisplay(self.gutterView.frame)
     }
 
-    // MARK: Paragraph Style
-
-    /// A default `NSParagraphStyle` with a set `lineHeight`
-    package lazy var paragraphStyle: NSMutableParagraphStyle = generateParagraphStyle()
-
-    override public func viewWillAppear() {
-        super.viewWillAppear()
-        // The calculation this causes cannot be done until the view knows it's final position
-        updateTextInsets()
-        minimapView.layout()
-    }
-
-    override public func viewDidAppear() {
-        super.viewDidAppear()
-        textCoordinators.forEach { $0.val?.controllerDidAppear(controller: self) }
-    }
-
-    override public func viewDidDisappear() {
-        super.viewDidDisappear()
-        textCoordinators.forEach { $0.val?.controllerDidDisappear(controller: self) }
-    }
-
     deinit {
         if let highlighter {
             textView.removeStorageDelegate(highlighter)

Sources/CodeEditSourceEditor/Enums/BracketPairs.swift

@@ -0,0 +1,29 @@
+//
+//  BracketPairs.swift
+//  CodeEditSourceEditor
+//
+//  Created by Khan Winter on 6/5/25.
+//
+
+enum BracketPairs {
+    static let allValues: [(String, String)] = [
+        ("{", "}"),
+        ("[", "]"),
+        ("(", ")"),
+        ("\"", "\""),
+        ("'", "'")
+    ]
+
+    static let emphasisValues: [(String, String)] = [
+        ("{", "}"),
+        ("[", "]"),
+        ("(", ")")
+    ]
+
+    /// Checks if the given string is a matchable emphasis string.
+    /// - Parameter potentialMatch: The string to check for matches.
+    /// - Returns: True if a match was found with either start or end bracket pairs.
+    static func matches(_ potentialMatch: String) -> Bool {
+        allValues.contains(where: { $0.0 == potentialMatch || $0.1 == potentialMatch })
+    }
+}

Sources/CodeEditSourceEditor/Extensions/DispatchQueue+dispatchMainIfNot.swift

@@ -27,13 +27,11 @@ extension DispatchQueue {
     /// executed if not already on the main thread.
     /// - Parameter item: The work item to execute.
     /// - Returns: The value of the work item.
-    static func syncMainIfNot<T>(_ item: @escaping () -> T) -> T {
+    static func waitMainIfNot<T>(_ item: () -> T) -> T {
         if Thread.isMainThread {
             return item()
         } else {
-            return DispatchQueue.main.sync {
-                return item()
-            }
+            return DispatchQueue.main.asyncAndWait(execute: item)
         }
     }
 }

Sources/CodeEditSourceEditor/Extensions/NSBezierPath+RoundedCorners.swift

@@ -0,0 +1,112 @@
+//
+//  NSBezierPath+RoundedCorners.swift
+//  CodeEditSourceEditor
+//
+//  Created by Khan Winter on 6/3/25.
+//
+
+import AppKit
+
+// Wonderful NSBezierPath extension taken with modification from the playground code at:
+// https://github.com/janheiermann/BezierPath-Corners
+
+extension NSBezierPath {
+    struct Corners: OptionSet {
+        public let rawValue: Int
+
+        public init(rawValue: Corners.RawValue) {
+            self.rawValue = rawValue
+        }
+
+        public static let topLeft = Corners(rawValue: 1 << 0)
+        public static let bottomLeft = Corners(rawValue: 1 << 1)
+        public static let topRight = Corners(rawValue: 1 << 2)
+        public static let bottomRight = Corners(rawValue: 1 << 3)
+        public static let all: Corners = Corners(rawValue: 0b1111)
+    }
+
+    // swiftlint:disable:next function_body_length
+    convenience init(rect: CGRect, roundedCorners corners: Corners, cornerRadius: CGFloat) {
+        self.init()
+
+        let maxX = rect.maxX
+        let minX = rect.minX
+        let maxY = rect.maxY
+        let minY = rect.minY
+        let radius = min(cornerRadius, min(rect.width, rect.height) / 2)
+
+        // Start at bottom-left corner
+        move(to: CGPoint(x: minX + (corners.contains(.bottomLeft) ? radius : 0), y: minY))
+
+        // Bottom edge
+        if corners.contains(.bottomRight) {
+            line(to: CGPoint(x: maxX - radius, y: minY))
+            appendArc(
+                withCenter: CGPoint(x: maxX - radius, y: minY + radius),
+                radius: radius,
+                startAngle: 270,
+                endAngle: 0,
+                clockwise: false
+            )
+        } else {
+            line(to: CGPoint(x: maxX, y: minY))
+        }
+
+        // Right edge
+        if corners.contains(.topRight) {
+            line(to: CGPoint(x: maxX, y: maxY - radius))
+            appendArc(
+                withCenter: CGPoint(x: maxX - radius, y: maxY - radius),
+                radius: radius,
+                startAngle: 0,
+                endAngle: 90,
+                clockwise: false
+            )
+        } else {
+            line(to: CGPoint(x: maxX, y: maxY))
+        }
+
+        // Top edge
+        if corners.contains(.topLeft) {
+            line(to: CGPoint(x: minX + radius, y: maxY))
+            appendArc(
+                withCenter: CGPoint(x: minX + radius, y: maxY - radius),
+                radius: radius,
+                startAngle: 90,
+                endAngle: 180,
+                clockwise: false
+            )
+        } else {
+            line(to: CGPoint(x: minX, y: maxY))
+        }
+
+        // Left edge
+        if corners.contains(.bottomLeft) {
+            line(to: CGPoint(x: minX, y: minY + radius))
+            appendArc(
+                withCenter: CGPoint(x: minX + radius, y: minY + radius),
+                radius: radius,
+                startAngle: 180,
+                endAngle: 270,
+                clockwise: false
+            )
+        } else {
+            line(to: CGPoint(x: minX, y: minY))
+        }
+
+        close()
+    }
+
+    convenience init(roundingRect: CGRect, capTop: Bool, capBottom: Bool, cornerRadius radius: CGFloat) {
+        switch (capTop, capBottom) {
+        case (true, true):
+            self.init(rect: roundingRect)
+        case (false, true):
+            self.init(rect: roundingRect, roundedCorners: [.bottomLeft, .bottomRight], cornerRadius: radius)
+        case (true, false):
+            self.init(rect: roundingRect, roundedCorners: [.topLeft, .topRight], cornerRadius: radius)
+        case (false, false):
+            self.init(roundedRect: roundingRect, xRadius: radius, yRadius: radius)
+        }
+    }
+}