Collapsed Colors, Clean Up and Document

Author: thecoolwinter

Sources/CodeEditSourceEditor/LineFolding/View/FoldingRibbonView+Draw.swift

@@ -15,6 +15,8 @@ extension FoldingRibbonView {
         let endLine: TextLineStorage<TextLine>.TextLinePosition
     }
 
+    // MARK: - Draw
+
     override func draw(_ dirtyRect: NSRect) {
         guard let context = NSGraphicsContext.current?.cgContext,
               let layoutManager = model?.controller?.textView.layoutManager else {
@@ -53,6 +55,20 @@ extension FoldingRibbonView {
         context.restoreGState()
     }
 
+    // MARK: - Get Drawing Folds
+    
+    /// Generates drawable fold info for a range of text.
+    ///
+    /// The fold storage intentionally does not store the full ranges of all folds at each interval. We may, for an
+    /// interval, find that we only receive fold information for depths > 1. In this case, we still need to draw those
+    /// layers of color to create the illusion that those folds are continuous under the nested folds. To achieve this,
+    /// we create 'fake' folds that span more than the queried text range. When returned for drawing, the drawing
+    /// methods will draw those extra folds normally.
+    ///
+    /// - Parameters:
+    ///   - textRange: The range of characters in text to create drawing fold info for.
+    ///   - layoutManager: A layout manager to query for line layout information.
+    /// - Returns: A list of folds to draw for the given text range.
     private func getDrawingFolds(
         forTextRange textRange: Range<Int>,
         layoutManager: TextLayoutManager
@@ -123,6 +139,8 @@ extension FoldingRibbonView {
         }
     }
 
+    // MARK: - Collapsed Fold
+
     private func drawCollapsedFold(
         minYPosition: CGFloat,
         maxYPosition: CGFloat,
@@ -144,19 +162,21 @@ extension FoldingRibbonView {
         chevron.addLine(to: CGPoint(x: maxX, y: centerY))
         chevron.addLine(to: CGPoint(x: minX, y: maxY))
 
-        context.setStrokeColor(NSColor.secondaryLabelColor.cgColor)
+        context.setStrokeColor(foldedIndicatorChevronColor)
         context.setLineCap(.round)
         context.setLineJoin(.round)
         context.setLineWidth(1.3)
 
-        context.setFillColor(NSColor.tertiaryLabelColor.cgColor)
+        context.setFillColor(foldedIndicatorColor)
         context.fill(fillRect)
         context.addPath(chevron)
         context.strokePath()
 
         context.restoreGState()
     }
 
+    // MARK: - Hovered Fold
+
     private func drawHoveredFold(
         minYPosition: CGFloat,
         maxYPosition: CGFloat,
@@ -203,6 +223,8 @@ extension FoldingRibbonView {
         context.restoreGState()
     }
 
+    // MARK: - Nested Fold
+
     private func drawNestedFold(
         foldInfo: DrawingFoldInfo,
         foldCaps: FoldCapInfo,
@@ -241,6 +263,8 @@ extension FoldingRibbonView {
         context.restoreGState()
     }
 
+    // MARK: - Nested Outline
+
     /// Draws a rounded outline for a rectangle, creating the small, light, outline around each fold indicator.
     ///
     /// This function does not change fill colors for the given context.

Sources/CodeEditSourceEditor/LineFolding/View/FoldingRibbonView+FoldCapInfo.swift

@@ -8,6 +8,8 @@
 import AppKit
 
 extension FoldingRibbonView {
+    /// A helper type that determines if a fold should be drawn with a cap on the top or bottom if
+    /// there's an adjacent fold on the same text line. It also provides a helper method
     struct FoldCapInfo {
         let startIndices: Set<Int>
         let endIndices: Set<Int>
@@ -32,13 +34,15 @@ extension FoldingRibbonView {
             let capTop = foldNeedsTopCap(fold)
             let capBottom = foldNeedsBottomCap(fold)
             let yDelta = capTop ? fold.startLine.height / 2.0 : 0.0
-            let heightDelta: CGFloat = if capTop && capBottom {
-                -fold.startLine.height
-            } else if capTop || capBottom {
-                -(fold.startLine.height / 2.0)
-            } else {
-                0.0
+
+            var heightDelta: CGFloat = 0.0
+            if capTop {
+                heightDelta -= fold.startLine.height / 2.0
+            }
+            if capBottom {
+                heightDelta -= fold.endLine.height / 2.0
             }
+
             return NSRect(
                 x: rect.origin.x,
                 y: rect.origin.y + yDelta,

Sources/CodeEditSourceEditor/LineFolding/View/FoldingRibbonView.swift

@@ -10,6 +10,21 @@ import AppKit
 import CodeEditTextView
 import Combine
 
+extension NSColor {
+    convenience init(light: NSColor, dark: NSColor) {
+        self.init(name: nil) { appearance in
+            return switch appearance.name {
+            case .aqua:
+                light
+            case .darkAqua:
+                dark
+            default:
+                NSColor()
+            }
+        }
+    }
+}
+
 /// Displays the code folding ribbon in the ``GutterView``.
 ///
 /// This view draws its contents
@@ -33,52 +48,37 @@ class FoldingRibbonView: NSView {
     var backgroundColor: NSColor = NSColor.controlBackgroundColor
 
     @Invalidating(.display)
-    var markerColor = NSColor(name: nil) { appearance in
-        return switch appearance.name {
-        case .aqua:
-            NSColor(deviceWhite: 0.0, alpha: 0.1)
-        case .darkAqua:
-            NSColor(deviceWhite: 1.0, alpha: 0.2)
-        default:
-            NSColor()
-        }
-    }.cgColor
+    var markerColor = NSColor(
+        light: NSColor(deviceWhite: 0.0, alpha: 0.1),
+        dark: NSColor(deviceWhite: 1.0, alpha: 0.2)
+    ).cgColor
 
     @Invalidating(.display)
-    var markerBorderColor = NSColor(name: nil) { appearance in
-        return switch appearance.name {
-        case .aqua:
-            NSColor(deviceWhite: 1.0, alpha: 0.4)
-        case .darkAqua:
-            NSColor(deviceWhite: 0.0, alpha: 0.4)
-        default:
-            NSColor()
-        }
-    }.cgColor
+    var markerBorderColor = NSColor(
+        light: NSColor(deviceWhite: 1.0, alpha: 0.4),
+        dark: NSColor(deviceWhite: 0.0, alpha: 0.4)
+    ).cgColor
 
     @Invalidating(.display)
-    var hoverFillColor = NSColor(name: nil) { appearance in
-        return switch appearance.name {
-        case .aqua:
-            NSColor(deviceWhite: 1.0, alpha: 1.0)
-        case .darkAqua:
-            NSColor(deviceWhite: 0.17, alpha: 1.0)
-        default:
-            NSColor()
-        }
-    }.cgColor
+    var hoverFillColor = NSColor(
+        light: NSColor(deviceWhite: 1.0, alpha: 1.0),
+        dark: NSColor(deviceWhite: 0.17, alpha: 1.0)
+    ).cgColor
 
     @Invalidating(.display)
-    var hoverBorderColor = NSColor(name: nil) { appearance in
-        return switch appearance.name {
-        case .aqua:
-            NSColor(deviceWhite: 0.8, alpha: 1.0)
-        case .darkAqua:
-            NSColor(deviceWhite: 0.4, alpha: 1.0)
-        default:
-            NSColor()
-        }
-    }.cgColor
+    var hoverBorderColor = NSColor(
+        light: NSColor(deviceWhite: 0.8, alpha: 1.0),
+        dark: NSColor(deviceWhite: 0.4, alpha: 1.0)
+    ).cgColor
+
+    @Invalidating(.display)
+    var foldedIndicatorColor = NSColor(
+        light: NSColor(deviceWhite: 0.0, alpha: 0.3),
+        dark: NSColor(deviceWhite: 1.0, alpha: 0.6)
+    ).cgColor
+
+    @Invalidating(.display)
+    var foldedIndicatorChevronColor = NSColor.secondaryLabelColor.cgColor
 
     override public var isFlipped: Bool {
         true