Fix Warnings, Add Test Case

Author: thecoolwinter

Sources/CodeEditTextView/EmphasisManager/EmphasisManager.swift

@@ -70,7 +70,7 @@ public final class EmphasisManager {
         handleSelections(for: emphases)
 
         // Handle flash animations
-        for flashingLayer in emphasisGroups[id, default: []].filter { $0.emphasis.flash } {
+        for flashingLayer in emphasisGroups[id, default: []].filter({ $0.emphasis.flash }) {
             DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
                 guard let self = self else { return }
                 self.applyFadeOutAnimation(to: flashingLayer.layer, textLayer: flashingLayer.textLayer) {
@@ -204,7 +204,7 @@ public final class EmphasisManager {
             }
             let lineHeight = layoutManager.estimateLineHeight()
             let lineBottomPadding = (lineHeight - (lineHeight / layoutManager.lineHeightMultiplier)) / 4
-            var path = NSBezierPath()
+            let path = NSBezierPath()
             for rect in layoutManager.rectsFor(range: range) {
                 path.move(to: NSPoint(x: rect.minX, y: rect.maxY - lineBottomPadding))
                 path.line(to: NSPoint(x: rect.maxX, y: rect.maxY - lineBottomPadding))

Sources/CodeEditTextView/TextLayoutManager/TextLayoutManager+Public.swift

@@ -172,9 +172,7 @@ extension TextLayoutManager {
 
         // Don't make rects in between characters
         let realRangeStart = textStorage.rangeOfComposedCharacterSequence(at: range.lowerBound)
-        ?? NSRange(location: range.lowerBound, length: 0)
         let realRangeEnd = textStorage.rangeOfComposedCharacterSequence(at: range.upperBound - 1)
-        ?? NSRange(location: range.upperBound - 1, length: 0)
 
         // Fragments are relative to the line
         let relativeRange = NSRange(

Sources/CodeEditTextView/TextLayoutManager/TextLayoutManager.swift

@@ -212,8 +212,7 @@ public class TextLayoutManager: NSObject {
     /// Lays out all visible lines
     func layoutLines(in rect: NSRect? = nil) { // swiftlint:disable:this function_body_length
         assertNotInLayout()
-        guard layoutView?.superview != nil,
-              let visibleRect = rect ?? delegate?.visibleRect,
+        guard let visibleRect = rect ?? delegate?.visibleRect,
               !isInTransaction,
               let textStorage else {
             return

Tests/CodeEditTextViewTests/EmphasisManagerTests.swift

@@ -0,0 +1,36 @@
+import Testing
+import Foundation
+@testable import CodeEditTextView
+
+@Suite()
+struct EmphasisManagerTests {
+    @Test() @MainActor
+    func testFlashEmphasisLayersNotLeaked() {
+        // Ensure layers are not leaked when switching from flash emphasis to any other emphasis type.
+        let textView = TextView(string: "Lorem Ipsum")
+        textView.frame = NSRect(x: 0, y: 0, width: 1000, height: 100)
+        textView.layoutManager.layoutLines(in: CGRect(origin: .zero, size: CGSize(width: 1000, height: 100)))
+        textView.emphasisManager?.addEmphasis(
+            Emphasis(range: NSRange(location: 0, length: 5), style: .standard, flash: true),
+            for: "e"
+        )
+
+        // Text layer and emphasis layer
+        #expect(textView.layer?.sublayers?.count == 2)
+        #expect(textView.emphasisManager?.getEmphases(for: "e").count == 1)
+
+        textView.emphasisManager?.replaceEmphases(
+            [Emphasis(range: NSRange(location: 0, length: 5), style: .underline(color: .red), flash: false)],
+            for: "e"
+        )
+
+        #expect(textView.layer?.sublayers?.count == 2)
+        #expect(textView.emphasisManager?.getEmphases(for: "e").count == 1)
+
+        textView.emphasisManager?.removeAllEmphases()
+
+        // No emphases
+        #expect(textView.layer?.sublayers?.count == nil)
+        #expect(textView.emphasisManager?.getEmphases(for: "e").count == 0)
+    }
+}