Add Invalidated Layout Test, Delegate Editing Test, Remove Layout Manager Assertion

Author: thecoolwinter

Sources/CodeEditTextView/TextLayoutManager/TextLayoutManager.swift

@@ -201,25 +201,13 @@ public class TextLayoutManager: NSObject {
 
     // MARK: - Layout
 
-    /// Asserts that the caller is not in an active layout pass.
-    /// See docs on ``isInLayout`` for more details.
-    private func assertNotInLayout() {
-        #if DEBUG // This is redundant, but it keeps the flag debug-only too which helps prevent misuse.
-        assert(!isInLayout, "layoutLines called while already in a layout pass. This is a programmer error.")
-        #endif
-    }
-
     /// Lays out all visible lines
     func layoutLines(in rect: NSRect? = nil) { // swiftlint:disable:this function_body_length
-//        assertNotInLayout()
         guard let visibleRect = rect ?? delegate?.visibleRect,
               !isInTransaction,
               let textStorage else {
             return
         }
-//        #if DEBUG
-//        isInLayout = true
-//        #endif
         let minY = max(visibleRect.minY - verticalLayoutPadding, 0)
         let maxY = max(visibleRect.maxY + verticalLayoutPadding, 0)
         let originalHeight = lineStorage.height
@@ -271,10 +259,6 @@ public class TextLayoutManager: NSObject {
         // Update the visible lines with the new set.
         visibleLineIds = newVisibleLines
 
-//        #if DEBUG
-//        isInLayout = false
-//        #endif
-
         // These are fine to update outside of `isInLayout` as our internal data structures are finalized at this point
         // so laying out again won't break our line storage or visible line.
 

Tests/CodeEditTextViewTests/EmphasisManagerTests.swift

@@ -4,7 +4,8 @@ import Foundation
 
 @Suite()
 struct EmphasisManagerTests {
-    @Test() @MainActor
+    @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")

Tests/CodeEditTextViewTests/TextLayoutManagerTests.swift

@@ -42,6 +42,7 @@ struct TextLayoutManagerTests {
 
     init() throws {
         textView = TextView(string: "A\nB\nC\nD")
+        textView.frame = NSRect(x: 0, y: 0, width: 1000, height: 1000)
         textStorage = textView.textStorage
         layoutManager = try #require(textView.layoutManager)
     }
@@ -99,4 +100,34 @@ struct TextLayoutManagerTests {
         #expect(layoutManager.lineStorage.length == textStorage.length)
         layoutManager.lineStorage.validateInternalState()
     }
+
+    /// # 04/09/25
+    /// This ensures that getting line rect info does not invalidate layout. The issue was previously caused by a call to
+    /// ``TextLayoutManager/preparePositionForDisplay``.
+    @Test
+    func getRectsDoesNotRemoveLayoutInfo() {
+        layoutManager.layoutLines(in: NSRect(x: 0, y: 0, width: 1000, height: 1000))
+        let lineFragmentIDs = Set(
+            layoutManager.lineStorage
+                .linesInRange(NSRange(location: 0, length: 7))
+                .flatMap(\.data.lineFragments)
+                .map(\.data.id)
+        )
+
+        _ = layoutManager.rectsFor(range: NSRange(start: 0, end: 7))
+
+        #expect(
+            layoutManager.lineStorage.linesInRange(NSRange(location: 0, length: 7)).allSatisfy({ position in
+                !position.data.lineFragments.isEmpty
+            })
+        )
+        let afterLineFragmentIDs = Set(
+            layoutManager.lineStorage
+                .linesInRange(NSRange(location: 0, length: 7))
+                .flatMap(\.data.lineFragments)
+                .map(\.data.id)
+        )
+        #expect(lineFragmentIDs == afterLineFragmentIDs, "Line fragments were invalidated by `rectsFor(range:)` call.")
+        layoutManager.lineStorage.validateInternalState()
+    }
 }

Tests/CodeEditTextViewTests/TextViewTests.swift

@@ -0,0 +1,43 @@
+import Testing
+import AppKit
+@testable import CodeEditTextView
+
+@Suite
+@MainActor
+struct TextViewTests {
+    class MockDelegate: TextViewDelegate {
+        var shouldReplaceContents: ((_ textView: TextView, _ range: NSRange, _ string: String) -> Bool)?
+
+        func textView(_ textView: TextView, shouldReplaceContentsIn range: NSRange, with string: String) -> Bool {
+            shouldReplaceContents?(textView, range, string) ?? true
+        }
+    }
+
+    let textView: TextView
+    let delegate: MockDelegate
+
+    init() {
+        textView = TextView(string: "Lorem Ipsum")
+        delegate = MockDelegate()
+        textView.delegate = delegate
+    }
+
+    @Test
+    func delegateChangesText() {
+        var hasReplaced = false
+        delegate.shouldReplaceContents = { textView, _, _ -> Bool in
+            if !hasReplaced {
+                hasReplaced.toggle()
+                textView.replaceCharacters(in: NSRange(location: 0, length: 0), with: " World ")
+            }
+
+            return true
+        }
+
+        textView.replaceCharacters(in: NSRange(location: 0, length: 0), with: "Hello")
+
+        #expect(textView.string == "Hello World Lorem Ipsum")
+        // available in test module
+        textView.layoutManager.lineStorage.validateInternalState()
+    }
+}