diff --git a/Sources/CodeEditSourceEditor/Highlighting/HighlighProviding/HighlightProviderState.swift b/Sources/CodeEditSourceEditor/Highlighting/HighlighProviding/HighlightProviderState.swift
index 6fca2123b..8b42ba229 100644
--- a/Sources/CodeEditSourceEditor/Highlighting/HighlighProviding/HighlightProviderState.swift
+++ b/Sources/CodeEditSourceEditor/Highlighting/HighlighProviding/HighlightProviderState.swift
@@ -139,8 +139,9 @@ extension HighlightProviderState {
         highlightProvider?.applyEdit(textView: textView, range: range, delta: delta) { [weak self] result in
             switch result {
             case .success(let invalidSet):
+                let modifiedRange = NSRange(location: range.location, length: range.length + delta)
                 // Make sure we add in the edited range too
-                self?.invalidate(invalidSet.union(IndexSet(integersIn: range)))
+                self?.invalidate(invalidSet.union(IndexSet(integersIn: modifiedRange)))
             case .failure(let error):
                 if case HighlightProvidingError.operationCancelled = error {
                     self?.invalidate(IndexSet(integersIn: range))
diff --git a/Tests/CodeEditSourceEditorTests/Highlighting/HighlightProviderStateTest.swift b/Tests/CodeEditSourceEditorTests/Highlighting/HighlightProviderStateTest.swift
index d3f89f0cc..e730e16de 100644
--- a/Tests/CodeEditSourceEditorTests/Highlighting/HighlightProviderStateTest.swift
+++ b/Tests/CodeEditSourceEditorTests/Highlighting/HighlightProviderStateTest.swift
@@ -116,12 +116,13 @@ final class HighlightProviderStateTest: XCTestCase {
             language: .swift
         )
 
+        // These reflect values like `NSTextStorage` outputs, and differ from ranges used in other tests.
         let mockEdits: [(NSRange, Int)] = [
-            (NSRange(location: 0, length: 10), 10), // Inserted 10
-            (NSRange(location: 5, length: 0), -2), // Deleted 2 at 5
-            (NSRange(location: 0, length: 2), 3), // Replaced 0-2 with 3
+            (NSRange(location: 0, length: 0), 10), // Inserted 10
+            (NSRange(location: 3, length: 2), -2), // Deleted 2 at 5
+            (NSRange(location: 0, length: 2), 1),  // Replaced 0-2 with 3
             (NSRange(location: 9, length: 1), 1),
-            (NSRange(location: 0, length: 0), -10)
+            (NSRange(location: 0, length: 10), -10)
         ]
 
         for edit in mockEdits {