Create struct for segment leaf nodes

lib/src/models/documents/document.dart

@@ -4,6 +4,7 @@ import '../quill_delta.dart';
 import '../rules/rule.dart';
 import '../structs/doc_change.dart';
 import '../structs/offset_value.dart';
+import '../structs/segment_leaf_node.dart';
 import 'attribute.dart';
 import 'history.dart';
 import 'nodes/block.dart';
@@ -215,19 +216,15 @@ class Document {
   }
 
   /// Given offset, find its leaf node in document
-  Tuple2<Line?, Leaf?> querySegmentLeafNode(int offset) {
+  SegmentLeafNode querySegmentLeafNode(int offset) {
     final result = queryChild(offset);
     if (result.node == null) {
-      return const Tuple2(null, null);
+      return const SegmentLeafNode(null, null);
     }
 
     final line = result.node as Line;
     final segmentResult = line.queryChild(result.offset, false);
-    if (segmentResult.node == null) {
-      return Tuple2(line, null);
-    }
-    final segment = segmentResult.node as Leaf;
-    return Tuple2(line, segment);
+    return SegmentLeafNode(line, segmentResult.node as Leaf?);
   }
 
   /// Composes [change] Delta into this document.

lib/src/models/structs/segment_leaf_node.dart

@@ -0,0 +1,8 @@
+import '../../../flutter_quill.dart';
+
+class SegmentLeafNode {
+  const SegmentLeafNode(this.line, this.leaf);
+
+  final Line? line;
+  final Leaf? leaf;
+}

lib/src/widgets/controller.dart

@@ -366,7 +366,7 @@ class QuillController extends ChangeNotifier {
 
   /// Given offset, find its leaf node in document
   Leaf? queryNode(int offset) {
-    return document.querySegmentLeafNode(offset).item2;
+    return document.querySegmentLeafNode(offset).leaf;
   }
 
   /// Clipboard for image url and its corresponding style

lib/src/widgets/editor.dart

@@ -645,11 +645,11 @@ class _QuillEditorSelectionGestureDetectorBuilder
     final pos = renderEditor!.getPositionForOffset(details.globalPosition);
     final result =
         editor!.widget.controller.document.querySegmentLeafNode(pos.offset);
-    final line = result.item1;
+    final line = result.line;
     if (line == null) {
       return false;
     }
-    final segmentLeaf = result.item2;
+    final segmentLeaf = result.leaf;
     if (segmentLeaf == null && line.length == 1) {
       editor!.widget.controller.updateSelection(
           TextSelection.collapsed(offset: pos.offset), ChangeSource.LOCAL);

lib/src/widgets/toolbar/link_style_button.dart

@@ -95,7 +95,7 @@ class _LinkStyleButtonState extends State<LinkStyleButton> {
         if (link != null) {
           // text should be the link's corresponding text, not selection
           final leaf =
-              widget.controller.document.querySegmentLeafNode(index).item2;
+              widget.controller.document.querySegmentLeafNode(index).leaf;
           if (leaf != null) {
             text = leaf.toPlainText();
           }
@@ -126,7 +126,7 @@ class _LinkStyleButtonState extends State<LinkStyleButton> {
     var length = widget.controller.selection.end - index;
     if (_getLinkAttributeValue() != null) {
       // text should be the link's corresponding text, not selection
-      final leaf = widget.controller.document.querySegmentLeafNode(index).item2;
+      final leaf = widget.controller.document.querySegmentLeafNode(index).leaf;
       if (leaf != null) {
         final range = getLinkRange(leaf);
         index = range.start;