fix: the problem where text inserted into a node with a leaf node wo…

packages/lexical/src/LexicalSelection.ts

@@ -56,6 +56,7 @@ import {
   getElementByKeyOrThrow,
   getTextNodeOffset,
   INTERNAL_$isBlock,
+  INTERNAL_$isParentLeafElement,
   isSelectionCapturedInDecoratorInput,
   isSelectionWithinEditor,
   removeDOMBlockCursorElement,
@@ -1220,7 +1221,10 @@ export class RangeSelection implements BaseSelection {
     }
 
     const firstPoint = this.isBackward() ? this.focus : this.anchor;
-    const firstBlock = $getAncestor(firstPoint.getNode(), INTERNAL_$isBlock)!;
+    const firstBlock = $getAncestor(
+      firstPoint.getNode(),
+      INTERNAL_$isParentLeafElement,
+    )!;
 
     const last = nodes[nodes.length - 1]!;
 
@@ -2744,7 +2748,7 @@ function $removeTextAndSplitBlock(selection: RangeSelection): number {
   let node = anchor.getNode();
   let offset = anchor.offset;
 
-  while (!INTERNAL_$isBlock(node)) {
+  while (!INTERNAL_$isParentLeafElement(node)) {
     [node, offset] = $splitNodeAtPoint(node, offset);
   }
 

packages/lexical/src/LexicalUtils.ts

@@ -1695,6 +1695,26 @@ export function INTERNAL_$isBlock(
   return !node.isInline() && node.canBeEmpty() !== false && isLeafElement;
 }
 
+export function INTERNAL_$isParentLeafElement(
+  node: LexicalNode,
+): node is ElementNode | DecoratorNode<unknown> {
+  if ($isRootNode(node) || ($isDecoratorNode(node) && !node.isInline())) {
+    return true;
+  }
+  if (!$isElementNode(node) || $isRootOrShadowRoot(node)) {
+    return false;
+  }
+
+  const firstChild = node.getFirstChild();
+  const isLeafElement =
+    firstChild === null ||
+    $isLineBreakNode(firstChild) ||
+    $isTextNode(firstChild) ||
+    firstChild.isInline();
+
+  return isLeafElement;
+}
+
 export function $getAncestor<NodeType extends LexicalNode = LexicalNode>(
   node: LexicalNode,
   predicate: (ancestor: LexicalNode) => ancestor is NodeType,