chore: add additional check for pointer before slice

Author: DmitryAnansky

packages/core/src/format/codeframes.ts

@@ -176,7 +176,9 @@ function positionsToLoc(
 }
 
 export function getAstNodeByPointer(root: YAMLNode, pointer: string, reportOnKey: boolean) {
-  const pointerSegments = parsePointer(pointer).slice(1);
+  const segments = parsePointer(pointer);
+  const pointerSegments = segments[0] === '#' ? segments.slice(1) : segments;
+
   if (root === undefined) {
     return undefined;
   }