refactor(core): remove null as return type of data in useNodesData (#1575)

* refactor(core): remove `null` as return type of data

Signed-off-by: braks <78412429+bcakmakoglu@users.noreply.github.com>

* chore(changeset): add

Signed-off-by: braks <78412429+bcakmakoglu@users.noreply.github.com>

---------

Signed-off-by: braks <78412429+bcakmakoglu@users.noreply.github.com>

Author: bcakmakoglu

.changeset/real-pugs-guess.md

@@ -0,0 +1,5 @@
+---
+"@vue-flow/core": minor
+---
+
+Remove `null` as possible return type of data in `useNodesData`

packages/core/src/composables/useNodesData.ts

@@ -7,7 +7,7 @@ import { useVueFlow } from './useVueFlow'
 interface NodeData<NodeType extends Node = GraphNode> {
   id: string
   type: NodeType['type']
-  data: NonNullable<NodeType['data']> | null
+  data: NonNullable<NodeType['data']>
 }
 
 /**
@@ -42,7 +42,7 @@ export function useNodesData(_nodeIds: any): any {
           return {
             id: node.id,
             type: node.type,
-            data: node.data ?? null,
+            data: node.data,
           }
         }
 
@@ -58,7 +58,7 @@ export function useNodesData(_nodeIds: any): any {
           data.push({
             id: node.id,
             type: node.type,
-            data: node.data ?? null,
+            data: node.data,
           })
         }
       }