perf: add truthProp util (#8522)

* perf: add TruthyProp util

* chore: rename

* chore: upd

src/list/List.tsx

@@ -9,7 +9,7 @@ import {
 } from 'vue';
 
 // Utils
-import { isHidden, createNamespace } from '../utils';
+import { isHidden, truthProp, createNamespace } from '../utils';
 
 // Composables
 import { useRect, useScrollParent, useEventListener } from '@vant/use';
@@ -30,6 +30,7 @@ export default defineComponent({
     errorText: String,
     loadingText: String,
     finishedText: String,
+    immediateCheck: truthProp,
     offset: {
       type: [Number, String],
       default: 300,
@@ -38,10 +39,6 @@ export default defineComponent({
       type: String as PropType<'up' | 'down'>,
       default: 'down',
     },
-    immediateCheck: {
-      type: Boolean,
-      default: true,
-    },
   },
 
   emits: ['load', 'update:error', 'update:loading'],