fix: antd-issue-51248

src/hooks/useSearchConfig.ts

@@ -1,3 +1,4 @@
+
 import warning from 'rc-util/lib/warning';
 import * as React from 'react';
 import type { CascaderProps, ShowSearchType } from '../Cascader';
@@ -22,7 +23,7 @@ export default function useSearchConfig(showSearch?: CascaderProps['showSearch']
     }
 
     if ((searchConfig.limit as number) <= 0) {
-      delete searchConfig.limit;
+      searchConfig.limit = false;
 
       if (process.env.NODE_ENV !== 'production') {
         warning(false, "'limit' of showSearch should be positive number or false.");

tests/search.limit.spec.tsx

@@ -0,0 +1,46 @@
+import React from 'react';
+import Cascader from '../src';
+import type { ReactWrapper } from './enzyme';
+import { mount } from './enzyme';
+
+describe('Cascader.Search', () => {
+  function doSearch(wrapper: ReactWrapper, search: string) {
+    wrapper.find('input').simulate('change', {
+      target: {
+        value: search,
+      },
+    });
+  }
+  const options = [
+    {
+      region: 'Asia',
+      children: [],
+      isParent: true,
+      label: 'Asia',
+      value: 'Asia',
+    },
+  ];
+  for (let i = 0; i < 100; i++) {
+    options[0].children.push({
+      id: i,
+      label: 'label' + i,
+      value: 'value' + i,
+    });
+  }
+
+  it('limit', () => {
+    const wrapper = mount(
+      <Cascader
+        options={options}
+        open
+        showSearch={{
+          limit: false,
+        }}
+      />,
+    );
+
+    doSearch(wrapper, 'as');
+    const itemList = wrapper.find('div.rc-cascader-menu-item-content');
+    expect(itemList).toHaveLength(itemList.length);
+  });
+});