fix(Cascader): incorrect selection behavior in single selection mode

packages/components/cascader/core/effect.ts

@@ -1,6 +1,6 @@
-import { isNumber, isFunction, cloneDeep } from 'lodash-es';
-import { TreeNode, CascaderContextType, TdCascaderProps, TreeNodeValue, TreeNodeModel } from '../interface';
+import { cloneDeep, isFunction, isNumber } from 'lodash-es';
 import { getFullPathLabel, getTreeValue } from './helper';
+import type { CascaderContextType, TdCascaderProps, TreeNode, TreeNodeModel, TreeNodeValue } from '../interface';
 
 /**
  * 点击item的副作用
@@ -47,8 +47,10 @@ export function expendClickEffect(
   }
 
   if (!multiple && (node.isLeaf() || checkStrictly) && trigger === 'click') {
+    if (node.checked) return;
+
     treeStore.resetChecked();
-    const checked = node.setChecked(!node.checked);
+    const checked = node.setChecked(true);
     const [value] = checked;
 
     // 非受控状态下更新状态

packages/components/cascader/core/helper.ts

@@ -1,9 +1,9 @@
 import { isEmpty } from 'lodash-es';
-import {
-  TreeNode,
+import type {
   CascaderContextType,
-  TdCascaderProps,
   CascaderValue,
+  TdCascaderProps,
+  TreeNode,
   TreeNodeValue,
   TreeOptionData,
 } from '../interface';
@@ -141,6 +141,25 @@ export function isEmptyValues(value: unknown): boolean {
  * @returns boolean
  */
 export function isValueInvalid(value: CascaderValue, cascaderContext: CascaderContextType) {
-  const { multiple, showAllLevels } = cascaderContext;
-  return (multiple && !Array.isArray(value)) || (!multiple && Array.isArray(value) && !showAllLevels);
+  const { multiple, showAllLevels, valueType } = cascaderContext;
+
+  // 多选模式：
+  // value 必须是数组
+  if (multiple) {
+    return !Array.isArray(value);
+  }
+
+  // 单选模式：
+  // valueType === 'full' 时，使用完整路径数组
+  if (valueType === 'full') {
+    return !Array.isArray(value);
+  }
+
+  // 其它情况默认 value 为非数组
+  // 若是数组，仅在 showAllLevels=true 时合法
+  if (Array.isArray(value)) {
+    return !showAllLevels;
+  }
+
+  return false;
 }

packages/components/form/FormItem.tsx

@@ -420,7 +420,7 @@ const FormItem = forwardRef<FormItemInstance, FormItemProps>((originalProps, ref
 
     const isFormList = formListName && isSameForm;
     const mapRef = isFormList ? formListMapRef : formMapRef;
-    if (!mapRef.current) return;
+    if (!mapRef?.current) return;
 
     // 注册实例
     mapRef.current.set(fullPath, formItemRef);