fix(tree): support defaultExpandAll prop

defaultExpandLevel已去除-1的行为定义，由defaultExpandAll代替。

src/components/Tree/src/Tree.vue

@@ -211,12 +211,11 @@
       });
 
       onMounted(() => {
-        if (props.defaultExpandLevel === '') return;
         const level = parseInt(props.defaultExpandLevel);
-        if (level === -1) {
-          expandAll(true);
-        } else if (level > 0) {
+        if (level > 0) {
           state.expandedKeys = filterByLevel(level);
+        } else if (props.defaultExpandAll) {
+          expandAll(true);
         }
       });
 

src/components/Tree/src/props.ts

@@ -27,6 +27,7 @@ export const basicProps = {
     type: [String, Number] as PropType<string | number>,
     default: '',
   },
+  defaultExpandAll: propTypes.bool.def(false),
 
   replaceFields: {
     type: Object as PropType<ReplaceFields>,

src/views/demo/tree/index.vue

@@ -13,7 +13,7 @@
         title="可勾选，默认全部展开"
         :checkable="true"
         class="w-1/3 mx-4"
-        defaultExpandLevel="-1"
+        defaultExpandAll
         @check="handleCheck"
       />