Tree: update drag and drop logic (#10372)

packages/tree/src/model/node.js

@@ -168,12 +168,58 @@ export default class Node {
     return getPropertyFromData(this, 'disabled');
   }
 
+  get nextSibling() {
+    const parent = this.parent;
+    if (parent) {
+      const index = parent.childNodes.indexOf(this);
+      if (index > -1) {
+        return parent.childNodes[index + 1];
+      }
+    }
+    return null;
+  }
+
+  get previousSibling() {
+    const parent = this.parent;
+    if (parent) {
+      const index = parent.childNodes.indexOf(this);
+      if (index > -1) {
+        return index > 0 ? parent.childNodes[index - 1] : null;
+      }
+    }
+    return null;
+  }
+
+  contains(target, deep = true) {
+    const walk = function(parent) {
+      const children = parent.childNodes || [];
+      let result = false;
+      for (let i = 0, j = children.length; i < j; i++) {
+        const child = children[i];
+        if (child === target || (deep && walk(child))) {
+          result = true;
+          break;
+        }
+      }
+      return result;
+    };
+
+    return walk(this);
+  }
+
+  remove() {
+    const parent = this.parent;
+    if (parent) {
+      parent.removeChild(this);
+    }
+  }
+
   insertChild(child, index, batch) {
     if (!child) throw new Error('insertChild error: child is required.');
 
     if (!(child instanceof Node)) {
       if (!batch) {
-        const children = this.getChildren() || [];
+        const children = this.getChildren(true);
         if (children.indexOf(child.data) === -1) {
           if (typeof index === 'undefined' || index < 0) {
             children.push(child.data);
@@ -357,7 +403,7 @@ export default class Node {
     }
   }
 
-  getChildren() { // this is data
+  getChildren(forceInit = false) { // this is data
     if (this.level === 0) return this.data;
     const data = this.data;
     if (!data) return null;
@@ -372,6 +418,10 @@ export default class Node {
       data[children] = null;
     }
 
+    if (forceInit && !data[children]) {
+      data[children] = [];
+    }
+
     return data[children];
   }
 

packages/tree/src/model/tree-store.js

@@ -6,11 +6,6 @@ export default class TreeStore {
     this.currentNode = null;
     this.currentNodeKey = null;
 
-    this.dragSourceNode = null;
-    this.dragTargetNode = null;
-    this.dragTargetDom = null;
-    this.allowDrop = true;
-
     for (let option in options) {
       if (options.hasOwnProperty(option)) {
         this[option] = options[option];

packages/tree/src/model/util.js

@@ -14,3 +14,14 @@ export const getNodeKey = function(key, data) {
   if (!key) return data[NODE_KEY];
   return data[key];
 };
+
+export const findNearestComponent = (element, componentName) => {
+  let target = element;
+  while (target && target.tagName !== 'BODY') {
+    if (target.__vue__ && target.__vue__.$options.name === componentName) {
+      return target.__vue__;
+    }
+    target = target.parentNode;
+  }
+  return null;
+};