From a65d218e2220d73cbb9c93b34f488e71dfbc9039 Mon Sep 17 00:00:00 2001
From: Zhong <cszhjh@gmail.com>
Date: Mon, 20 Oct 2025 14:43:47 +0800
Subject: [PATCH] refactor(components): [tree] improve emit to get type hints
 (#22526)

* refactor(components): [tree] improve emit to get type hints

* chore: update

* fix: update

* chore: revert example

* docs: update type

Co-authored-by: Dsaquel <291874700n@gmail.com>

* chore: rename event

Co-authored-by: btea <2356281422@qq.com>

---------

Co-authored-by: Dsaquel <291874700n@gmail.com>
Co-authored-by: btea <2356281422@qq.com>
---
 docs/examples/tree/draggable.vue              | 25 +++-----
 packages/components/tree/index.ts             |  1 +
 .../components/tree/src/model/useDragNode.ts  | 15 +++--
 packages/components/tree/src/model/util.ts    |  4 +-
 packages/components/tree/src/tree.ts          | 58 +++++++++++++++++++
 packages/components/tree/src/tree.type.ts     | 10 +++-
 packages/components/tree/src/tree.vue         | 17 +-----
 7 files changed, 91 insertions(+), 39 deletions(-)
 create mode 100644 packages/components/tree/src/tree.ts

diff --git a/docs/examples/tree/draggable.vue b/docs/examples/tree/draggable.vue
index b9dca53a84..8d1420735a 100644
--- a/docs/examples/tree/draggable.vue
+++ b/docs/examples/tree/draggable.vue
@@ -19,46 +19,37 @@
 <script lang="ts" setup>
 import type {
   AllowDropType,
-  DragEvents,
   NodeDropType,
   RenderContentContext,
 } from 'element-plus'
 
 type Node = RenderContentContext['node']
 
-const handleDragStart = (node: Node, ev: DragEvents) => {
+const handleDragStart = (node: Node, ev: DragEvent) => {
   console.log('drag start', node)
 }
-const handleDragEnter = (
-  draggingNode: Node,
-  dropNode: Node,
-  ev: DragEvents
-) => {
+const handleDragEnter = (draggingNode: Node, dropNode: Node, ev: DragEvent) => {
   console.log('tree drag enter:', dropNode.label)
 }
-const handleDragLeave = (
-  draggingNode: Node,
-  dropNode: Node,
-  ev: DragEvents
-) => {
+const handleDragLeave = (draggingNode: Node, dropNode: Node, ev: DragEvent) => {
   console.log('tree drag leave:', dropNode.label)
 }
-const handleDragOver = (draggingNode: Node, dropNode: Node, ev: DragEvents) => {
+const handleDragOver = (draggingNode: Node, dropNode: Node, ev: DragEvent) => {
   console.log('tree drag over:', dropNode.label)
 }
 const handleDragEnd = (
   draggingNode: Node,
-  dropNode: Node,
+  dropNode: Node | null,
   dropType: NodeDropType,
-  ev: DragEvents
+  ev: DragEvent
 ) => {
   console.log('tree drag end:', dropNode && dropNode.label, dropType)
 }
 const handleDrop = (
   draggingNode: Node,
   dropNode: Node,
-  dropType: NodeDropType,
-  ev: DragEvents
+  dropType: Exclude<NodeDropType, 'none'>,
+  ev: DragEvent
 ) => {
   console.log('tree drop:', dropNode.label, dropType)
 }
diff --git a/packages/components/tree/index.ts b/packages/components/tree/index.ts
index 67f78ea2ec..3bce918e99 100644
--- a/packages/components/tree/index.ts
+++ b/packages/components/tree/index.ts
@@ -10,3 +10,4 @@ export default ElTree
 export * from './src/tree.type'
 export * from './src/instance'
 export * from './src/tokens'
+export * from './src/tree'
diff --git a/packages/components/tree/src/model/useDragNode.ts b/packages/components/tree/src/model/useDragNode.ts
index b424f6f991..cc0e89eb2f 100644
--- a/packages/components/tree/src/model/useDragNode.ts
+++ b/packages/components/tree/src/model/useDragNode.ts
@@ -11,6 +11,7 @@ import type {
 } from '../tree.type'
 import type TreeStore from './tree-store'
 import type Node from './node'
+import type { treeEmits } from '../tree'
 
 interface TreeNode {
   node: Node
@@ -27,7 +28,7 @@ interface Props {
     allowDrag?: AllowDragFunction
     allowDrop?: AllowDropFunction
   }
-  ctx: SetupContext<string[]>
+  ctx: SetupContext<typeof treeEmits>
   el$: Ref<HTMLElement | null>
   dropIndicator$: Ref<HTMLElement | null>
   store: Ref<TreeStore>
@@ -242,15 +243,21 @@ export function useDragNodeHandler({
         'node-drag-end',
         draggingNode.node,
         dropNode.node,
-        dropType,
+        dropType!,
         event
       )
       if (dropType !== 'none') {
-        ctx.emit('node-drop', draggingNode.node, dropNode.node, dropType, event)
+        ctx.emit(
+          'node-drop',
+          draggingNode.node,
+          dropNode.node,
+          dropType!,
+          event
+        )
       }
     }
     if (draggingNode && !dropNode) {
-      ctx.emit('node-drag-end', draggingNode.node, null, dropType, event)
+      ctx.emit('node-drag-end', draggingNode.node, null, dropType!, event)
     }
 
     dragState.value.showDropIndicator = false
diff --git a/packages/components/tree/src/model/util.ts b/packages/components/tree/src/model/util.ts
index 98aa74ae2f..ad5211f457 100644
--- a/packages/components/tree/src/model/util.ts
+++ b/packages/components/tree/src/model/util.ts
@@ -1,5 +1,5 @@
-import type { SetupContext } from 'vue'
 import type Node from './node'
+import type { TreeEmits } from '../tree'
 import type { RootTreeType, TreeKey, TreeNodeData } from '../tree.type'
 
 export const NODE_KEY = '$treeNodeId'
@@ -22,7 +22,7 @@ export const getNodeKey = (key: TreeKey | undefined, data: TreeNodeData) =>
 
 export const handleCurrentChange = (
   store: RootTreeType['store'],
-  emit: SetupContext['emit'],
+  emit: TreeEmits,
   setCurrent: () => void
 ) => {
   const preCurrentNode = store.value.currentNode
diff --git a/packages/components/tree/src/tree.ts b/packages/components/tree/src/tree.ts
new file mode 100644
index 0000000000..bad28879fa
--- /dev/null
+++ b/packages/components/tree/src/tree.ts
@@ -0,0 +1,58 @@
+import { isBoolean } from '@element-plus/utils'
+
+import type { ComponentInternalInstance } from 'vue'
+import type { EmitFn } from '@element-plus/utils'
+import type Node from './model/node'
+import type { CheckedInfo, NodeDropType } from './tree.type'
+
+/* eslint-disable @typescript-eslint/no-unused-vars */
+export const treeEmits = {
+  'check-change': (data: any, checked: boolean, indeterminate: boolean) =>
+    data && isBoolean(checked) && isBoolean(indeterminate),
+  'current-change': (data: any | null, node: Node | null) => true,
+  'node-click': (
+    data: any,
+    node: Node,
+    nodeInstance: ComponentInternalInstance | null,
+    evt: MouseEvent
+  ) => data && node && evt instanceof Event,
+  'node-contextmenu': (
+    evt: Event,
+    data: any,
+    node: Node,
+    nodeInstance: ComponentInternalInstance | null
+  ) => evt instanceof Event && data && node,
+  'node-collapse': (
+    data: any,
+    node: Node,
+    nodeInstance: ComponentInternalInstance | null
+  ) => data && node,
+  'node-expand': (
+    data: any,
+    node: Node,
+    nodeInstance: ComponentInternalInstance | null
+  ) => data && node,
+  check: (data: any, checkedInfo: CheckedInfo) => data && checkedInfo,
+  'node-drag-start': (node: Node, evt: DragEvent) => node && evt,
+  'node-drag-end': (
+    draggingNode: Node,
+    dropNode: Node | null,
+    dropType: NodeDropType,
+    evt: DragEvent
+  ) => draggingNode && evt,
+  'node-drop': (
+    draggingNode: Node,
+    dropNode: Node,
+    dropType: Exclude<NodeDropType, 'none'>,
+    evt: DragEvent
+  ) => draggingNode && dropNode && evt,
+  'node-drag-leave': (draggingNode: Node, oldDropNode: Node, evt: DragEvent) =>
+    draggingNode && oldDropNode && evt,
+  'node-drag-enter': (draggingNode: Node, dropNode: Node, evt: DragEvent) =>
+    draggingNode && dropNode && evt,
+  'node-drag-over': (draggingNode: Node, dropNode: Node, evt: DragEvent) =>
+    draggingNode && dropNode && evt,
+}
+/* eslint-enable @typescript-eslint/no-unused-vars */
+
+export type TreeEmits = EmitFn<typeof treeEmits>
diff --git a/packages/components/tree/src/tree.type.ts b/packages/components/tree/src/tree.type.ts
index 3d67708ede..1ebf22a91a 100644
--- a/packages/components/tree/src/tree.type.ts
+++ b/packages/components/tree/src/tree.type.ts
@@ -8,9 +8,10 @@ import type {
 } from 'vue'
 import type Node from './model/node'
 import type TreeStore from './model/tree-store'
+import type { treeEmits } from './tree'
 
 export interface RootTreeType {
-  ctx: SetupContext<any>
+  ctx: SetupContext<typeof treeEmits>
   props: TreeComponentProps
   store: Ref<TreeStore>
   root: Ref<Node>
@@ -128,3 +129,10 @@ export interface TreeComponentProps {
 export type NodeDropType = 'before' | 'after' | 'inner' | 'none'
 
 export type { DragEvents } from './model/useDragNode'
+
+export interface CheckedInfo {
+  checkedKeys: TreeKey[]
+  checkedNodes: TreeData
+  halfCheckedKeys: TreeKey[]
+  halfCheckedNodes: TreeData
+}
diff --git a/packages/components/tree/src/tree.vue b/packages/components/tree/src/tree.vue
index c5161e98b5..4bb2037fb0 100644
--- a/packages/components/tree/src/tree.vue
+++ b/packages/components/tree/src/tree.vue
@@ -58,6 +58,7 @@ import { useDragNodeHandler } from './model/useDragNode'
 import { useKeydown } from './model/useKeydown'
 import { ROOT_TREE_INJECTION_KEY } from './tokens'
 import { isEqual } from 'lodash-unified'
+import { treeEmits } from './tree'
 
 import type Node from './model/node'
 import type { ComponentInternalInstance, PropType } from 'vue'
@@ -146,21 +147,7 @@ export default defineComponent({
       type: iconPropType,
     },
   },
-  emits: [
-    'check-change',
-    'current-change',
-    'node-click',
-    'node-contextmenu',
-    'node-collapse',
-    'node-expand',
-    'check',
-    'node-drag-start',
-    'node-drag-end',
-    'node-drop',
-    'node-drag-leave',
-    'node-drag-enter',
-    'node-drag-over',
-  ] as string[],
+  emits: treeEmits,
   setup(props, ctx) {
     const { t } = useLocale()
     const ns = useNamespace('tree')