From 23a89406d81afe8434094cbfb8a66c43c86b2bfb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=BA=8C=E8=B4=A7=E6=9C=BA=E5=99=A8=E4=BA=BA?=
 <smith3816@gmail.com>
Date: Mon, 10 Nov 2025 16:56:33 +0800
Subject: [PATCH] feat: triggerFocus support

---
 src/Dom/focus.ts    | 40 ++++++++++++++++++++++++++++++++++++++++
 tests/focus.test.ts | 27 ++++++++++++++++++++++++++-
 2 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/src/Dom/focus.ts b/src/Dom/focus.ts
index a6654841..6b182463 100644
--- a/src/Dom/focus.ts
+++ b/src/Dom/focus.ts
@@ -97,3 +97,43 @@ export function limitTabRange(node: HTMLElement, e: KeyboardEvent) {
     }
   }
 }
+
+export interface InputFocusOptions extends FocusOptions {
+  cursor?: 'start' | 'end' | 'all';
+}
+
+// Used for `rc-input` `rc-textarea` `rc-input-number`
+/**
+ * Focus element and set cursor position for input/textarea elements.
+ */
+export function triggerFocus(
+  element?: HTMLElement,
+  option?: InputFocusOptions,
+) {
+  if (!element) return;
+
+  element.focus(option);
+
+  // Selection content
+  const { cursor } = option || {};
+  if (
+    cursor &&
+    (element instanceof HTMLInputElement ||
+      element instanceof HTMLTextAreaElement)
+  ) {
+    const len = element.value.length;
+
+    switch (cursor) {
+      case 'start':
+        element.setSelectionRange(0, 0);
+        break;
+
+      case 'end':
+        element.setSelectionRange(len, len);
+        break;
+
+      default:
+        element.setSelectionRange(0, len);
+    }
+  }
+}
diff --git a/tests/focus.test.ts b/tests/focus.test.ts
index 795e2e71..1c835bf9 100644
--- a/tests/focus.test.ts
+++ b/tests/focus.test.ts
@@ -1,6 +1,6 @@
 /* eslint-disable class-methods-use-this */
 import { spyElementPrototype } from '../src/test/domHook';
-import { getFocusNodeList } from '../src/Dom/focus';
+import { getFocusNodeList, triggerFocus } from '../src/Dom/focus';
 
 describe('focus', () => {
   beforeAll(() => {
@@ -31,4 +31,29 @@ describe('focus', () => {
     const tabFocusList = getFocusNodeList(div, true);
     expect(tabFocusList).toHaveLength(5);
   });
+
+  it('triggerFocus should set cursor position for textarea', () => {
+    const textarea = document.createElement('textarea');
+    textarea.value = 'test content';
+
+    const focusSpy = jest.spyOn(textarea, 'focus');
+    const setSelectionRangeSpy = jest.spyOn(textarea, 'setSelectionRange');
+
+    // Test cursor: 'start'
+    triggerFocus(textarea, { cursor: 'start' });
+    expect(setSelectionRangeSpy).toHaveBeenCalledWith(0, 0);
+
+    // Test cursor: 'end'
+    triggerFocus(textarea, { cursor: 'end' });
+    expect(setSelectionRangeSpy).toHaveBeenCalledWith(12, 12); // 'test content'.length = 12
+
+    // Test cursor: 'all'
+    triggerFocus(textarea, { cursor: 'all' });
+    expect(setSelectionRangeSpy).toHaveBeenCalledWith(0, 12); // select all text
+
+    expect(focusSpy).toHaveBeenCalledTimes(3);
+
+    focusSpy.mockRestore();
+    setSelectionRangeSpy.mockRestore();
+  });
 });