fix: typing in ChatInput no longer causes unnecessary rerenders

This commit refactors the Chat component by removing unnecessary state management for input handling and streamlining the message submission process. The `setInput` state has been eliminated in favor of directly appending messages. Additionally, a new test suite for the ChatInput component has been introduced, covering rendering, message submission, and input behavior.

- Removed `input`, `handleInputChange`, and `handleSubmit` from Chat component.
- Updated message submission to use `append` directly.
- Added tests for ChatInput to ensure proper functionality and accessibility.

This refactor enhances code clarity and maintainability while ensuring the ChatInput component behaves as expected.

Author: nickytonline

src/components/Chat.tsx

@@ -824,12 +824,9 @@ export function Chat() {
 
   const {
     messages,
-    input,
-    handleInputChange,
-    handleSubmit,
     isLoading,
     setMessages,
-    setInput,
+    append,
   } = useChat({
     body: chatBody,
     onError: handleError,
@@ -883,10 +880,9 @@ export function Chat() {
           content: prompt,
         },
       ])
-
-      handleSubmit(new Event('submit'))
+      append({ role: 'user', content: prompt })
     },
-    [hasStartedChat, handleSubmit],
+    [hasStartedChat, append],
   )
 
   const handleServerToggle = useCallback((serverId: string) => {
@@ -907,15 +903,15 @@ export function Chat() {
     setStreaming(false)
     setTimedOut(false)
     setMessages([]) // Clear messages completely - initialMessage will be shown via renderEvents logic
-    setInput('')
+    // Removed: setInput('')
     setFocusTimestamp(Date.now())
     setUseCodeInterpreter(false)
     setUseWebSearch(false)
 
     textBufferRef.current = ''
     lastAssistantIdRef.current = null
     pendingStreamEventsRef.current = []
-  }, [setMessages, setInput])
+  }, [setMessages])
 
   const handleScrollToBottom = useCallback(() => {
     messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' })
@@ -1167,8 +1163,6 @@ export function Chat() {
         <ChatInput
           onSendMessage={handleSendMessage}
           disabled={isLoading || streaming}
-          value={input}
-          onChange={handleInputChange}
           focusTimestamp={focusTimestamp}
         />
       </div>

src/components/ChatInput.test.tsx

@@ -0,0 +1,58 @@
+import { describe, it, expect, vi } from 'vitest'
+import { render, screen, fireEvent } from '@testing-library/react'
+import { ChatInput } from './ChatInput'
+
+const setup = (props = {}) => {
+  const onSendMessage = vi.fn()
+  render(<ChatInput onSendMessage={onSendMessage} {...props} />)
+
+  const textarea = screen.getByRole('textbox', {
+    name: 'Ask something...',
+  }) as HTMLTextAreaElement
+  const { form } = textarea
+
+  return { onSendMessage, textarea, form }
+}
+
+describe('ChatInput', () => {
+  it('renders the input and button', () => {
+    setup()
+    expect(screen.getByPlaceholderText(/ask something/i)).toBeInTheDocument()
+    expect(screen.getByRole('button')).toBeInTheDocument()
+  })
+
+  it('submits message on Enter', () => {
+    const { onSendMessage, textarea } = setup()
+    fireEvent.change(textarea, { target: { value: 'Hello world' } })
+    fireEvent.keyDown(textarea, { key: 'Enter', code: 'Enter', charCode: 13 })
+    expect(onSendMessage).toHaveBeenCalledWith('Hello world')
+  })
+
+  it('does not submit on Shift+Enter', () => {
+    const { onSendMessage, textarea } = setup()
+    fireEvent.change(textarea, { target: { value: 'Hello\nworld' } })
+    fireEvent.keyDown(textarea, { key: 'Enter', code: 'Enter', shiftKey: true })
+    expect(onSendMessage).not.toHaveBeenCalled()
+  })
+
+  it('disables input and button when disabled', () => {
+    setup({ disabled: true })
+    expect(screen.getByPlaceholderText(/ask something/i)).toBeDisabled()
+    expect(screen.getByRole('button')).toBeDisabled()
+  })
+
+  it('autofocuses', () => {
+    const { textarea } = setup({ focusTimestamp: Date.now() })
+
+    expect(document.activeElement).toBe(textarea)
+  })
+
+  it('clears after submit', () => {
+    const { textarea } = setup()
+
+    fireEvent.change(textarea, { target: { value: 'Clear me' } })
+    fireEvent.keyDown(textarea, { key: 'Enter', code: 'Enter', charCode: 13 })
+
+    expect(textarea).toHaveValue('')
+  })
+})

src/components/ChatInput.tsx

@@ -1,21 +1,17 @@
-import React, { useRef, useEffect } from 'react'
+import { useRef, useEffect, type KeyboardEvent } from 'react'
 import { Button } from './ui/button'
 import { Send } from 'lucide-react'
 import { Textarea } from './ui/textarea'
 
 type ChatInputProps = {
   onSendMessage: (message: string) => void
   disabled?: boolean
-  value: string
-  onChange: (e: React.ChangeEvent<HTMLTextAreaElement>) => void
   focusTimestamp?: number
 }
 
 export function ChatInput({
   onSendMessage,
   disabled = false,
-  value,
-  onChange,
   focusTimestamp,
 }: ChatInputProps) {
   const textareaRef = useRef<HTMLTextAreaElement>(null)
@@ -28,31 +24,28 @@ export function ChatInput({
 
   useEffect(() => {
     if (textareaRef.current) {
-      // Reset height to calculate the right one
       textareaRef.current.style.height = 'auto'
-      // Set new height based on scrollHeight (content)
       textareaRef.current.style.height = `${Math.min(textareaRef.current.scrollHeight, 128)}px`
     }
-  }, [value])
+  }, [textareaRef.current?.value])
 
-  const handleSubmit = (e: React.FormEvent) => {
+  const handleSubmit = (e: React.FormEvent<HTMLFormElement>) => {
     e.preventDefault()
+    const form = e.currentTarget as HTMLFormElement
+    const textarea = form.elements.namedItem('prompt') as HTMLTextAreaElement
+    const { value } = textarea
 
     if (value.trim() && !disabled) {
       onSendMessage(value)
-
-      // Reset the textarea height
-      if (textareaRef.current) {
-        textareaRef.current.style.height = 'auto'
-      }
+      form.reset()
+      textarea.style.height = 'auto'
     }
   }
 
-  const handleKeyDown = (e: React.KeyboardEvent) => {
-    // Submit on Enter without Shift
+  const handleKeyDown = (e: KeyboardEvent<HTMLTextAreaElement>) => {
     if (e.key === 'Enter' && !e.shiftKey) {
       e.preventDefault()
-      handleSubmit(e)
+      e.currentTarget.form?.requestSubmit()
     }
   }
 
@@ -64,22 +57,23 @@ export function ChatInput({
       <div className="relative flex-1 flex items-center">
         <Textarea
           ref={textareaRef}
-          value={value}
-          onChange={onChange}
+          name="prompt"
           onKeyDown={handleKeyDown}
           placeholder="Ask something..."
           required
           disabled={disabled}
           rows={1}
+          aria-label="Ask something..."
           className="w-full resize-none rounded-lg border-0 pr-12 text-base placeholder:text-gray-500 focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:focus:ring-indigo-400 disabled:opacity-50 transition-all"
         />
         <Button
           type="submit"
           variant="default"
           className="absolute right-2 size-8"
-          aria-label="Send message"
+          disabled={disabled}
         >
-          <Send className="size-4" />
+          <span className="sr-only">Send message</span>
+          <Send className="size-4" aria-hidden="true" />
         </Button>
       </div>
     </form>