fix: timeout error no longer appears after tool call fail or new chat (#131)

This pull request introduces enhancements to the chat functionality and
streaming logic to improve error handling and streamline event
signaling. The most important changes include adding a reset for the
`timedOut` state in the chat component, centralizing the `stream_done`
event chunk, and ensuring the `stream_done` event is emitted even when
errors occur during streaming.

Relates to #127

<img width="3692" height="1560" alt="CleanShot 2025-07-11 at 10 23
10@2x"
src="https://github.com/user-attachments/assets/f81d438f-3e5e-4c30-979e-7b8d83852fb7"
/>

Author: nickytonline

src/components/Chat.tsx

@@ -905,6 +905,7 @@ export function Chat() {
     setHasStartedChat(false)
     setStreamBuffer([])
     setStreaming(false)
+    setTimedOut(false)
     setMessages([]) // Clear messages completely - initialMessage will be shown via renderEvents logic
     setInput('')
     setFocusTimestamp(Date.now())

src/lib/streaming.test.ts

@@ -143,4 +143,26 @@ describe('streamText', () => {
     // Should include t:{...stream_done...}
     expect(result).toMatch(/t:{\"type\":\"stream_done\"}/)
   })
+
+  it('emits stream_done when an error occurs', async () => {
+    // Simulate an error thrown during streaming
+    const errorIterable = {
+      async *[Symbol.asyncIterator]() {
+        throw new Error('Simulated streaming error')
+      },
+    }
+    const response = streamText(errorIterable)
+    const reader = response.body!.getReader()
+    let result = ''
+    let done = false
+    while (!done) {
+      const { value, done: d } = await reader.read()
+      if (value) result += new TextDecoder().decode(value)
+      done = d
+    }
+    // Should include t:{...stream_done...} even on error
+    expect(result).toMatch(/t:{"type":"stream_done"}/)
+    // Should also include the error event
+    expect(result).toMatch(/e:{"type":"error".*}/)
+  })
 })

src/lib/streaming.ts

@@ -1,5 +1,10 @@
 import { APIError } from 'openai'
 
+// Event chunk for stream completion
+const STREAM_DONE_CHUNK = new TextEncoder().encode(
+  `t:${JSON.stringify({ type: 'stream_done' })}\n`,
+)
+
 export function streamText(
   answer: AsyncIterable<any>,
   onMessageId?: (messageId: string) => void,
@@ -358,9 +363,7 @@ export function streamText(
         // Flush any remaining content
         flush()
         // Emit a final done event to signal successful completion
-        controller.enqueue(
-          encoder.encode(`t:${JSON.stringify({ type: 'stream_done' })}\n`),
-        )
+        controller.enqueue(STREAM_DONE_CHUNK)
         controller.close()
       } catch (error: unknown) {
         console.error('Error during streamed response:', error)
@@ -385,6 +388,9 @@ export function streamText(
           ),
         )
 
+        // Always emit stream_done after error
+        controller.enqueue(STREAM_DONE_CHUNK)
+
         // Close the stream
         try {
           controller.close()