fix streaming

server/tests/chat-tools-streaming.test.ts

@@ -0,0 +1,107 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import {
+  runToolAwareChatCompletionsStream,
+  runToolAwareOpenAIChatStream,
+  type ToolAwareStreamingEvent,
+} from "../src/llm/chat-tools.js";
+
+async function* streamFrom(events: any[]) {
+  for (const event of events) {
+    await Promise.resolve();
+    yield event;
+  }
+}
+
+async function collectEvents(iterable: AsyncIterable<ToolAwareStreamingEvent>) {
+  const events: ToolAwareStreamingEvent[] = [];
+  for await (const event of iterable) {
+    events.push(event);
+  }
+  return events;
+}
+
+test("OpenAI Responses stream emits text deltas as they arrive", async () => {
+  const outputMessage = {
+    id: "msg_1",
+    type: "message",
+    role: "assistant",
+    status: "completed",
+    content: [{ type: "output_text", text: "Hello" }],
+  };
+  const client = {
+    responses: {
+      create: async () =>
+        streamFrom([
+          { type: "response.output_item.added", item: { ...outputMessage, content: [] }, output_index: 0 },
+          { type: "response.output_text.delta", delta: "Hel", output_index: 0, content_index: 0 },
+          { type: "response.output_text.delta", delta: "lo", output_index: 0, content_index: 0 },
+          { type: "response.output_item.done", item: outputMessage, output_index: 0 },
+          {
+            type: "response.completed",
+            response: {
+              status: "completed",
+              output_text: "Hello",
+              output: [outputMessage],
+              usage: { input_tokens: 2, output_tokens: 1, total_tokens: 3 },
+            },
+          },
+        ]),
+    },
+  };
+
+  const events = await collectEvents(
+    runToolAwareOpenAIChatStream({
+      client: client as any,
+      model: "gpt-test",
+      messages: [{ role: "user", content: "Say hello" }],
+    })
+  );
+
+  assert.deepEqual(
+    events.map((event) => event.type),
+    ["delta", "delta", "done"]
+  );
+  assert.deepEqual(
+    events.filter((event) => event.type === "delta").map((event) => event.text),
+    ["Hel", "lo"]
+  );
+  assert.equal(events.at(-1)?.type === "done" ? events.at(-1)?.result.text : null, "Hello");
+});
+
+test("OpenAI-compatible Chat Completions stream emits text deltas as they arrive", async () => {
+  const client = {
+    chat: {
+      completions: {
+        create: async () =>
+          streamFrom([
+            { choices: [{ delta: { role: "assistant" } }] },
+            { choices: [{ delta: { content: "Hel" } }] },
+            { choices: [{ delta: { content: "lo" } }] },
+            {
+              choices: [{ delta: {}, finish_reason: "stop" }],
+              usage: { prompt_tokens: 2, completion_tokens: 1, total_tokens: 3 },
+            },
+          ]),
+      },
+    },
+  };
+
+  const events = await collectEvents(
+    runToolAwareChatCompletionsStream({
+      client: client as any,
+      model: "grok-test",
+      messages: [{ role: "user", content: "Say hello" }],
+    })
+  );
+
+  assert.deepEqual(
+    events.map((event) => event.type),
+    ["delta", "delta", "done"]
+  );
+  assert.deepEqual(
+    events.filter((event) => event.type === "delta").map((event) => event.text),
+    ["Hel", "lo"]
+  );
+  assert.equal(events.at(-1)?.type === "done" ? events.at(-1)?.result.text : null, "Hello");
+});