fix(telegram): stream replies in-place without duplicate final sends

src/telegram/draft-stream.test.ts

@@ -2,52 +2,117 @@ import { describe, expect, it, vi } from "vitest";
 import { createTelegramDraftStream } from "./draft-stream.js";
 
 describe("createTelegramDraftStream", () => {
-  it("passes message_thread_id when provided", () => {
-    const api = { sendMessageDraft: vi.fn().mockResolvedValue(true) };
+  it("sends stream preview message with message_thread_id when provided", async () => {
+    const api = {
+      sendMessage: vi.fn().mockResolvedValue({ message_id: 17 }),
+      editMessageText: vi.fn().mockResolvedValue(true),
+      deleteMessage: vi.fn().mockResolvedValue(true),
+    };
     const stream = createTelegramDraftStream({
       // oxlint-disable-next-line typescript/no-explicit-any
       api: api as any,
       chatId: 123,
-      draftId: 42,
       thread: { id: 99, scope: "forum" },
     });
 
     stream.update("Hello");
 
-    expect(api.sendMessageDraft).toHaveBeenCalledWith(123, 42, "Hello", {
-      message_thread_id: 99,
-    });
+    await vi.waitFor(() =>
+      expect(api.sendMessage).toHaveBeenCalledWith(123, "Hello", { message_thread_id: 99 }),
+    );
   });
 
-  it("omits message_thread_id for general topic id", () => {
-    const api = { sendMessageDraft: vi.fn().mockResolvedValue(true) };
+  it("edits existing stream preview message on subsequent updates", async () => {
+    const api = {
+      sendMessage: vi.fn().mockResolvedValue({ message_id: 17 }),
+      editMessageText: vi.fn().mockResolvedValue(true),
+      deleteMessage: vi.fn().mockResolvedValue(true),
+    };
+    const stream = createTelegramDraftStream({
+      // oxlint-disable-next-line typescript/no-explicit-any
+      api: api as any,
+      chatId: 123,
+      thread: { id: 99, scope: "forum" },
+    });
+
+    stream.update("Hello");
+    await vi.waitFor(() =>
+      expect(api.sendMessage).toHaveBeenCalledWith(123, "Hello", { message_thread_id: 99 }),
+    );
+    await (api.sendMessage.mock.results[0]?.value as Promise<unknown>);
+
+    stream.update("Hello again");
+    await stream.flush();
+
+    expect(api.editMessageText).toHaveBeenCalledWith(123, 17, "Hello again");
+  });
+
+  it("waits for in-flight updates before final flush edit", async () => {
+    let resolveSend: ((value: { message_id: number }) => void) | undefined;
+    const firstSend = new Promise<{ message_id: number }>((resolve) => {
+      resolveSend = resolve;
+    });
+    const api = {
+      sendMessage: vi.fn().mockReturnValue(firstSend),
+      editMessageText: vi.fn().mockResolvedValue(true),
+      deleteMessage: vi.fn().mockResolvedValue(true),
+    };
+    const stream = createTelegramDraftStream({
+      // oxlint-disable-next-line typescript/no-explicit-any
+      api: api as any,
+      chatId: 123,
+      thread: { id: 99, scope: "forum" },
+    });
+
+    stream.update("Hello");
+    await vi.waitFor(() => expect(api.sendMessage).toHaveBeenCalledTimes(1));
+    stream.update("Hello final");
+    const flushPromise = stream.flush();
+    expect(api.editMessageText).not.toHaveBeenCalled();
+
+    resolveSend?.({ message_id: 17 });
+    await flushPromise;
+
+    expect(api.editMessageText).toHaveBeenCalledWith(123, 17, "Hello final");
+  });
+
+  it("omits message_thread_id for general topic id", async () => {
+    const api = {
+      sendMessage: vi.fn().mockResolvedValue({ message_id: 17 }),
+      editMessageText: vi.fn().mockResolvedValue(true),
+      deleteMessage: vi.fn().mockResolvedValue(true),
+    };
     const stream = createTelegramDraftStream({
       // oxlint-disable-next-line typescript/no-explicit-any
       api: api as any,
       chatId: 123,
-      draftId: 42,
       thread: { id: 1, scope: "forum" },
     });
 
     stream.update("Hello");
 
-    expect(api.sendMessageDraft).toHaveBeenCalledWith(123, 42, "Hello", undefined);
+    await vi.waitFor(() => expect(api.sendMessage).toHaveBeenCalledWith(123, "Hello", undefined));
   });
 
-  it("keeps message_thread_id for dm threads", () => {
-    const api = { sendMessageDraft: vi.fn().mockResolvedValue(true) };
+  it("keeps message_thread_id for dm threads and clears preview on cleanup", async () => {
+    const api = {
+      sendMessage: vi.fn().mockResolvedValue({ message_id: 17 }),
+      editMessageText: vi.fn().mockResolvedValue(true),
+      deleteMessage: vi.fn().mockResolvedValue(true),
+    };
     const stream = createTelegramDraftStream({
       // oxlint-disable-next-line typescript/no-explicit-any
       api: api as any,
       chatId: 123,
-      draftId: 42,
       thread: { id: 1, scope: "dm" },
     });
 
     stream.update("Hello");
+    await vi.waitFor(() =>
+      expect(api.sendMessage).toHaveBeenCalledWith(123, "Hello", { message_thread_id: 1 }),
+    );
+    await stream.clear();
 
-    expect(api.sendMessageDraft).toHaveBeenCalledWith(123, 42, "Hello", {
-      message_thread_id: 1,
-    });
+    expect(api.deleteMessage).toHaveBeenCalledWith(123, 17);
   });
 });