Preserve partial creation replies on stream failure

src/components/platform-entry/usePlatformCreationAgentFlowController.test.tsx

@@ -0,0 +1,137 @@
+/* @vitest-environment jsdom */
+
+import { act, render, screen, waitFor } from '@testing-library/react';
+import { useEffect } from 'react';
+import { expect, test, vi } from 'vitest';
+
+import { usePlatformCreationAgentFlowController } from './usePlatformCreationAgentFlowController';
+
+type TestSession = {
+  sessionId: string;
+  messages: Array<{
+    id: string;
+    role: string;
+    kind?: string;
+    text: string;
+    createdAt?: string;
+  }>;
+};
+
+type TestMessagePayload = {
+  clientMessageId: string;
+  text: string;
+};
+
+function TestHarness({
+  streamMessage,
+}: {
+  streamMessage: (
+    sessionId: string,
+    payload: TestMessagePayload,
+    options?: { onUpdate?: (text: string) => void },
+  ) => Promise<TestSession>;
+}) {
+  const flow = usePlatformCreationAgentFlowController<
+    TestSession,
+    Record<string, never>,
+    { session: TestSession },
+    TestMessagePayload,
+    { action: string },
+    { session: TestSession }
+  >({
+    client: {
+      createSession: async () => ({
+        session: {
+          sessionId: 'session-1',
+          messages: [],
+        },
+      }),
+      getSession: async () => ({
+        session: {
+          sessionId: 'session-1',
+          messages: [],
+        },
+      }),
+      streamMessage,
+      executeAction: async () => ({
+        session: {
+          sessionId: 'session-1',
+          messages: [],
+        },
+      }),
+      selectSession: (response) => response.session,
+    },
+    createPayload: {},
+    workspaceStage: 'match3d-agent-workspace',
+    resultStage: 'match3d-result',
+    platformStage: 'platform',
+    isCompileAction: () => false,
+    resolveErrorMessage: (error, fallback) =>
+      error instanceof Error ? error.message : fallback,
+    errorMessages: {
+      open: '打开失败',
+      restoreMissingSession: '缺少会话',
+      restore: '恢复失败',
+      submit: '发送失败',
+      execute: '执行失败',
+    },
+    enterCreateTab: () => {},
+    setSelectionStage: () => {},
+  });
+
+  useEffect(() => {
+    void flow.openWorkspace({});
+  }, []);
+
+  return (
+    <div>
+      <button
+        type="button"
+        onClick={() => {
+          void flow.submitMessage({
+            clientMessageId: 'client-message-1',
+            text: '做一个办公室文具方洞挑战',
+          });
+        }}
+      >
+        发送
+      </button>
+      <div data-testid="messages">
+        {flow.session?.messages.map((message) => (
+          <div key={message.id}>{`${message.role}:${message.kind}:${message.text}`}</div>
+        ))}
+      </div>
+      {flow.error ? <div>{flow.error}</div> : null}
+    </div>
+  );
+}
+
+test('creation agent flow preserves streamed assistant text when stream fails', async () => {
+  const streamMessage = vi.fn(async (_sessionId, _payload, options) => {
+    options?.onUpdate?.('先把方洞万能的反差定住。');
+    throw new Error('方洞挑战聊天生成失败：LLM 请求超时');
+  });
+
+  render(<TestHarness streamMessage={streamMessage} />);
+
+  await waitFor(() => {
+    expect(screen.getByRole('button', { name: '发送' })).toBeTruthy();
+  });
+
+  await act(async () => {
+    screen.getByRole('button', { name: '发送' }).click();
+  });
+
+  await waitFor(() => {
+    expect(
+      screen.getByText('方洞挑战聊天生成失败：LLM 请求超时'),
+    ).toBeTruthy();
+  });
+
+  expect(screen.getByTestId('messages').textContent).toContain(
+    'user:chat:做一个办公室文具方洞挑战',
+  );
+  expect(screen.getByTestId('messages').textContent).toContain(
+    'assistant:warning:先把方洞万能的反差定住。',
+  );
+});