feat: stream provider responses

tests/unit/test_cli.py

@@ -19,6 +19,22 @@ class _FakeProvider:
     def chat(self, messages: list[ChatMessage]) -> str:
         return f"Echo: {messages[-1].content}"
 
+    def stream_chat(self, messages: list[ChatMessage]):
+        yield "Echo: "
+        yield messages[-1].content
+
+
+class _MarkdownProvider(_FakeProvider):
+    def stream_chat(self, messages: list[ChatMessage]):
+        yield "## **Ant"
+        yield "wort**\n`SQLite`"
+
+
+class _InterruptingProvider(_FakeProvider):
+    def stream_chat(self, messages: list[ChatMessage]):
+        yield "angefangene Antwort"
+        raise KeyboardInterrupt
+
 
 class _FakeHybridProvider(_FakeProvider):
     name = "hybrid"
@@ -59,10 +75,53 @@ class CliTests(unittest.TestCase):
             )
 
         self.assertEqual(result, 0)
-        self.assertTrue(any(line == "Javis: Echo: Hallo" for line in output))
+        self.assertIn("Javis: Echo: Hallo\n", "".join(output))
         self.assertTrue(any("Nachrichten" in line for line in output))
         self.assertEqual(output[-1], "Chat beendet.")
 
+    def test_streaming_cleans_terminal_markdown_but_persists_raw_answer(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            store = SQLiteSessionStore(Path(directory) / "sessions.sqlite3")
+            service = ChatService(store, _MarkdownProvider())
+            inputs = iter(["Frage", "/exit"])
+            output: list[str] = []
+            streamed: list[str] = []
+
+            result = run_chat(
+                service,
+                input_fn=lambda _prompt: next(inputs),
+                output=output.append,
+                stream_output=streamed.append,
+            )
+            session = service.list_sessions()[0]
+            messages = service.load_session(session.id).messages
+
+        self.assertEqual(result, 0)
+        self.assertEqual("".join(streamed), "Javis: Antwort\nSQLite\n")
+        self.assertEqual(messages[-1].content, "## **Antwort**\n`SQLite`")
+
+    def test_keyboard_interrupt_drops_partial_answer_and_returns_to_prompt(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            store = SQLiteSessionStore(Path(directory) / "sessions.sqlite3")
+            service = ChatService(store, _InterruptingProvider())
+            inputs = iter(["Frage", "/exit"])
+            output: list[str] = []
+            streamed: list[str] = []
+
+            result = run_chat(
+                service,
+                input_fn=lambda _prompt: next(inputs),
+                output=output.append,
+                stream_output=streamed.append,
+            )
+            session = service.list_sessions()[0]
+            messages = service.load_session(session.id).messages
+
+        self.assertEqual(result, 0)
+        self.assertEqual(messages, [])
+        self.assertTrue(any("nicht gespeichert" in line for line in output))
+        self.assertEqual(output[-1], "Chat beendet.")
+
     def test_provider_privacy_and_status_commands_are_sanitized(self) -> None:
         with tempfile.TemporaryDirectory() as directory:
             store = SQLiteSessionStore(Path(directory) / "sessions.sqlite3")