Enable real guest networking and make demos network-first

tests/test_vm_guest.py

@@ -8,9 +8,13 @@ from pyro_mcp.vm_guest import VsockExecClient
 
 
 class StubSocket:
-    def __init__(self, response: bytes) -> None:
-        self.response = response
-        self.connected: tuple[int, int] | None = None
+    def __init__(self, responses: list[bytes] | bytes) -> None:
+        if isinstance(responses, bytes):
+            self.responses = [responses]
+        else:
+            self.responses = responses
+        self._buffer = b""
+        self.connected: object | None = None
         self.sent = b""
         self.timeout: int | None = None
         self.closed = False
@@ -25,10 +29,12 @@ class StubSocket:
         self.sent += data
 
     def recv(self, size: int) -> bytes:
-        del size
-        if self.response == b"":
+        if not self._buffer and self.responses:
+            self._buffer = self.responses.pop(0)
+        if not self._buffer:
             return b""
-        data, self.response = self.response, b""
+        data = self._buffer[:size]
+        self._buffer = self._buffer[size:]
         return data
 
     def close(self) -> None:
@@ -62,3 +68,36 @@ def test_vsock_exec_client_rejects_bad_json(monkeypatch: pytest.MonkeyPatch) ->
     client = VsockExecClient(socket_factory=lambda family, sock_type: stub)
     with pytest.raises(RuntimeError, match="JSON object"):
         client.exec(1234, 5005, "echo ok", 30)
+
+
+def test_vsock_exec_client_uses_unix_bridge_when_vsock_is_unavailable(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.delattr(socket, "AF_VSOCK", raising=False)
+    stub = StubSocket(
+        [
+            b"OK 1073746829\n",
+            b'{"stdout":"ready\\n","stderr":"","exit_code":0,"duration_ms":5}',
+        ]
+    )
+
+    def socket_factory(family: int, sock_type: int) -> StubSocket:
+        assert family == socket.AF_UNIX
+        assert sock_type == socket.SOCK_STREAM
+        return stub
+
+    client = VsockExecClient(socket_factory=socket_factory)
+    response = client.exec(1234, 5005, "echo ready", 30, uds_path="/tmp/vsock.sock")
+
+    assert response.stdout == "ready\n"
+    assert stub.connected == "/tmp/vsock.sock"
+    assert stub.sent.startswith(b"CONNECT 5005\n")
+
+
+def test_vsock_exec_client_requires_transport_when_vsock_is_unavailable(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.delattr(socket, "AF_VSOCK", raising=False)
+    client = VsockExecClient(socket_factory=lambda family, sock_type: StubSocket(b""))
+    with pytest.raises(RuntimeError, match="not supported"):
+        client.exec(1234, 5005, "echo ok", 30)