fix: 兼容插件仪表盘空返回

tests/test_plugin_dashboard.py

@@ -0,0 +1,65 @@
+from types import SimpleNamespace
+from typing import Any, Iterator
+
+import pytest
+from fastapi import HTTPException
+
+from app.core.plugin import PluginManager
+from app.utils.singleton import Singleton
+
+
+@pytest.fixture
+def plugin_manager() -> Iterator[PluginManager]:
+    """构造隔离的插件管理器实例，避免单例状态污染其它用例。"""
+    Singleton._instances.pop((PluginManager, (), frozenset()), None)
+    manager = PluginManager()
+    yield manager
+    Singleton._instances.pop((PluginManager, (), frozenset()), None)
+
+
+def _plugin_with_dashboard(dashboard: Any) -> SimpleNamespace:
+    """构造仅包含仪表板接口的插件实例。"""
+    return SimpleNamespace(
+        plugin_name="演示插件",
+        get_render_mode=lambda: ("vue", "dist/assets"),
+        get_dashboard=lambda key=None, user_agent=None: dashboard,
+    )
+
+
+def test_plugin_dashboard_keeps_vue_elements_none(plugin_manager: PluginManager) -> None:
+    """Vue 仪表板的 elements=None 应原样返回给前端渲染远程组件。"""
+    plugin_manager.running_plugins["DemoPlugin"] = _plugin_with_dashboard(
+        (
+            {"cols": 12},
+            {"title": "演示插件", "border": True},
+            None,
+        )
+    )
+
+    dashboard = plugin_manager.get_plugin_dashboard("DemoPlugin", "usage")
+
+    assert dashboard.id == "DemoPlugin"
+    assert dashboard.render_mode == "vue"
+    assert dashboard.cols == {"cols": 12}
+    assert dashboard.attrs == {"title": "演示插件", "border": True}
+    assert dashboard.elements is None
+
+
+def test_plugin_dashboard_returns_none_when_plugin_has_no_dashboard(plugin_manager: PluginManager) -> None:
+    """插件声明当前无仪表板时应返回 None，而不是触发解包异常。"""
+    plugin_manager.running_plugins["DemoPlugin"] = _plugin_with_dashboard(None)
+
+    assert plugin_manager.get_plugin_dashboard("DemoPlugin", "missing") is None
+
+
+def test_plugin_dashboard_rejects_invalid_dashboard_shape(plugin_manager: PluginManager) -> None:
+    """非空但不符合三元组契约的仪表板数据应返回服务端错误。"""
+    plugin_manager.running_plugins["DemoPlugin"] = _plugin_with_dashboard(
+        {"cols": {}, "attrs": {}, "elements": []}
+    )
+
+    with pytest.raises(HTTPException) as exc_info:
+        plugin_manager.get_plugin_dashboard("DemoPlugin", "broken")
+
+    assert exc_info.value.status_code == 500
+    assert "仪表盘数据格式错误" in exc_info.value.detail