mock单测与libcmavsdk原生库脱钩

conftest新增fake_mavsdk fixture打桩mavsdk.offboard设定点类型,
两组网关测试autouse启用。修复树莓派原生库符号缺失时纯mock测试误失败
(该问题在树莓派实测暴露: 348条全绿不依赖mavsdk原生库)

utils/conftest.py

@@ -1,8 +1,46 @@
-"""pytest 根配置：保证无论从哪个工作目录启动 pytest，均可导入 utils/ 下的两个包。"""
+"""pytest 根配置：保证无论从哪个工作目录启动 pytest，均可导入 utils/ 下的包；
+并提供 fake_mavsdk fixture，使网关 mock 单测与真实 libcmavsdk.so 脱钩。"""
 
 import sys
+import types
 from pathlib import Path
 
+import pytest
+
 _UTILS_DIR = Path(__file__).resolve().parent
 if str(_UTILS_DIR) not in sys.path:
     sys.path.insert(0, str(_UTILS_DIR))
+
+
+@pytest.fixture
+def fake_mavsdk(monkeypatch):
+    """打桩 mavsdk.offboard 设定点类型(VelocityBodyYawspeed / VelocityNedYaw)。
+
+    MavsdkCommandGateway 构造设定点时惰性 `from mavsdk import offboard`——即便
+    offboard 传输层是 mock,也会去加载真实原生库。libcmavsdk.so 损坏或未装的
+    机器(如 libstdc++ 缺新符号的树莓派)上,纯 mock 单测会因此误失败。
+    用法与 fake_serial 打桩 pyserial 同理:sys.modules 注入轻量桩模块。
+    """
+    offboard_mod = types.ModuleType("mavsdk.offboard")
+
+    class VelocityBodyYawspeed:
+        def __init__(self, forward_m_s, right_m_s, down_m_s, yawspeed_deg_s):
+            self.forward_m_s = forward_m_s
+            self.right_m_s = right_m_s
+            self.down_m_s = down_m_s
+            self.yawspeed_deg_s = yawspeed_deg_s
+
+    class VelocityNedYaw:
+        def __init__(self, north_m_s, east_m_s, down_m_s, yaw_deg):
+            self.north_m_s = north_m_s
+            self.east_m_s = east_m_s
+            self.down_m_s = down_m_s
+            self.yaw_deg = yaw_deg
+
+    offboard_mod.VelocityBodyYawspeed = VelocityBodyYawspeed
+    offboard_mod.VelocityNedYaw = VelocityNedYaw
+    mavsdk_mod = types.ModuleType("mavsdk")
+    mavsdk_mod.offboard = offboard_mod
+    monkeypatch.setitem(sys.modules, "mavsdk", mavsdk_mod)
+    monkeypatch.setitem(sys.modules, "mavsdk.offboard", offboard_mod)
+    return offboard_mod