补充test_mql机械节点运动学

tests/test_test_mql_mechanical.py

@@ -63,6 +63,31 @@ class TestMqlMechanicalAssemblyTests(unittest.TestCase):
         for index, mass_state in enumerate(snapshot.states):
             self.assertAlmostEqual(rhs[2 * index + 1], mass_state.velocity_m_s)
 
+    def test_mechanical_mass_snapshot_exposes_lmechan1_node_kinematics(self) -> None:
+        closure = TestMqlMechanicalMassClosure(self.assembly)
+        state = closure.initial_state_vector()
+        state[16] = 0.2
+        state[17] = 0.37
+        state[18] = -0.3
+        state[19] = -0.72
+
+        snapshot = closure.snapshot(state)
+        front = snapshot.node_kinematics_by_alias[
+            "dynamic_mechanical_node_alternative_2"
+        ]
+        rear = snapshot.node_kinematics_by_alias[
+            "dynamic_mechanical_node_alternative_3"
+        ]
+
+        self.assertEqual(set(front.velocities_m_s), set(range(1, 9)))
+        self.assertEqual(set(front.displacements_m), set(range(1, 9)))
+        self.assertEqual(set(rear.velocities_m_s), set(range(1, 9)))
+        self.assertEqual(set(rear.displacements_m), set(range(1, 9)))
+        self.assertAlmostEqual(front.velocities_m_s[1], -0.2)
+        self.assertAlmostEqual(front.displacements_m[8], -0.37)
+        self.assertAlmostEqual(rear.velocities_m_s[1], -0.3)
+        self.assertAlmostEqual(rear.displacements_m[8], -0.72)
+
     def test_system_simulates_mechanical_mass_state_closure(self) -> None:
         system = TestMqlSystem()