[CI] Ensure 1D lambda is constant

Also, add contributor

AUTHORS

@@ -67,5 +67,6 @@ Anthony Walker (@anthony-walker), Oregon State University
 Bryan Weber (@bryanwweber), University of Connecticut
 Armin Wehrfritz (@awehrfritz)
 Richard West (@rwest), Northeastern University
+Shumeng Xie (@yeanment), National University of Singapore
 Chao Xu (@12Chao), Northeastern University
 Thorsten Zirwes (@g3bk47), Karlsruhe Institute of Technology

test/python/test_onedim.py

@@ -1282,6 +1282,7 @@ def run_case(self, phi, T, width, P):
         sim.solve(loglevel=0, auto=True)
         self.assertTrue(all(sim.T >= T - 1e-3))
         self.assertTrue(all(sim.spread_rate >= -1e-9))
+        assert np.allclose(sim.L, sim.L[0])
         return sim
 
     @utilities.slow_test
@@ -1391,6 +1392,7 @@ def run_case(self, phi, T, width, P):
         sim.solve(loglevel=0, auto=True)
         self.assertTrue(all(sim.T >= T - 1e-3))
         self.assertTrue(all(sim.spread_rate >= -1e-9))
+        assert np.allclose(sim.L, sim.L[0])
         return sim
 
     @utilities.slow_test
@@ -1436,6 +1438,7 @@ def solve(self, phi, T, width, P):
         sim.burner.mdot = gas.density * 0.15
         sim.solve(loglevel=0, auto=True)
         self.assertGreater(sim.T[1], T)
+        assert np.allclose(sim.L, 0)
 
     def test_case1(self):
         self.solve(phi=0.5, T=500, width=2.0, P=0.1)
@@ -1530,6 +1533,7 @@ def run_stagnation(self, xh2, mdot, width):
         sim.solve(loglevel=0, auto=True)
 
         assert sim.T.max() > tburner + tsurf
+        assert np.allclose(sim.L, sim.L[0])
         self.sim = sim
 
     def test_stagnation_case1(self):
@@ -1717,6 +1721,7 @@ def solve(self, phi, T, width, P):
         sim.reactants.mdot = gas.density * axial_velocity
         sim.solve(loglevel=0, auto=True)
         self.assertGreater(sim.T[-1], T + 100)
+        assert np.allclose(sim.L, sim.L[0])
         return sim
 
     def test_restart(self):