added a test that adds a unused variable to the petsc options

test/system_tests/test_misc.py

@@ -0,0 +1,39 @@
+import dolfinx
+import festim as F
+import numpy as np
+
+
+def test_petsc_options():
+    my_model = F.HydrogenTransportProblem(
+        petsc_options={
+            "ksp_type": "preonly",
+            "pc_type": "lu",
+            "pc_factor_mat_solver_type": "mumps",
+            "coucoucou": 3,
+        }
+    )
+
+    tungsten = F.Material(D_0=1, E_D=0, K_S_0=1, E_K_S=0)
+
+    my_model.mesh = F.Mesh1D(vertices=np.linspace(0, 1, num=100))
+    vol1 = F.VolumeSubdomain1D(id=1, material=tungsten, borders=[0, 1])
+    surface1 = F.SurfaceSubdomain1D(id=4, x=0)
+    surface2 = F.SurfaceSubdomain1D(id=5, x=1)
+
+    my_model.subdomains = [vol1, surface1, surface2]
+
+    mobile = F.Species(name="H", mobile=True)
+
+    my_model.species = [mobile]
+
+    my_model.temperature = 600
+
+    my_model.boundary_conditions = [
+        F.FixedConcentrationBC(subdomain=surface1, species=mobile, value=1),
+        F.FixedConcentrationBC(subdomain=surface2, species=mobile, value=0),
+    ]
+
+    my_model.settings = F.Settings(atol=1e-6, rtol=1e-6, transient=False)
+
+    my_model.initialise()
+    my_model.run()