added test for iterate

test/test_h_transport_problem.py

@@ -0,0 +1,58 @@
+import festim as F
+import tqdm.autonotebook
+import mpi4py.MPI as MPI
+import dolfinx
+import ufl
+import numpy as np
+
+# TODO test all the methods in the class
+
+
+def test_iterate():
+    """Test that the iterate method updates the solution and time correctly"""
+    # BUILD
+    my_model = F.HydrogenTransportProblem()
+
+    my_model.settings = F.Settings(atol=1e-6, rtol=1e-6, final_time=10)
+
+    my_model.progress = tqdm.autonotebook.tqdm(
+        desc="Solving H transport problem",
+        total=my_model.settings.final_time,
+        unit_scale=True,
+    )
+
+    my_model.boundary_conditions = []
+
+    mesh = dolfinx.mesh.create_unit_square(MPI.COMM_WORLD, 10, 10)
+
+    V = dolfinx.fem.FunctionSpace(mesh, ("CG", 1))
+    my_model.u = dolfinx.fem.Function(V)
+    my_model.u_n = dolfinx.fem.Function(V)
+    my_model.dt = dolfinx.fem.Constant(mesh, 2.0)
+    v = ufl.TestFunction(V)
+
+    source_value = 2.0
+    form = (
+        my_model.u - my_model.u_n
+    ) / my_model.dt * v * ufl.dx - source_value * v * ufl.dx
+
+    problem = dolfinx.fem.petsc.NonlinearProblem(form, my_model.u, bcs=[])
+    my_model.solver = dolfinx.nls.petsc.NewtonSolver(MPI.COMM_WORLD, problem)
+
+    my_model.t = dolfinx.fem.Constant(mesh, 0.0)
+
+    for i in range(10):
+        # RUN
+        my_model.iterate(skip_post_processing=True)
+
+        # TEST
+
+        # check that t evolves
+        expected_t_value = (i + 1) * float(my_model.dt)
+        assert np.isclose(float(my_model.t), expected_t_value)
+
+        # check that u and u_n are updated
+        expected_u_value = (i + 1) * float(my_model.dt) * source_value
+        assert np.all(np.isclose(my_model.u.x.array, expected_u_value))
+
+        assert np.all(np.isclose(my_model.u_n.x.array, expected_u_value))