Add nonlinear matrix free test

test/nonlinear/CMakeLists.txt

@@ -9,6 +9,12 @@ dune_add_formcompiler_system_test(UFLFILE nonlinear_dg.ufl
                                   INIFILE nonlinear_dg.mini
                                   )
 
+dune_add_formcompiler_system_test(UFLFILE nonlinear.ufl
+                                  BASENAME nonlinear_matrix_free
+                                  INIFILE nonlinear_matrix_free.mini
+                                  )
+
+
 # Add the reference code with the PDELab localoperator that produced
 # the reference vtk file
 add_executable(nonlinear_ref reference_main.cc)

test/nonlinear/nonlinear_matrix_free.mini

+__name = nonlinear_matrix_free_{__exec_suffix}
+__exec_suffix = numdiff, symdiff | expand num
+
+lowerleft = 0.0 0.0
+upperright = 1.0 1.0
+elements = 32 32
+elementType = simplical
+
+[wrapper.vtkcompare]
+name = {__name}
+extension = vtu
+
+[formcompiler]
+numerical_jacobian = 1, 0 | expand num
+matrix_free = 1
+exact_solution_expression = g
+compare_l2errorsquared = 1e-3