feat: added test for invalid material

tests/test_erosion.py

@@ -325,14 +325,19 @@ def test_F(a_rad, angle_dependency, E):
  F(a_rad, angle_dependency)
 
 
-# Material properties function #
+# Material properties function 
 material_validation = [('carbon_steel', (7800, 2e-9, 2.6, 'ductile')),
  ('grp_epoxy', (1800, 3e-10, 3.6, 'ductile')),
  ('psz_ceramic_zirconia', (5700, 4.1e-9, 2.5, 'brittle'))]
 @pytest.mark.parametrize('material, E', material_validation)
 def test_get_material_properties(material, E):
  assert get_material_properties(material) == E
 
+
+def test_get_material_properties_invalid_material():
+ with pytest.raises(exc.FunctionInputFail):
+ get_material_properties(material='invalid material')
+
 # Test material list and error raising
 def test_get_materials():
  material_list = ['carbon_steel', 'duplex', 'ss316', 'inconel', 'grp_epoxy', 'grp_vinyl_ester', 'hdpe', 'aluminium',
@@ -341,6 +346,7 @@ def test_get_materials():
  'TiB2_titanium_diboride', 'B4C_boron_carbide', 'SiSiC_ceramic_carbide']
  assert get_materials() == material_list
 
+
 def test_return_nan():
  v_m = 29.3
  rho_m = 30