Replace how .load is called

https://marshmallow.readthedocs.io/en/stable/upgrading.html#schemas-are-always-strict

`.load` doesn't return a `(data, errors)` tuple any more - only data is
returned. A `ValidationError` is raised if validation fails. The code
now relies on the `marshmallow_validation_error` error handler to handle
errors instead of having to raise an `InvalidRequest`. This has no
effect on the response that is returned (a test has been modified to
check).

Also added a new `password` field to the `UserSchema` so that we don't
have to specially check for password errors in the `.create_user` endpoint
- we can let marshmallow handle them.

tests/app/test_schemas.py

@@ -64,7 +64,7 @@ def test_user_update_schema_accepts_valid_attribute_pairs(user_attribute, user_v
     }
     from app.schemas import user_update_schema_load_json
 
-    data, errors = user_update_schema_load_json.load(update_dict)
+    errors = user_update_schema_load_json.validate(update_dict)
     assert not errors
 
 
@@ -81,7 +81,7 @@ def test_user_update_schema_rejects_invalid_attribute_pairs(user_attribute, user
     }
 
     with pytest.raises(ValidationError):
-        data, errors = user_update_schema_load_json.load(update_dict)
+        user_update_schema_load_json.load(update_dict)
 
 
 @pytest.mark.parametrize('user_attribute', [
@@ -96,7 +96,7 @@ def test_user_update_schema_rejects_disallowed_attribute_keys(user_attribute):
     from app.schemas import user_update_schema_load_json
 
     with pytest.raises(ValidationError) as excinfo:
-        data, errors = user_update_schema_load_json.load(update_dict)
+        user_update_schema_load_json.load(update_dict)
 
     assert excinfo.value.messages['_schema'][0] == 'Unknown field name {}'.format(user_attribute)
 

tests/app/user/test_rest.py

@@ -116,6 +116,7 @@ def test_post_user(admin_request, notify_db_session):
     json_resp = admin_request.post('user.create_user', _data=data, _expected_status=201)
 
     user = User.query.filter_by(email_address='user@digital.cabinet-office.gov.uk').first()
+    assert user.check_password("password")
     assert json_resp['data']['email_address'] == user.email_address
     assert json_resp['data']['id'] == str(user.id)
     assert user.auth_type == EMAIL_AUTH_TYPE
@@ -888,7 +889,7 @@ def test_cannot_update_user_password_using_attributes_method(admin_request, samp
         _data={'password': 'foo'},
         _expected_status=400
     )
-    assert resp['message']['_schema'] == ['Unknown field name password']
+    assert resp == {'message': {'_schema': ['Unknown field name password']}, 'result': 'error'}
 
 
 def test_get_orgs_and_services_nests_services(admin_request, sample_user):