Handle wrong value of DM_G12_RECOVERY_SUPPLIER_IDS

It's set from an environment variable. So it should always be set to something. However, in case we mess things up, log the error and treat the supplier as not part of the G12 recovery.

app/main/helpers/suppliers.py

@@ -71,6 +71,15 @@ def get_company_details_from_supplier(supplier):
 
 
 def is_g12_recovery_supplier(supplier_id: Union[str, int]) -> bool:
-    supplier_ids = current_app.config.get('DM_G12_RECOVERY_SUPPLIER_IDS') or ''
-
-    return str(supplier_id) in supplier_ids.split(sep=',')
+    supplier_ids_string = current_app.config.get('DM_G12_RECOVERY_SUPPLIER_IDS') or ''
+
+    try:
+        supplier_ids = [int(s) for s in supplier_ids_string.split(sep=',')]
+    except AttributeError as e:
+        current_app.logger.error("DM_G12_RECOVERY_SUPPLIER_IDS not a string", extra={'error': str(e)})
+        return False
+    except ValueError as e:
+        current_app.logger.error("DM_G12_RECOVERY_SUPPLIER_IDS not a list of supplier IDs", extra={'error': str(e)})
+        return False
+
+    return int(supplier_id) in supplier_ids

tests/app/main/helpers/test_suppliers.py

@@ -2,10 +2,13 @@
 from flask_wtf import FlaskForm
 from wtforms import StringField
 from wtforms.validators import Length
-from app.main.helpers.suppliers import get_country_name_from_country_code, supplier_company_details_are_complete
+from app.main.helpers.suppliers import get_country_name_from_country_code, supplier_company_details_are_complete, \
+    is_g12_recovery_supplier
 
 from dmtestutils.api_model_stubs import SupplierStub
 
+from tests.app.helpers import BaseApplicationTest
+
 
 class TestGetCountryNameFromCountryCode:
     @pytest.mark.parametrize(
@@ -49,3 +52,22 @@ class FormForTest(FlaskForm):
     field_three = StringField('Field three?', validators=[
         Length(max=5, message="Field three must be under 5 characters.")
     ])
+
+
+class TestG12RecoverySupplier(BaseApplicationTest):
+    @pytest.mark.parametrize(
+        'g12_recovery_supplier_ids, expected_result',
+        [
+            (None, False),
+            ('', False),
+            (42, False),
+            ('12:32', False),
+            ([123456, 789012], False),
+            ('123456', True),
+            ('123456,789012', True),
+        ]
+    )
+    def test_returns_expected_value_for_input(self, g12_recovery_supplier_ids, expected_result):
+        with self.app.app_context():
+            self.app.config['DM_G12_RECOVERY_SUPPLIER_IDS'] = g12_recovery_supplier_ids
+            assert is_g12_recovery_supplier('123456') is expected_result