made tests robust against changing order

input/tests/models.py

@@ -11,6 +11,15 @@ class ModelTestCase(TestCase):
     def setUpTestData(cls):
         cls.account = Account.objects.create(code='1234', description='blabla')
 
+    def assertLen(self, value, length, msg=None):
+        self.assertEqual(len(value), length, msg)
+
+    def assertStartsWith(self, value, start, msg=None):
+        self.assertTrue(f'{value}'.startswith(f'{start}'), msg)
+
+    def assertEndsWith(self, value, end, msg=None):
+        self.assertTrue(f'{value}'.endswith(f'{end}'), msg)
+
     def test_set_granted(self):
         """ test if the model function set_granted() works as intended """
         obj = HonoraryCertificate.objects.create(realname='hurzel', email='hurzel@web.de')
@@ -72,17 +81,18 @@ class ModelTestCase(TestCase):
         acc = self.account
         startdate = date(2022, 1, 1)
         obj = Project.objects.create(account=acc, name='testproject', start=startdate)
-        self.assertEqual(obj.pid, "123400000001")
-        self.assertEqual(obj.account.code, "1234")
+        self.assertLen(obj.pid, len(acc.code) + 8)
+        self.assertStartsWith(obj.pid, acc.code)
+        self.assertEndsWith(obj.pid, obj.id)
 
         obj2 = Project.objects.create(account=acc, name='testproject2', start=startdate)
-        self.assertEqual(obj2.pid, "123400000002")
+        self.assertEndsWith(obj2.pid, obj.id + 1)
 
         olddate = date(2021, 12, 31)
-        obj4 = Project.objects.create(account=acc, name='testproject2', start=olddate)
+        Project.objects.create(account=acc, name='testproject2', start=olddate)
 
-        obj3 = Project.objects.create(account=acc, name='testproject2', start=startdate)
-        self.assertEqual(obj3.pid, "123400000004")
+        obj4 = Project.objects.create(account=acc, name='testproject2', start=startdate)
+        self.assertEndsWith(obj4.pid, obj.id + 3)
 
     def test_literature(self):
         obj = Literature.objects.create(cost='100', notes='jolo', selfbuy_give_data=False)