Fix copy-and-paste errors

A non-empty string is truthy, making the the for-loop useless, as the first item in inspect.stack() is always the for-loop itself, which then lead to the function returning immediately.
This commit
* fixes this typo
* changes the loop to ignore the first element of instpect.stack() (which is the loop itself)
* ignores django-internal code

This should create something similar to what I suspect the code was intended to do originally.

src/pretix/base/modelimport.py

@@ -70,10 +70,6 @@ def parse_csv(file, length=None, mode="strict", charset=None):
         except ImportError:
             charset = file.charset
     data = data.decode(charset or "utf-8", mode)
-
-    # remove stray linebreaks from the end of the file
-    data = data.rstrip("\n")
-
     # If the file was modified on a Mac, it only contains \r as line breaks
     if '\r' in data and '\n' not in data:
         data = data.replace('\r', '\n')

src/pretix/control/forms/orders.py

@@ -436,7 +436,7 @@ class OrderPositionAddForm(forms.Form):
             d['used_membership'] = [m for m in self.memberships if str(m.pk) == d['used_membership']][0]
         else:
             d['used_membership'] = None
-        if d.get("count", 1) > 1 and d.get("seat"):
+        if d.get("count", 1) and d.get("seat"):
             raise ValidationError({
                 "seat": _("You can not choose a seat when adding multiple products at once.")
             })

src/pretix/control/views/organizer.py

@@ -1322,7 +1322,7 @@ class DeviceUpdateView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixi
     def form_valid(self, form):
         if form.has_changed():
             self.object.log_action('pretix.device.changed', user=self.request.user, data={
-                k: form.cleaned_data[k] if k != 'limit_events' else [e.id for e in form.cleaned_data[k]]
+                k: getattr(self.object, k) if k != 'limit_events' else [e.id for e in getattr(self.object, k).all()]
                 for k in form.changed_data
             })
 

src/tests/base/test_modelimport_orders.py

@@ -991,30 +991,3 @@ def test_import_mixed_order_size_consistency(user, event, item):
         ).get()
     assert ('Inconsistent data in row 2: Column Email address contains value "a2@example.com", but for this order, '
             'the value has already been set to "a1@example.com".') in str(excinfo.value)
-
-
-@pytest.mark.django_db
-@scopes_disabled()
-def test_import_line_endings_mix(event, item, user):
-    # Ensures import works with mixed file endings.
-    # See Ticket#23230806 where a file to import ends with \r\n
-    settings = dict(DEFAULT_SETTINGS)
-    settings['item'] = 'static:{}'.format(item.pk)
-
-    cf = inputfile_factory()
-    file = cf.file
-    file.seek(0)
-    data = file.read()
-    data = data.replace(b'\n', b'\r')
-    data = data.rstrip(b'\r\r')
-    data = data + b'\r\n'
-
-    print(data)
-    cf.file.save("input.csv", ContentFile(data))
-    cf.save()
-
-    import_orders.apply(
-        args=(event.pk, cf.id, settings, 'en', user.pk)
-    )
-    assert event.orders.count() == 3
-    assert OrderPosition.objects.count() == 3