chore(ruff): Enable RET rules and add explicit fallbacks

Adopt Ruff `RET` to improve return-flow consistency across the codebase.
Simplify control flow by removing redundant `else` blocks after
`return`, and add explicit `return None` (or equivalent) fallbacks
where appropriate to preserve existing behavior.

Fixes #21411

netbox/utilities/fields.py

@@ -133,15 +133,14 @@ class RestrictedGenericForeignKey(GenericForeignKey):
             ct_id = getattr(obj, ct_attname)
             if ct_id is None:
                 return None
-            else:
-                if model := self.get_content_type(
-                    id=ct_id, using=obj._state.db
-                ).model_class():
-                    return (
-                        model._meta.pk.get_prep_value(getattr(obj, self.fk_field)),
-                        model,
-                    )
-                return None
+            if model := self.get_content_type(
+                id=ct_id, using=obj._state.db
+            ).model_class():
+                return (
+                    model._meta.pk.get_prep_value(getattr(obj, self.fk_field)),
+                    model,
+                )
+            return None
 
         return (
             ret_val,

netbox/utilities/forms/fields/expandable.py

@@ -50,6 +50,6 @@ class ExpandableIPAddressField(forms.CharField):
         # Hackish address family detection but it's all we have to work with
         if '.' in value and re.search(IP4_EXPANSION_PATTERN, value):
             return list(expand_ipaddress_pattern(value, 4))
-        elif ':' in value and re.search(IP6_EXPANSION_PATTERN, value):
+        if ':' in value and re.search(IP6_EXPANSION_PATTERN, value):
             return list(expand_ipaddress_pattern(value, 6))
         return [value]

netbox/utilities/forms/utils.py

@@ -139,7 +139,7 @@ def get_field_value(form, field_name):
 
     if form.is_bound and field_name in form.data:
         if (value := form.data[field_name]) is None:
-            return
+            return None
         if hasattr(field, 'valid_value') and field.valid_value(value):
             return value
 

netbox/utilities/html.py

@@ -37,8 +37,7 @@ def foreground_color(bg_color, dark='000000', light='ffffff'):
     r, g, b = [int(bg_color[c:c + 2], 16) for c in (0, 2, 4)]
     if r * 0.299 + g * 0.587 + b * 0.114 > THRESHOLD:
         return dark
-    else:
-        return light
+    return light
 
 
 def highlight(value, highlight, trim_pre=None, trim_post=None, trim_placeholder='...'):

netbox/utilities/jobs.py

@@ -25,7 +25,7 @@ def process_request_as_job(view, request, name=None):
 
     # Check that the request that is not already being processed as a background job (would be a loop)
     if is_background_request(request):
-        return
+        return None
 
     # Create a serializable copy of the original request
     request_copy = copy_safe_request(request)

netbox/utilities/proxy.py

@@ -54,3 +54,4 @@ def resolve_proxies(url=None, protocol=None, context=None):
         router = import_string(item) if type(item) is str else item
         if proxies := router().route(url=url, protocol=protocol, context=context):
             return proxies
+    return None

netbox/utilities/query.py

@@ -67,7 +67,7 @@ def reapply_model_ordering(queryset: QuerySet) -> QuerySet:
     # MPTT-based models are exempt from this; use caution when annotating querysets of these models
     if any(isinstance(manager, TreeManager) for manager in queryset.model._meta.local_managers):
         return queryset
-    elif queryset.ordered:
+    if queryset.ordered:
         return queryset
 
     ordering = queryset.model._meta.ordering

netbox/utilities/rqworker.py

@@ -34,3 +34,4 @@ def get_rq_retry():
     retry_interval = get_config().RQ_RETRY_INTERVAL
     if retry_max:
         return Retry(max=retry_max, interval=retry_interval)
+    return None

netbox/utilities/tables.py

@@ -33,13 +33,13 @@ def get_table_for_model(model, name=None):
     try:
         return import_string(f'{model._meta.app_label}.tables.{name}')
     except ImportError:
-        return
+        return None
 
 
 def get_table_ordering(request, table):
     """
-    Given a request, return the prescribed table ordering, if any. This may be necessary to determine prior to rendering
-    the table itself.
+    Given a request, return the prescribed table ordering, if any.
+    This may be necessary to determine before rendering the table itself.
     """
     # Check for an explicit ordering
     if 'sort' in request.GET:
@@ -49,6 +49,7 @@ def get_table_ordering(request, table):
     if request.user.is_authenticated:
         if preference := request.user.config.get(f'tables.{table.__name__}.ordering'):
             return preference
+    return None
 
 
 def linkify_phone(value):

netbox/utilities/templatetags/builtins/filters.py

@@ -227,12 +227,11 @@ def isodate(value):
     if type(value) is datetime.date:
         text = value.isoformat()
         return mark_safe(f'<span title="{naturalday(value)}">{text}</span>')
-    elif type(value) is datetime.datetime:
+    if type(value) is datetime.datetime:
         local_value = localtime(value) if value.tzinfo else value
         text = local_value.date().isoformat()
         return mark_safe(f'<span title="{naturaltime(value)}">{text}</span>')
-    else:
-        return ''
+    return ''
 
 
 @register.filter()

netbox/utilities/templatetags/form_helpers.py

@@ -37,10 +37,9 @@ def widget_type(field):
     """
     if hasattr(field, 'widget'):
         return field.widget.__class__.__name__.lower()
-    elif hasattr(field, 'field'):
+    if hasattr(field, 'field'):
         return field.field.widget.__class__.__name__.lower()
-    else:
-        return None
+    return None
 
 
 #

netbox/utilities/templatetags/helpers.py

@@ -199,14 +199,13 @@ def humanize_speed(speed):
         return ''
     if speed >= 1000000000 and speed % 1000000000 == 0:
         return '{} Tbps'.format(int(speed / 1000000000))
-    elif speed >= 1000000 and speed % 1000000 == 0:
+    if speed >= 1000000 and speed % 1000000 == 0:
         return '{} Gbps'.format(int(speed / 1000000))
-    elif speed >= 1000 and speed % 1000 == 0:
+    if speed >= 1000 and speed % 1000 == 0:
         return '{} Mbps'.format(int(speed / 1000))
-    elif speed >= 1000:
+    if speed >= 1000:
         return '{} Mbps'.format(float(speed) / 1000)
-    else:
-        return '{} Kbps'.format(speed)
+    return '{} Kbps'.format(speed)
 
 
 def _humanize_megabytes(mb, divisor=1000):
@@ -373,8 +372,7 @@ def querystring(request, **kwargs):
     querystring = querydict.urlencode(safe='/')
     if querystring:
         return '?' + querystring
-    else:
-        return ''
+    return ''
 
 
 @register.inclusion_tag('helpers/utilization_graph.html')

netbox/utilities/testing/filtersets.py

@@ -66,7 +66,7 @@ class BaseFilterSetTests:
             return [(f'{filter_name}_id', django_filters.ModelMultipleChoiceFilter)]
 
         # Many-to-many relationships (forward & backward)
-        elif type(field) in (ManyToManyField, ManyToManyRel):
+        if type(field) in (ManyToManyField, ManyToManyRel):
             filter_name = self.get_m2m_filter_name(field)
             filter_name = self.filter_name_map.get(filter_name, filter_name)
 

netbox/utilities/testing/views.py

@@ -635,10 +635,9 @@ class ViewTestCases:
                     available = ', '.join(self.csv_data.keys())
                     raise ValueError(f"Scenario '{scenario_name}' not found in csv_data. Available: {available}")
                 return '\n'.join(self.csv_data[scenario_name])
-            elif isinstance(self.csv_data, (tuple, list)):
+            if isinstance(self.csv_data, (tuple, list)):
                 return '\n'.join(self.csv_data)
-            else:
-                raise TypeError(f'csv_data must be a tuple, list, or dictionary, got {type(self.csv_data)}')
+            raise TypeError(f'csv_data must be a tuple, list, or dictionary, got {type(self.csv_data)}')
 
         def _get_update_csv_data(self):
             return self.csv_update_data, '\n'.join(self.csv_update_data)