Move translation of ValueError to ValidationError into to_python where it belongs

netbox/utilities/forms/fields/expandable.py

@@ -30,7 +30,10 @@ class ExpandableNameField(forms.CharField):
         if not value:
             return ''
         if re.search(ALPHANUMERIC_EXPANSION_PATTERN, value):
-            return list(expand_alphanumeric_pattern(value))
+            try:
+                return list(expand_alphanumeric_pattern(value))
+            except ValueError as e:
+                raise forms.ValidationError(*e.args)
         return [value]
 
 

netbox/utilities/forms/utils.py

@@ -96,12 +96,7 @@ def expand_alphanumeric_pattern(pattern):
     if not re.search(ALPHANUMERIC_EXPANSION_PATTERN, pattern):
         raise ValueError(f"String {repr(pattern)} contains no valid alphanumeric patterns")
 
-    try:
-        yield from expand_alphanumeric_pattern_impl(pattern)
-    except ValueError as e:
-        # Unit tests expect forms.ValidationError to be thrown if patterns were "valid" at a first glance,
-        # but then turned out to be invalid when looking closer. So we preserve this behaviour here.
-        raise forms.ValidationError(*e.args)
+    yield from expand_alphanumeric_pattern_impl(pattern)
 
 
 def expand_ipaddress_pattern(string, family):

netbox/utilities/tests/test_forms.py

@@ -269,19 +269,19 @@ class ExpandAlphanumeric(TestCase):
             sorted(expand_alphanumeric_pattern('r[8--9]a'))
 
     def test_invalid_range_alphanumeric(self):
-        with self.assertRaises(forms.ValidationError):
+        with self.assertRaises(ValueError):
             sorted(expand_alphanumeric_pattern('r[9-a]a'))
 
-        with self.assertRaises(forms.ValidationError):
+        with self.assertRaises(ValueError):
             sorted(expand_alphanumeric_pattern('r[a-9]a'))
 
     def test_invalid_range_bounds(self):
-        with self.assertRaises(forms.ValidationError):
+        with self.assertRaises(ValueError):
             sorted(expand_alphanumeric_pattern('r[9-8]a'))
             sorted(expand_alphanumeric_pattern('r[b-a]a'))
 
     def test_invalid_range_len(self):
-        with self.assertRaises(forms.ValidationError):
+        with self.assertRaises(ValueError):
             sorted(expand_alphanumeric_pattern('r[a-bb]a'))
 
     def test_invalid_set(self):