Closes #12988: Introduce custom field choice sets (#13195)

* Initial work on custom field choice sets

* Rename choices to extra_choices (prep for #12194)

* Remove CustomField.choices

* Add & update tests

* Clean up table columns

* Add order_alphanetically boolean for choice sets

* Introduce ArrayColumn for choice lists

* Show dependent custom fields on choice set view

* Update custom fields documentation

* Introduce ArrayWidget for more convenient editing of choices

* Incorporate PR feedback

* Misc cleanup

netbox/extras/forms/bulk_import.py

@@ -9,10 +9,13 @@ from extras.models import *
 from extras.utils import FeatureQuery
 from netbox.forms import NetBoxModelImportForm
 from utilities.forms import CSVModelForm
-from utilities.forms.fields import CSVChoiceField, CSVContentTypeField, CSVMultipleContentTypeField, SlugField
+from utilities.forms.fields import (
+    CSVChoiceField, CSVContentTypeField, CSVModelChoiceField, CSVMultipleContentTypeField, SlugField,
+)
 
 __all__ = (
     'ConfigTemplateImportForm',
+    'CustomFieldChoiceSetImportForm',
     'CustomFieldImportForm',
     'CustomLinkImportForm',
     'ExportTemplateImportForm',
@@ -39,10 +42,11 @@ class CustomFieldImportForm(CSVModelForm):
         required=False,
         help_text=_("Object type (for object or multi-object fields)")
     )
-    choices = SimpleArrayField(
-        base_field=forms.CharField(),
+    choice_set = CSVModelChoiceField(
+        queryset=CustomFieldChoiceSet.objects.all(),
+        to_field_name='name',
         required=False,
-        help_text=_('Comma-separated list of field choices')
+        help_text=_('Choice set (for selection fields)')
     )
     ui_visibility = CSVChoiceField(
         choices=CustomFieldVisibilityChoices,
@@ -53,8 +57,22 @@ class CustomFieldImportForm(CSVModelForm):
         model = CustomField
         fields = (
             'name', 'label', 'group_name', 'type', 'content_types', 'object_type', 'required', 'description',
-            'search_weight', 'filter_logic', 'default', 'choices', 'weight', 'validation_minimum', 'validation_maximum',
-            'validation_regex', 'ui_visibility', 'is_cloneable',
+            'search_weight', 'filter_logic', 'default', 'choice_set', 'weight', 'validation_minimum',
+            'validation_maximum', 'validation_regex', 'ui_visibility', 'is_cloneable',
+        )
+
+
+class CustomFieldChoiceSetImportForm(CSVModelForm):
+    extra_choices = SimpleArrayField(
+        base_field=forms.CharField(),
+        required=False,
+        help_text=_('Comma-separated list of field choices')
+    )
+
+    class Meta:
+        model = CustomFieldChoiceSet
+        fields = (
+            'name', 'description', 'extra_choices', 'order_alphabetically',
         )