Allow custom icons to be cleared (#9185)

* Allow custom icons to be cleared

- Closes https://github.com/inventree/InvenTree/issues/9182

* Bump API version

* Update unit test

* Loosen test requirements

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,13 +1,17 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 315
+INVENTREE_API_VERSION = 316
 
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 
 INVENTREE_API_TEXT = """
 
+v316 - 2025-02-26 : https://github.com/inventree/InvenTree/pull/9185
+    - Allow 'icon' field to be nullified in the PartCategory API
+    - Allow 'custom_icon' field to be nullified in the StockLocation API
+
 v315 - 2025-02-22 : https://github.com/inventree/InvenTree/pull/9150
     - Remove outdated 'url' field from some API endpoints
 

src/backend/InvenTree/part/migrations/0133_alter_partcategory__icon.py

@@ -0,0 +1,27 @@
+# Generated by Django 4.2.19 on 2025-02-25 22:14
+
+import common.icons
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("part", "0132_partparametertemplate_selectionlist"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="partcategory",
+            name="_icon",
+            field=models.CharField(
+                blank=True,
+                db_column="icon",
+                help_text="Icon (optional)",
+                max_length=100,
+                null=True,
+                validators=[common.icons.validate_icon],
+                verbose_name="Icon",
+            ),
+        ),
+    ]

src/backend/InvenTree/part/models.py

@@ -128,6 +128,7 @@ class PartCategory(InvenTree.models.InvenTreeTree):
 
     _icon = models.CharField(
         blank=True,
+        null=True,
         max_length=100,
         verbose_name=_('Icon'),
         help_text=_('Icon (optional)'),

src/backend/InvenTree/part/serializers.py

@@ -136,7 +136,11 @@ class CategorySerializer(
     )
 
     icon = serializers.CharField(
-        required=False, allow_blank=True, help_text=_('Icon (optional)'), max_length=100
+        required=False,
+        allow_blank=True,
+        allow_null=True,
+        help_text=_('Icon (optional)'),
+        max_length=100,
     )
 
     parent_default_location = serializers.IntegerField(read_only=True)

src/backend/InvenTree/part/test_category.py

@@ -419,7 +419,7 @@ class CategoryTest(TestCase):
         """Test the category icon."""
         # No default icon set
         cat = PartCategory.objects.create(name='Test Category')
-        self.assertEqual(cat.icon, '')
+        self.assertIn(cat.icon, ['', None])
 
         # Set a default icon
         InvenTreeSetting.set_setting('PART_CATEGORY_DEFAULT_ICON', 'ti:package:outline')
@@ -428,7 +428,7 @@ class CategoryTest(TestCase):
         # Set custom icon to default icon and assert that it does not get written to the database
         cat.icon = 'ti:package:outline'
         cat.save()
-        self.assertEqual(cat._icon, '')
+        self.assertIn(cat._icon, ['', None])
 
         # Set a different custom icon and assert that it takes precedence
         cat.icon = 'ti:tag:outline'
@@ -439,4 +439,4 @@ class CategoryTest(TestCase):
         # Test that the icon can be set to None again
         cat.icon = ''
         cat.save()
-        self.assertEqual(cat.icon, '')
+        self.assertIn(cat.icon, ['', None])

src/backend/InvenTree/stock/migrations/0114_alter_stocklocation_custom_icon.py

@@ -0,0 +1,27 @@
+# Generated by Django 4.2.19 on 2025-02-25 22:14
+
+import common.icons
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("stock", "0113_stockitem_status_custom_key_and_more"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="stocklocation",
+            name="custom_icon",
+            field=models.CharField(
+                blank=True,
+                db_column="icon",
+                help_text="Icon (optional)",
+                max_length=100,
+                null=True,
+                validators=[common.icons.validate_icon],
+                verbose_name="Icon",
+            ),
+        ),
+    ]

src/backend/InvenTree/stock/models.py

@@ -171,6 +171,7 @@ class StockLocation(
 
     custom_icon = models.CharField(
         blank=True,
+        null=True,
         max_length=100,
         verbose_name=_('Icon'),
         help_text=_('Icon (optional)'),