Part stocktake (#4069)

* Remove stat context variables

* Revert "Remove stat context variables"

This reverts commit 0989c308d0.

* Allow longer timeout for image download tests

* Create PartStocktake model

Model for representing stocktake entries against any given part

* Admin interface support for new model

* Adds API endpoint for listing stocktake information

* Bump API version

* Enable filtering and ordering for API endpoint

* Add model to permission group

* Add UI hooks for displaying stocktake data for a particular part

* Fix encoded type for 'quantity' field

* Load stocktake table for part

* Add "stocktake" button

* Add "note" field for stocktake

* Add user information when performing stocktake

* First pass at UI elements for performing stocktake

* Add user information to stocktake table

* Auto-calculate quantity based on available stock items

* add stocktake data as tabular inline (admin)

* js linting

* Add indication that a stock item has not been updated recently

* Display last stocktake information on part page

* js style fix

* Test fix for ongoing CI issues

* Add configurable option for controlling default "delete_on_deplete" behaviour

* Add id values to cells

* Hide action buttons (at least for now)

* Adds refresh button to table

* Add API endpoint to delete or edit stocktake entries

* Adds unit test for API list endpoint

* javascript linting

* More unit testing

* Add Part API filter for stocktake

* Add 'last_stocktake' field to Part model

- Gets filled out automatically when a new PartStocktake instance is created

* Update part table to include last_stocktake date

* Add simple unit test

* Fix test

InvenTree/part/test_part.py

@@ -17,7 +17,8 @@ from InvenTree import version
 from InvenTree.helpers import InvenTreeTestCase
 
 from .models import (Part, PartCategory, PartCategoryStar, PartRelated,
-                     PartStar, PartTestTemplate, rename_part_image)
+                     PartStar, PartStocktake, PartTestTemplate,
+                     rename_part_image)
 from .templatetags import inventree_extras
 
 
@@ -338,6 +339,19 @@ class PartTest(TestCase):
         self.r2.delete()
         self.assertEqual(PartRelated.objects.count(), 0)
 
+    def test_stocktake(self):
+        """Test for adding stocktake data"""
+
+        # Grab a part
+        p = Part.objects.all().first()
+
+        self.assertIsNone(p.last_stocktake)
+
+        ps = PartStocktake.objects.create(part=p, quantity=100)
+
+        self.assertIsNotNone(p.last_stocktake)
+        self.assertEqual(p.last_stocktake, ps.date)
+
 
 class TestTemplateTest(TestCase):
     """Unit test for the TestTemplate class"""