Increase unit testing for BOM item model

InvenTree/part/test_bom_item.py

@@ -43,3 +43,55 @@ class BomItemTest(TestCase):
             # A validation error should be raised here
             item = BomItem.objects.create(part=self.bob, sub_part=self.bob, quantity=7)
             item.clean()
+
+    def test_overage(self):
+        """ Test that BOM line overages are calculated correctly """
+
+        item = BomItem.objects.get(part=100, sub_part=50)
+        
+        q = 300
+
+        item.quantity = q
+
+        # Test empty overage
+        n = item.get_overage_quantity(q)
+        self.assertEqual(n, 0)
+
+        # Test improper overage
+        item.overage = 'asf234?'
+        n = item.get_overage_quantity(q)
+        self.assertEqual(n, 0)
+        
+        # Test absolute overage
+        item.overage = '3'
+        n = item.get_overage_quantity(q)
+        self.assertEqual(n, 3)
+
+        # Test percentage-based overage
+        item.overage = '5.0 % '
+        n = item.get_overage_quantity(q)
+        self.assertEqual(n, 15)
+
+        # Calculate total required quantity
+        # Quantity = 300 (+ 5%)
+        # Get quantity required to build B = 10
+        # Q * B = 3000 + 5% = 3150
+        n = item.get_required_quantity(10)
+
+        self.assertEqual(n, 3150)
+
+    def test_item_hash(self):
+        """ Test BOM item hash encoding """
+
+        item = BomItem.objects.get(part=100, sub_part=50)
+        
+        h1 = item.get_item_hash()
+
+        # Change data - the hash must change
+        item.quantity += 1
+
+        h2 = item.get_item_hash()
+
+        item.validate_hash()
+
+        self.assertNotEqual(h1, h2)