Add some BomItem tests

- Add a bom fixture

InvenTree/part/fixtures/bom.yaml

@@ -0,0 +1,29 @@
+# Construct a BOM for item 100 'Bob'
+
+# 10 x M2x4 LPHS
+- model: part.bomitem
+  fields:
+    part: 100
+    sub_part: 1
+    quantity: 10
+
+# 40 x R_2K2_0805
+- model: part.bomitem
+  fields:
+    part: 100
+    sub_part: 3
+    quantity: 40
+
+# 25 x C_22N_0805
+- model: part.bomitem
+  fields:
+    part: 100
+    sub_part: 5
+    quantity: 25
+
+# 3 x Orphan
+- model: part.bomitem
+  fields:
+    part: 100
+    sub_part: 50
+    quantity: 3

InvenTree/part/fixtures/part.yaml

@@ -5,6 +5,7 @@
     name: 'M2x4 LPHS'
     description: 'M2x4 low profile head screw'
     category: 8
+
 - model: part.part
   fields:
     name: 'M3x12 SHCS'
@@ -18,6 +19,7 @@
     name: 'R_2K2_0805'
     description: '2.2kOhm resistor in 0805 package'
     category: 2
+
 - model: part.part
   fields:
     name: 'R_4K7_0603'
@@ -39,7 +41,17 @@
     category: 7
 
 - model: part.part
+  pk: 50
   fields:
     name: 'Orphan'
     description: 'A part without a category'
     category: null
+
+# A part that can be made from other parts
+- model: part.part
+  pk: 100
+  fields:
+    name: 'Bob'
+    description: 'Can we build it?'
+    buildable: true
+    

InvenTree/part/test_bom_item.py

@@ -1,7 +1,37 @@
 from django.test import TestCase
 
+from .models import Part
+
 
 class BomItemTest(TestCase):
 
+    fixtures = [
+        'category',
+        'part',
+        'location',
+        'bom',
+    ]
+
     def setUp(self):
-        pass
+        self.bob = Part.objects.get(id=100)
+        self.orphan = Part.objects.get(name='Orphan')
+
+    def test_has_bom(self):
+        self.assertFalse(self.orphan.has_bom)
+        self.assertTrue(self.bob.has_bom)
+
+        self.assertEqual(self.bob.bom_count, 4)
+
+    def test_in_bom(self):
+        parts = self.bob.required_parts()
+
+        self.assertIn(self.orphan, parts)
+
+    def test_bom_export(self):
+        parts = self.bob.required_parts()
+
+        data = self.bob.export_bom(format='csv')
+
+        for p in parts:
+            self.assertIn(p.name, data)
+            self.assertIn(p.description, data)