Unit test speed improvements (#4463)

* Unit test speed improvements

- Move from insantiating data in setUp to setUpTestData

* Update UserMixin class for API testing

* Bunch of test updates

* Further test updates

* Test fixes

* Add allowances for exchange rate server not responding

* Fixes for group role test

InvenTree/build/test_build.py

@@ -29,7 +29,8 @@ class BuildTestBase(TestCase):
         'users',
     ]
 
-    def setUp(self):
+    @classmethod
+    def setUpTestData(cls):
         """Initialize data to use for these tests.
 
         The base Part 'assembly' has a BOM consisting of three parts:
@@ -45,27 +46,29 @@ class BuildTestBase(TestCase):
 
         """
 
+        super().setUpTestData()
+
         # Create a base "Part"
-        self.assembly = Part.objects.create(
+        cls.assembly = Part.objects.create(
             name="An assembled part",
             description="Why does it matter what my description is?",
             assembly=True,
             trackable=True,
         )
 
-        self.sub_part_1 = Part.objects.create(
+        cls.sub_part_1 = Part.objects.create(
             name="Widget A",
             description="A widget",
             component=True
         )
 
-        self.sub_part_2 = Part.objects.create(
+        cls.sub_part_2 = Part.objects.create(
             name="Widget B",
             description="A widget",
             component=True
         )
 
-        self.sub_part_3 = Part.objects.create(
+        cls.sub_part_3 = Part.objects.create(
             name="Widget C",
             description="A widget",
             component=True,
@@ -73,63 +76,63 @@ class BuildTestBase(TestCase):
         )
 
         # Create BOM item links for the parts
-        self.bom_item_1 = BomItem.objects.create(
-            part=self.assembly,
-            sub_part=self.sub_part_1,
+        cls.bom_item_1 = BomItem.objects.create(
+            part=cls.assembly,
+            sub_part=cls.sub_part_1,
             quantity=5
         )
 
-        self.bom_item_2 = BomItem.objects.create(
-            part=self.assembly,
-            sub_part=self.sub_part_2,
+        cls.bom_item_2 = BomItem.objects.create(
+            part=cls.assembly,
+            sub_part=cls.sub_part_2,
             quantity=3,
             optional=True
         )
 
         # sub_part_3 is trackable!
-        self.bom_item_3 = BomItem.objects.create(
-            part=self.assembly,
-            sub_part=self.sub_part_3,
+        cls.bom_item_3 = BomItem.objects.create(
+            part=cls.assembly,
+            sub_part=cls.sub_part_3,
             quantity=2
         )
 
         ref = generate_next_build_reference()
 
         # Create a "Build" object to make 10x objects
-        self.build = Build.objects.create(
+        cls.build = Build.objects.create(
             reference=ref,
             title="This is a build",
-            part=self.assembly,
+            part=cls.assembly,
             quantity=10,
             issued_by=get_user_model().objects.get(pk=1),
         )
 
         # Create some build output (StockItem) objects
-        self.output_1 = StockItem.objects.create(
-            part=self.assembly,
+        cls.output_1 = StockItem.objects.create(
+            part=cls.assembly,
             quantity=3,
             is_building=True,
-            build=self.build
+            build=cls.build
         )
 
-        self.output_2 = StockItem.objects.create(
-            part=self.assembly,
+        cls.output_2 = StockItem.objects.create(
+            part=cls.assembly,
             quantity=7,
             is_building=True,
-            build=self.build,
+            build=cls.build,
         )
 
         # Create some stock items to assign to the build
-        self.stock_1_1 = StockItem.objects.create(part=self.sub_part_1, quantity=3)
-        self.stock_1_2 = StockItem.objects.create(part=self.sub_part_1, quantity=100)
+        cls.stock_1_1 = StockItem.objects.create(part=cls.sub_part_1, quantity=3)
+        cls.stock_1_2 = StockItem.objects.create(part=cls.sub_part_1, quantity=100)
 
-        self.stock_2_1 = StockItem.objects.create(part=self.sub_part_2, quantity=5)
-        self.stock_2_2 = StockItem.objects.create(part=self.sub_part_2, quantity=5)
-        self.stock_2_3 = StockItem.objects.create(part=self.sub_part_2, quantity=5)
-        self.stock_2_4 = StockItem.objects.create(part=self.sub_part_2, quantity=5)
-        self.stock_2_5 = StockItem.objects.create(part=self.sub_part_2, quantity=5)
+        cls.stock_2_1 = StockItem.objects.create(part=cls.sub_part_2, quantity=5)
+        cls.stock_2_2 = StockItem.objects.create(part=cls.sub_part_2, quantity=5)
+        cls.stock_2_3 = StockItem.objects.create(part=cls.sub_part_2, quantity=5)
+        cls.stock_2_4 = StockItem.objects.create(part=cls.sub_part_2, quantity=5)
+        cls.stock_2_5 = StockItem.objects.create(part=cls.sub_part_2, quantity=5)
 
-        self.stock_3_1 = StockItem.objects.create(part=self.sub_part_3, quantity=1000)
+        cls.stock_3_1 = StockItem.objects.create(part=cls.sub_part_3, quantity=1000)
 
 
 class BuildTest(BuildTestBase):