chore: add GUT test framework

addons/gut/test/unit/test_orphan_counter.gd

@@ -0,0 +1,58 @@
+extends GutInternalTester
+
+func test_can_make_one():
+	assert_not_null(GutUtils.OrphanCounter.new())
+
+
+class TestOrphanIds:
+	extends GutInternalTester
+
+	var new_orphans = []
+
+	func new_primed_orphan_counter():
+		var oc = partial_double(GutUtils.OrphanCounter).new()
+		# record everything that already exists, root is sometimes in
+		# the list?
+		oc.record_orphans('none')
+		return oc
+
+
+	func test_recording_orphans_returns_instance_ids():
+		var oc = new_primed_orphan_counter()
+		var n1 = autofree(Node.new())
+		var orphans = oc.record_orphans('test_group')
+		assert_eq(orphans, [n1.get_instance_id()])
+
+
+	func test_can_get_orphans_by_group():
+		var oc = new_primed_orphan_counter()
+		var n1 = autofree(Node.new())
+		var n2 = autofree(Node.new())
+		oc.record_orphans('test_group')
+		var results = oc.get_orphan_ids('test_group')
+		results = oc.convert_instance_ids_to_valid_instances(results)
+		results.sort()
+		assert_true(results.all(func(e):
+			return [n1, n2].has(e)))
+
+
+	func test_can_get_orphans_by_group_and_subgroup():
+		var oc = new_primed_orphan_counter()
+		var n1 = autofree(Node.new())
+		var n2 = autofree(Node.new())
+		oc.record_orphans('group', 'subgroup')
+		var results = oc.get_orphan_ids('group', 'subgroup')
+		results = oc.convert_instance_ids_to_valid_instances(results)
+		results.sort()
+		assert_true(results.all(func(e):
+			return [n1, n2].has(e)))
+
+
+	func test_can_get_all_subgroup_oprhans_using_group():
+		var oc = new_primed_orphan_counter()
+		var n1 = autofree(Node.new())
+		var n2 = autofree(Node.new())
+		oc.record_orphans('group', 'subgroup')
+		var result = oc.get_orphan_ids("group")
+		assert_eq(result.size(), 2)
+