--- a/test/testbintools.py	Fri Feb 28 18:07:14 2014 +0100
+++ b/test/testbintools.py	Sat Mar 01 15:40:31 2014 +0100
@@ -1,9 +1,37 @@
 import unittest
 import sys
-from target.arminstructions import ArmToken
+from ppci.target.arm.token import ArmToken
 from ppci.linker import Linker
 from ppci.objectfile import ObjectFile
 from ppci import CompilerError
+from ppci.tasks import EmptyTask, TaskRunner, TaskError
+
+
+class TaskTestCase(unittest.TestCase):
+    def testCircular(self):
+        t1 = EmptyTask('t1')
+        t2 = EmptyTask('t2')
+        t1.add_dependency(t2)
+        with self.assertRaises(TaskError):
+            t2.add_dependency(t1)
+
+    def testCircularDeeper(self):
+        t1 = EmptyTask('t1')
+        t2 = EmptyTask('t2')
+        t3 = EmptyTask('t3')
+        t1.add_dependency(t2)
+        t2.add_dependency(t3)
+        with self.assertRaises(TaskError):
+            t3.add_dependency(t1)
+
+    def testSort(self):
+        t1 = EmptyTask('t1')
+        t2 = EmptyTask('t2')
+        runner = TaskRunner()
+        t1.add_dependency(t2)
+        runner.add_task(t1)
+        runner.add_task(t2)
+        runner.run_tasks()
 
 
 class TokenTestCase(unittest.TestCase):