add minimal tests for dump class

unittest/python/python-pizza.py

@@ -120,6 +120,30 @@ class PythonDump(unittest.TestCase):
         self.lmp.command("dump 1 all custom 2 " + dumpfile + " id type mol q x y z vx vy vz")
         self.lmp.command("dump_modify 1 time yes units yes")
         self.lmp.command("run 4 post no")
+        d = dump.dump(dumpfile)
+        id1, id2 = d.minmax("id")
+        self.assertEqual(id1,1)
+        self.assertEqual(id2,29)
+        t = d.time()
+        self.assertEqual(len(t),3)
+        d.tselect.one(2,4)
+        index, time, flag = d.iterator(0)
+        self.assertEqual(index,1)
+        self.assertEqual(time,2)
+        self.assertEqual(flag,1)
+        index, time, flag = d.iterator(1)
+        self.assertEqual(index,2)
+        self.assertEqual(time,4)
+        self.assertEqual(flag,1)
+        index, time, flag = d.iterator(1)
+        self.assertEqual(index,0)
+        self.assertEqual(time,0)
+        self.assertEqual(flag,-1)
+
+        with self.assertRaises(Exception):
+          t = d.next()
+
+        os.remove(dumpfile)
 
 if __name__ == "__main__":
     unittest.main()