Accept none value in build raw for to address

tests/test_address.py

@@ -0,0 +1,35 @@
+import unittest
+
+from chainlib.eth.address import (
+        is_address,
+        is_checksum_address,
+        to_checksum,
+        )
+
+from tests.base import TestBase
+
+
+class TestChain(TestBase):
+
+    def test_chain_spec(self):
+        checksum_address = '0xEb3907eCad74a0013c259D5874AE7f22DcBcC95C'
+        plain_address = checksum_address.lower()
+
+        self.assertEqual(checksum_address, to_checksum(checksum_address))
+
+        self.assertTrue(is_address(plain_address))
+        self.assertFalse(is_checksum_address(plain_address))
+        self.assertTrue(is_checksum_address(checksum_address))
+
+        self.assertFalse(is_address(plain_address + "00"))
+        self.assertFalse(is_address(plain_address[:len(plain_address)-2]))
+
+        with self.assertRaises(ValueError):
+            to_checksum(plain_address + "00")
+
+        with self.assertRaises(ValueError):
+            to_checksum(plain_address[:len(plain_address)-2])
+
+
+if __name__ == '__main__':
+    unittest.main()