[#49] trits_from_int now defaults to pad=1.

Author: todofixthis

iota/types.py

@@ -34,7 +34,7 @@
 TrytesCompatible = Union[AnyStr, bytearray, 'TryteString']
 
 
-def trits_from_int(n, pad=None):
+def trits_from_int(n, pad=1):
   # type: (int, Optional[int]) -> List[int]
   """
   Returns a trit representation of an integer value.
@@ -60,7 +60,7 @@ def trits_from_int(n, pad=None):
       quotient  += 1
       remainder = -1
 
-    trits = [remainder] + trits_from_int(quotient)
+    trits = [remainder] + trits_from_int(quotient, pad=0)
 
   if pad:
     trits += [0] * max(0, pad - len(trits))

test/types_test.py

@@ -6,8 +6,31 @@
 
 from six import binary_type, text_type
 
-from iota import Address, AddressChecksum, Hash, Tag, TryteString, TrytesCodec, \
-  TrytesDecodeError
+from iota import Address, AddressChecksum, Hash, Tag, TryteString, \
+  TrytesCodec, TrytesDecodeError, trits_from_int
+
+
+class TritsFromIntTestCase(TestCase):
+  """
+  Explicit unit tests for :py:func:`trits_from_int`.
+
+  Note that this function is used internally by many different classes
+  and functions, so we still have good coverage even though this
+  particular test case has limited scope.
+  """
+  def test_zero(self):
+    """
+    Zero is represented as ``[0]`` by default.
+
+    https://github.com/iotaledger/iota.lib.py/issues/49
+    """
+    self.assertEqual(trits_from_int(0), [0])
+
+  def test_zero_unpadded(self):
+    """
+    Converting zero to trits, without padding.
+    """
+    self.assertEqual(trits_from_int(0, pad=None), [])
 
 
 # noinspection SpellCheckingInspection