added test for bin with current implementation

myhdl/bin.py

@@ -42,8 +42,10 @@ def bin(num, width=0):
     """
     num = long(num)
     s = _int2bitstring(num)
-    pad = '0'
+    if width:
-    if num < 0:
+        pad = '0'
-        pad = '1'
+        if num < 0:
-    return (width - len(s)) * pad + s
+            pad = '1'
+        return (width - len(s)) * pad + s
+    return s 
 

myhdl/test_bin.py

@@ -0,0 +1,108 @@
+#  This file is part of the myhdl library, a Python package for using
+#  Python as a Hardware Description Language.
+#
+#  Copyright (C) 2003 Jan Decaluwe
+#
+#  The myhdl library is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public License as
+#  published by the Free Software Foundation; either version 2.1 of the
+#  License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful, but
+#  WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library; if not, write to the Free Software
+#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+""" Run the unit tests for bin """
+
+__author__ = "Jan Decaluwe <jan@jandecaluwe.com>"
+__revision__ = "$Revision$"
+__date__ = "$Date$"
+
+from __future__ import generators
+
+import random
+from random import randrange
+random.seed(1) # random, but deterministic
+
+import unittest
+from unittest import TestCase
+import sys
+from bin import bin
+
+def _int2bitstring(num):
+    if num == 0:
+        return '0'
+    if abs(num) == 1:
+        return '1'
+    return _int2bitstring(num // 2) + _int2bitstring(num % 2)
+
+def binref(num, width=0):
+    """Return a binary string representation.
+
+    num -- number to convert
+    Optional parameter:
+    width -- specifies the desired string (sign bit padding)
+    """
+    num = long(num)
+    s = _int2bitstring(num)
+    if width:
+        pad = '0'
+        if num < 0:
+            pad = '1'
+        return (width - len(s)) * pad + s
+    return s
+
+
+class TestBin(TestCase):
+
+    def testSmall(self):
+        for i in range(-65, 65):
+            self.assertEqual(bin(i), binref(i))
+                                     
+    def testSmallWidth(self):
+        for i in range(-65, 65):
+            w = randrange(1, 8)
+            self.assertEqual(bin(i, w), binref(i, w))
+
+    def testRandomInt(self):
+        for j in range(100):
+            i = randrange(-sys.maxint, sys.maxint)
+            self.assertEqual(bin(i), binref(i))
+            
+    def testRandomIntWidth(self):
+        for j in range(100):
+            w = randrange(1, 1000)
+            i = randrange(-sys.maxint, sys.maxint)
+            self.assertEqual(bin(i, w), binref(i, w))
+
+    def testRandomLong(self):
+        for j in range(100):
+            k = randrange(sys.maxint)
+            i = k + sys.maxint
+            self.assertEqual(bin(i), binref(i))
+            i = -k - sys.maxint
+            self.assertEqual(bin(i), binref(i))
+            
+    def testRandomLongWith(self):
+        for j in range(100):
+            w = randrange(1, 1000)
+            k = randrange(sys.maxint)
+            i = k + sys.maxint
+            self.assertEqual(bin(i, w), binref(i, w))
+            i = -k - sys.maxint
+            self.assertEqual(bin(i, w), binref(i, w))
+            
+
+            
+
+              
+
+       
+
+if __name__ == "__main__":
+    unittest.main()