python: Add bhash tests

tests/test_bhash.py

@@ -0,0 +1,23 @@
+#!/usr/bin/env python3
+import passgeny.bhash
+import sys
+
+TEST_STRING = b'hello world'
+
+bh = passgeny.bhash.Bhash()
+
+bh.from_bytes(TEST_STRING)
+
+# Scan the string in reverse order (::-1) as bhash should use big endian arithmetics
+for c in TEST_STRING[::-1]:
+    hc = bh.modulo(256)
+    if hc != c:
+        raise Exception("Returned value is {}, expected {}".format(chr(hc), c))
+
+# This should throw an exception as we consumned all the bits in bhash
+try:
+    bh.modulo(2)
+except passgeny.bhash.BhashException as e:
+    print("Properly received exception: {}".format(e))
+else:
+    raise Exception("Did not receive BhashException.")