Start adding some tests

Improve the fixed_version function
Better binary search parameter return values

setup.py

@@ -1,4 +1,4 @@
-from setuptools import setup
+from setuptools import setup, find_packages
 from os import path
 from zttf import __version__
 
@@ -32,5 +32,6 @@ setup(
         'Programming Language :: Python :: 3.4',
     ],
     keywords='fonts truetype ttf',
-    packages=['zttf']
-)
+    packages=find_packages(exclude=['tests']),
+    test_suite='tests'
+)

tests/__init__.py

@@ -0,0 +1 @@
+__author__ = 'david'

tests/utils_test.py

@@ -0,0 +1,23 @@
+import unittest
+
+from zttf.utils import fixed_version, binary_search_parameters
+
+
+class TestUtils(unittest.TestCase):
+    def test_fixed_version(self):
+        cases = [
+            (0x00005000, 0.5),
+            (0x00010000, 1.0),
+            (0x00035000, 3.5),
+            (0x00105000, 10.5)
+        ]
+        for case in cases:
+            self.assertEqual(fixed_version(case[0]), case[1])
+
+    def test_binary_parameters(self):
+        cases = {
+            39: (5, 64, 14),
+            10: (3, 16, 4)
+        }
+        for n, result in cases.items():
+            self.assertEqual(binary_search_parameters(n), result)

zttf/utils.py

@@ -91,26 +91,22 @@ def fixed_version(num):
     :param num: fixed 16:16 floating point number as a 32-bit unsigned integer
     :return: version number (float)
     """
-    if num == 0x00005000:
-        return 0.5
-    elif num == 0x00010000:
-        return 1.0
-    elif num == 0x00020000:
-        return 2.0
-    elif num == 0x00025000:
-        return 2.5
-    elif num == 0x00030000:
-        return 3.0
-    return num
+    return float("{:04x}.{:04x}".format(num >> 16, num & 0x0000ffff))
 
 
 def binary_search_parameters(length):
-    search_range = 1
-    entry_selector = 0
+    """ The TTF specification has several places that require binary search
+        parameters. For an example look at the CMAP Format 4 table.
+    :param length: The range over which the search will be performed.
+    :return: The 3 parameters required.
+    """
+    search_range = 2
+    entry_selector = 1
     while search_range * 2 <= length:
         search_range *= 2
         entry_selector += 1
-    return entry_selector, search_range, length - search_range
+    search_range *= 2
+    return entry_selector, search_range, 2 * length - search_range
 
 
 class Range: