created unittest for type_helpers; added is_unicode

diff --git a/test/type_helper_unittest.py b/test/type_helper_unittest.py
new file mode 100644 (file)
index 0000000..af89fdf
--- /dev/null
+++ b/test/type_helper_unittest.py
@@ -0,0 +1,67 @@
+""" type_helper_unittest.py: unit tests for type_helpers
+
+Tests classes and functions in type_helpers
+
+Should be run from python2 and python3!
+
+For help see :py:mod:`unittest`
+
+.. codeauthor:: Christian Herdtweck, christian.herdtweck@intra2net.com
+"""
+
+import unittest
+
+from type_helpers import is_unicode, isstr
+from sys import version_info
+
+
+is_py2 = version_info.major == 2
+
+class TypeHelperTester(unittest.TestCase):
+
+    def test_is_py2_or_py3(self):
+        """ test that python version is 2 or 3
+
+        when implementing type_helpers, there was no py4 and no idea what it
+        might be like. Also will probably fail for python v1
+        """
+        self.assertIn(version_info.major, (2, 3))
+
+    def test_is_unicode(self):
+        """ tests function is_unicode """
+
+        self.assertFalse(is_unicode(1))
+        self.assertFalse(is_unicode([]))
+        self.assertFalse(is_unicode(unittest.TestCase))
+        self.assertFalse(is_unicode(type(unittest.TestCase)))
+
+        if is_py2:
+            self.assertTrue(is_unicode(u'bla'))
+            self.assertTrue(eval("is_unicode(ur'bla')"))  # not allowed in py3!
+            self.assertFalse(is_unicode('bla'))
+            self.assertFalse(is_unicode(r'bla'))
+        else:
+            self.assertTrue(is_unicode('bla'))
+            self.assertTrue(is_unicode(r'bla'))
+            self.assertFalse(is_unicode(b'bla'))
+            self.assertFalse(is_unicode(br'bla'))
+
+    def test_isstr(self):
+        """ test function isstr """
+
+        tests = [
+            ('abc', True), (u'abc', True), (r'abc', True),
+            (1, False), (['a', 'b', 'c'], False), (('a', 'b', 'c'), False)]
+        if not is_py2:
+            tests.append((b'abc', False))  # b'' does not exist in py2
+
+        for test_var, expected_result in tests:
+            self.assertEqual(isstr(test_var), expected_result,
+                             'isstr of var {0} (which is of type {1}) returned'
+                             '{2} but expected {3}!'
+                             .format(test_var, type(test_var), isstr(test_var),
+                                     expected_result))
+
+
+if __name__ == '__main__':
+    unittest.main()

diff --git a/type_helpers.py b/type_helpers.py
index c44a873..18fbec9 100644 (file)
--- a/type_helpers.py
+++ b/type_helpers.py
@@ -19,6 +19,8 @@
 """
 Helpers for type checking and conversion, like isstr(x), is_file_obj(x)
 
+Provides abstraction from difference between PY2 and PY3
+
 .. codeauthor:: Christian Herdtweck, christian.herdtweck@intra2net.com
 """
 
@@ -60,6 +62,19 @@ def is_str_or_byte(var):
         return isinstance(var, basestring)
 
 
+def is_unicode(var):
+    """ returns true for unicode strings
+
+    py2: return True for type unicode but not type str
+    py3: return True for type str but not type bytes
+    """
+
+    if PY2:
+        return isinstance(var, unicode)
+    else:
+        return isinstance(var, str)
+
+
 def is_file_obj(var):
     """ determines whether given input is the result of 'open(file_name)'
 
@@ -69,26 +84,6 @@ def is_file_obj(var):
     return isinstance(var, IOBase)
 
 
-def test_isstr():
-    """ test function isstr
-
-    TODO: should probably be moved to some unittest or so ...
-    """
-
-    tests = [
-        ('abc', True), (u'abc', True), (r'abc', True),
-        (1, False), (['a', 'b', 'c'], False), (('a', 'b', 'c'), False)]
-    if PY3:
-        tests.append((b'abc', False))  # b'' does not exist in py2
-
-    for test_var, expected_result in tests:
-        assert isstr(test_var) == expected_result, 'isstr of var {0} ' \
-            '(which is of type {1}) returned {2} but expected {3}!'.format(
-                test_var, type(test_var), isstr(test_var), expected_result)
-    print('all string tests finished successfully')
-# end: test_isstr
-
-
 def main():
     """ Main function, called when running file as script
 
@@ -98,8 +93,6 @@ def main():
         print('is python3')
     else:
         print('is python2')
-
-    # test_isstr()
 # end: function main