Add test for cookiecutter substitution

tests/test_cookiecutter_substitution.py

@@ -0,0 +1,41 @@
+import os
+import re
+import shutil
+import unittest
+from os.path import dirname, exists, join
+
+from cookiecutter.main import cookiecutter
+
+
+class TestCookiecutterSubstitution(unittest.TestCase):
+    """Test that all cookiecutter instances are substituted"""
+
+    cookiecutter(dirname(dirname(__file__)), no_input=True)
+
+    destpath = join(dirname(dirname(__file__)), 'project_name')
+
+    def tearDown(self):
+        if exists(self.destpath):
+            shutil.rmtree(self.destpath)
+
+    def test_all_cookiecutter_instances_are_substituted(self):
+        # Build a list containing absolute paths to the generated files
+        paths = [os.path.join(dirpath, file_path)
+                 for dirpath, subdirs, files in os.walk(self.destpath)
+                 for file_path in files]
+
+        # Construct the cookiecutter search pattern
+        pattern = "{{(\s?cookiecutter)[.](.*?)}}"
+        re_obj = re.compile(pattern)
+
+        # Assert that no match is found in any of the files
+        for path in paths:
+            for line in open(path, 'r'):
+                match = re_obj.search(line)
+                self.assertIsNone(
+                    match,
+                    "cookiecutter variable not replaced in {}".format(path))
+
+
+if __name__ == '__main__':
+    unittest.main()