diff --git a/zulip/setup.py b/zulip/setup.py
index 1932074..42f179b 100755
--- a/zulip/setup.py
+++ b/zulip/setup.py
@@ -74,7 +74,7 @@ setuptools_info = dict(
 try:
     from setuptools import setup, find_packages
     package_info.update(setuptools_info)
-    package_info['packages'] = find_packages()
+    package_info['packages'] = find_packages(exclude=['tests'])
 
 except ImportError:
     from distutils.core import setup
diff --git a/zulip/tests/__init__.py b/zulip/tests/__init__.py
new file mode 100644
index 0000000..bb61062
--- /dev/null
+++ b/zulip/tests/__init__.py
@@ -0,0 +1,2 @@
+import pkgutil
+__path__ = pkgutil.extend_path(__path__, __name__)
diff --git a/zulip/tests/test_default_arguments.py b/zulip/tests/test_default_arguments.py
new file mode 100755
index 0000000..659b397
--- /dev/null
+++ b/zulip/tests/test_default_arguments.py
@@ -0,0 +1,45 @@
+from __future__ import absolute_import
+
+import argparse
+import os
+import six
+import unittest
+import zulip
+
+from unittest import TestCase
+
+if six.PY2:
+    from mock import patch
+else:
+    from unittest.mock import patch
+
+class TestDefaultArguments(TestCase):
+
+    def test_invalid_arguments(self):
+        parser = zulip.add_default_arguments(argparse.ArgumentParser(usage="lorem ipsum"))
+        with self.assertRaises(SystemExit) as cm, patch('sys.stderr', new=six.StringIO()) as mock_stderr:
+            parser.parse_args(['invalid argument'])
+        self.assertEqual(cm.exception.code, 2)
+        # Assert that invalid arguments exit with printing the full usage (non-standard behavior)
+        self.assertTrue(mock_stderr.getvalue().startswith("""usage: lorem ipsum
+
+optional arguments:
+  -h, --help            show this help message and exit
+
+Zulip API configuration:
+  --site ZULIP_SITE     Zulip server URI
+"""))
+
+    @patch('os.path.exists', return_value=False)
+    def test_config_path_with_tilde(self, mock_os_path_exists):
+        parser = zulip.add_default_arguments(argparse.ArgumentParser(usage="lorem ipsum"))
+        test_path = '~/zuliprc'
+        args = parser.parse_args(['--config-file', test_path])
+        with self.assertRaises(RuntimeError) as cm:
+            zulip.init_from_options(args)
+        expanded_test_path = os.path.abspath(os.path.expanduser(test_path))
+        self.assertEqual(str(cm.exception), 'api_key or email not specified and '
+                         'file {} does not exist'.format(expanded_test_path))
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/zulip_botserver/tests/__init__.py b/zulip_botserver/tests/__init__.py
index e69de29..bb61062 100644
--- a/zulip_botserver/tests/__init__.py
+++ b/zulip_botserver/tests/__init__.py
@@ -0,0 +1,2 @@
+import pkgutil
+__path__ = pkgutil.extend_path(__path__, __name__)