From ce20f5b6875e8d04d57682408e084e182d8288cd Mon Sep 17 00:00:00 2001
From: Philipp Gesang <philipp.gesang@intra2net.com>
Date: Mon, 5 Nov 2018 09:58:43 +0100
Subject: [PATCH] validate SimpleCnf inputs

The cnfvar functions cannot handle ``tuple'' inputs since the
inputs are variable length. Make simple_cnf pass a list instead
and reject non-list inputs in the ctor.
---
 src/simple_cnf.py       |   12 +++++++-----
 test/test_simple_cnf.py |   24 ++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/simple_cnf.py b/src/simple_cnf.py
index 96dc5b2..23b5ca4 100644
--- a/src/simple_cnf.py
+++ b/src/simple_cnf.py
@@ -237,14 +237,16 @@ class SimpleCnf(object):
         Creates a simple configuration.
 
         :param cnf: initial set of conf var data (default: None = empty conf)
-        :type cnf: list or tuple or anything that :py:func:`get_cnf` can read
+        :type cnf: list or anything that :py:func:`get_cnf` can read
         """
-        if isinstance(cnf, (list, tuple)):
+        if cnf is None:
+            self.__cnfvars = []
+        elif isinstance(cnf, list):
             self.__cnfvars = cnf
-        elif cnf is not None:
+        elif isinstance(cnf, dict):
             self.__cnfvars = get_cnf(cnf)
         else:
-            self.__cnfvars = []
+            raise InvalidCnf ("cannot handle %s type inputs" % type (cnf))
 
     def _find_new_number(self, cnf_vars):
         """Recursive helper function to find new unique (line) number."""
@@ -579,7 +581,7 @@ class SimpleCnf(object):
         else:
             line_test = lambda test_val: test_val['number'] == line
 
-        return SimpleCnf(tuple(entry for entry in self.__cnfvars
+        return SimpleCnf(list(entry for entry in self.__cnfvars
                                if name_test(entry) and value_test(entry)
                                and instance_test(entry) and line_test(entry)))
 
diff --git a/test/test_simple_cnf.py b/test/test_simple_cnf.py
index 92ef9e7..bdc9883 100755
--- a/test/test_simple_cnf.py
+++ b/test/test_simple_cnf.py
@@ -28,6 +28,7 @@ import os
 import sys
 
 from src.simple_cnf import SimpleCnf
+from src.simple_cnf import InvalidCnf
 
 TEST_SET = """
 1  USER,1: "admin"
@@ -163,6 +164,29 @@ class SimpleCnfTest(unittest.TestCase):
 
     # tests
 
+    def test_ctor_ok (self):
+        """
+        Test initializer :py:meth:`SimpleCnf.__init__` must succeed on sane
+        inputs.
+        """
+        self.assertNotEqual (SimpleCnf ({"cnf": []}), None)
+        self.assertNotEqual (SimpleCnf ([]), None)
+        self.assertNotEqual (SimpleCnf (), None)
+
+    def test_ctor_fail (self):
+        """
+        Test initializer :py:meth:`SimpleCnf.__init__` must reject inputs that
+        ``cnfvar.py`` does not handle.
+        """
+        with self.assertRaises (InvalidCnf):
+            _void = SimpleCnf (b"junk")
+        with self.assertRaises (InvalidCnf):
+            _void = SimpleCnf (42)
+        with self.assertRaises (InvalidCnf):
+            _void = SimpleCnf (tuple ([1701, 1337]))
+        with self.assertRaises (InvalidCnf):
+            _void = SimpleCnf (set (["one", "two"]))
+
     def test_eq(self):
         """ test method :py:meth:`SimpleCnf.__eq__` """
         self.assertEqual(self.cnf[61], self.cnf[61])
-- 
1.7.1