raise exceptions when walking through object path

if we're given path a.b.c and the existing object is:
a:
  b:
   - item1
raise an exception due to unexpected objects found while traversing the path (ie. b is a list, not a dict)

also, add_entry assumes new dicts for each sub element when creating elements besides the final assignment value.
doing something like a.b.c[0] = 12 where 'c' doesn't exist raises an exception

add test cases to cover:
access path that differs from existing object
create new objects with an embedded list in the path
create new object with a list at the end (define the end list in the passed in 'value' to avoid this exception)

3 files changed, 38 insertions, 5 deletions

diff --git a/roles/lib_utils/library/yedit.py b/roles/lib_utils/library/yedit.py
index b1d9d6869..a2ae6b4f6 100644
--- a/roles/lib_utils/library/yedit.py
+++ b/roles/lib_utils/library/yedit.py
@@ -311,7 +311,8 @@ class Yedit(object):
                     continue
 
                 elif data and not isinstance(data, dict):
-                    return None
+                    raise YeditException("Unexpected item type found while going through key " +
+                                         "path: {} (at key: {})".format(key, dict_key))
 
                 data[dict_key] = {}
                 data = data[dict_key]
@@ -320,7 +321,7 @@ class Yedit(object):
                   int(arr_ind) <= len(data) - 1):
                 data = data[int(arr_ind)]
             else:
-                return None
+                raise YeditException("Unexpected item type found while going through key path: {}".format(key))
 
         if key == '':
             data = item
@@ -334,6 +335,12 @@ class Yedit(object):
         elif key_indexes[-1][1] and isinstance(data, dict):
             data[key_indexes[-1][1]] = item
 
+        # didn't add/update to an existing list, nor add/update key to a dict
+        # so we must have been provided some syntax like a.b.c[<int>] = "data" for a
+        # non-existent array
+        else:
+            raise YeditException("Error adding to object at path: {}".format(key))
+
         return data
 
     @staticmethod
diff --git a/roles/lib_utils/src/class/yedit.py b/roles/lib_utils/src/class/yedit.py
index 74ee52fe3..533665db2 100644
--- a/roles/lib_utils/src/class/yedit.py
+++ b/roles/lib_utils/src/class/yedit.py
@@ -125,7 +125,8 @@ class Yedit(object):
                     continue
 
                 elif data and not isinstance(data, dict):
-                    return None
+                    raise YeditException("Unexpected item type found while going through key " +
+                                         "path: {} (at key: {})".format(key, dict_key))
 
                 data[dict_key] = {}
                 data = data[dict_key]
@@ -134,7 +135,7 @@ class Yedit(object):
                   int(arr_ind) <= len(data) - 1):
                 data = data[int(arr_ind)]
             else:
-                return None
+                raise YeditException("Unexpected item type found while going through key path: {}".format(key))
 
         if key == '':
             data = item
@@ -148,6 +149,12 @@ class Yedit(object):
         elif key_indexes[-1][1] and isinstance(data, dict):
             data[key_indexes[-1][1]] = item
 
+        # didn't add/update to an existing list, nor add/update key to a dict
+        # so we must have been provided some syntax like a.b.c[<int>] = "data" for a
+        # non-existent array
+        else:
+            raise YeditException("Error adding to object at path: {}".format(key))
+
         return data
 
     @staticmethod
diff --git a/roles/lib_utils/src/test/unit/test_yedit.py b/roles/lib_utils/src/test/unit/test_yedit.py
index ed07ac96e..ce5e027a7 100755
--- a/roles/lib_utils/src/test/unit/test_yedit.py
+++ b/roles/lib_utils/src/test/unit/test_yedit.py
@@ -23,7 +23,7 @@ import unittest
 yedit_path = os.path.join('/'.join(os.path.realpath(__file__).split('/')[:-4]), 'library')  # noqa: E501
 sys.path.insert(0, yedit_path)
 
-from yedit import Yedit  # noqa: E402
+from yedit import Yedit, YeditException  # noqa: E402
 
 # pylint: disable=too-many-public-methods
 # Silly pylint, moar tests!
@@ -200,6 +200,7 @@ class YeditTest(unittest.TestCase):
         yed.append('x:y:z', [5, 6])
         yed.append('x:y:z', [5, 6])
         self.assertTrue(yed.get('x:y:z') == [1, 2, 3, [5, 6], [5, 6]])
+        # pylint: disable=maybe-no-member
         self.assertTrue(2 == yed.get('x:y:z').count([5, 6]))
         self.assertFalse(yed.exists('x:y:z', 4))
 
@@ -268,6 +269,24 @@ class YeditTest(unittest.TestCase):
         yed.pop('a#b', 'c')
         self.assertTrue({'a': {'b': {'d': 2}}} == yed.yaml_dict)
 
+    def test_accessing_path_with_unexpected_objects(self):
+        '''test providing source path objects that differ from current object state'''
+        yed = Yedit(content={'a': {'b': {'c': ['d', 'e']}}})
+        with self.assertRaises(YeditException):
+            yed.put('a.b.c.d', 'x')
+
+    def test_creating_new_objects_with_embedded_list(self):
+        '''test creating new objects with an embedded list in the creation path'''
+        yed = Yedit(content={'a': {'b': 12}})
+        with self.assertRaises(YeditException):
+            yed.put('new.stuff[0].here', 'value')
+
+    def test_creating_new_objects_with_trailing_list(self):
+        '''test creating new object(s) where the final piece is a list'''
+        yed = Yedit(content={'a': {'b': 12}})
+        with self.assertRaises(YeditException):
+            yed.put('new.stuff.here[0]', 'item')
+
     def tearDown(self):
         '''TearDown method'''
         os.unlink(YeditTest.filename)