fix: allow path to be a list of strings, integers or any other hashab…

…les (#497)

voluptuous/error.py

@@ -19,7 +19,13 @@ class Invalid(Error):
 
     """
 
-    def __init__(self, message: str, path: typing.Optional[typing.List[str]] = None, error_message: typing.Optional[str] = None, error_type: typing.Optional[str] = None) -> None:
+    def __init__(
+        self,
+        message: str,
+        path: typing.Optional[typing.List[typing.Hashable]] = None,
+        error_message: typing.Optional[str] = None,
+        error_type: typing.Optional[str] = None
+    ) -> None:
         Error.__init__(self, message)
         self._path = path or []
         self._error_message = error_message or message
@@ -30,7 +36,7 @@ def msg(self) -> str:
         return self.args[0]
 
     @property
-    def path(self) -> typing.List[str]:
+    def path(self) -> typing.List[typing.Hashable]:
         return self._path
 
     @property
@@ -45,7 +51,7 @@ def __str__(self) -> str:
             output += ' for ' + self.error_type
         return output + path
 
-    def prepend(self, path: typing.List[str]) -> None:
+    def prepend(self, path: typing.List[typing.Hashable]) -> None:
         self._path = path + self.path
 
 
@@ -61,7 +67,7 @@ def msg(self) -> str:
         return self.errors[0].msg
 
     @property
-    def path(self) -> typing.List[str]:
+    def path(self) -> typing.List[typing.Hashable]:
         return self.errors[0].path
 
     @property
@@ -74,7 +80,7 @@ def add(self, error: Invalid) -> None:
     def __str__(self) -> str:
         return str(self.errors[0])
 
-    def prepend(self, path: typing.List[str]) -> None:
+    def prepend(self, path: typing.List[typing.Hashable]) -> None:
         for error in self.errors:
             error.prepend(path)
 

voluptuous/humanize.py

@@ -7,10 +7,7 @@
 MAX_VALIDATION_ERROR_ITEM_LENGTH = 500
 
 
-IndexT = typing.TypeVar("IndexT")
-
-
-def _nested_getitem(data: typing.Dict[IndexT, typing.Any], path: typing.List[IndexT]) -> typing.Optional[typing.Any]:
+def _nested_getitem(data: typing.Any, path: typing.List[typing.Hashable]) -> typing.Optional[typing.Any]:
     for item_index in path:
         try:
             data = data[item_index]

voluptuous/tests/tests.py

@@ -1329,6 +1329,76 @@ def test_match_error_has_path():
         assert False, "Did not raise MatchInvalid"
 
 
+def test_path_with_string():
+    """Most common dict use with strings as keys"""
+    s = Schema({'string_key': int})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({'string_key': 'str'})
+    assert ctx.value.errors[0].path == ['string_key']
+
+
+def test_path_with_list_index():
+    """Position of the offending list index included in path as int"""
+    s = Schema({'string_key': [int]})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({'string_key': [123, 'should be int']})
+    assert ctx.value.errors[0].path == ['string_key', 1]
+
+
+def test_path_with_tuple_index():
+    """Position of the offending tuple index included in path as int"""
+    s = Schema({'string_key': (int,)})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({'string_key': (123, 'should be int')})
+    assert ctx.value.errors[0].path == ['string_key', 1]
+
+
+def test_path_with_integer_dict_key():
+    """Not obvious case with dict having not strings, but integers as keys"""
+    s = Schema({1337: int})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({1337: 'should be int'})
+    assert ctx.value.errors[0].path == [1337]
+
+
+def test_path_with_float_dict_key():
+    """Not obvious case with dict having not strings, but floats as keys"""
+    s = Schema({13.37: int})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({13.37: 'should be int'})
+    assert ctx.value.errors[0].path == [13.37]
+
+
+def test_path_with_tuple_dict_key():
+    """Not obvious case with dict having not strings, but tuples as keys"""
+    s = Schema({('fancy', 'key'): int})
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({('fancy', 'key'): 'should be int'})
+    assert ctx.value.errors[0].path == [('fancy', 'key')]
+
+
+def test_path_with_arbitrary_hashable_dict_key():
+    """Not obvious case with dict having not strings, but arbitrary hashable objects as keys"""
+
+    class HashableObjectWhichWillBeKeyInDict:
+        def __hash__(self):
+            return 1337  # dummy hash, used only for illustration
+
+    s = Schema({HashableObjectWhichWillBeKeyInDict: [int]})
+
+    hashable_obj_provided_in_input = HashableObjectWhichWillBeKeyInDict()
+
+    with pytest.raises(MultipleInvalid) as ctx:
+        s({hashable_obj_provided_in_input: [0, 1, 'should be int']})
+    assert ctx.value.errors[0].path == [hashable_obj_provided_in_input, 2]
+
+
 def test_self_any():
     schema = Schema({"number": int,
                      "follow": Any(Self, "stop")})

voluptuous/validators.py

@@ -224,7 +224,7 @@ def __voluptuous_compile__(self, schema: Schema) -> typing.Callable:
         schema.required = old_required
         return self._run
 
-    def _run(self, path: typing.List[str], value):
+    def _run(self, path: typing.List[typing.Hashable], value):
         if self.discriminant is not None:
             self._compiled = [
                 self.schema._compile(v)
@@ -243,7 +243,7 @@ def __repr__(self):
             self.msg
         )
 
-    def _exec(self, funcs: typing.Iterable, v, path: typing.Optional[typing.List[str]] = None):
+    def _exec(self, funcs: typing.Iterable, v, path: typing.Optional[typing.List[typing.Hashable]] = None):
         raise NotImplementedError()