Require exact value types when validating Literal fields

CHANGELOG.md

@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-...
+### Fixed
+
+- Require matching value types when checking `Literal` fields, distinguishing equal boolean, integer, and enum values.
 
 ## [1.9.2] - 2025-02-05
 

dacite/types.py

@@ -171,7 +171,7 @@ def is_instance(value: Any, type_: Type) -> bool:
     if is_new_type(type_):
         return is_instance(value, extract_new_type(type_))
     if is_literal(type_):
-        return value in extract_generic(type_)
+        return any(type(value) is type(literal) and value == literal for literal in extract_generic(type_))
     if is_init_var(type_):
         return is_instance(value, extract_init_var(type_))
     if is_type_generic(type_):

tests/core/test_literal.py

@@ -1,4 +1,5 @@
 from dataclasses import dataclass
+from enum import IntEnum
 from typing import Optional
 
 import pytest
@@ -57,3 +58,26 @@ class X:
     result = from_dict(X, {"l": "A"})
 
     assert result == X(l="A")
+
+
+class Number(IntEnum):
+    ONE = 1
+
+
+@literal_support
+@pytest.mark.parametrize(
+    "literal, value", [(1, True), (True, 1), (0, False), (False, 0), (1, 1.0), (Number.ONE, 1), (1, Number.ONE)]
+)
+def test_from_dict_with_equal_literal_of_wrong_type(literal, value):
+    from typing import Literal
+
+    @dataclass
+    class X:
+        l: Literal[literal]
+
+    with pytest.raises(WrongTypeError):
+        from_dict(X, {"l": value})
+
+    result = from_dict(X, {"l": literal})
+    assert result.l == literal
+    assert type(result.l) is type(literal)