tomli.loads: Raise TypeError not AttributeError. Improve message (#229)

Author: hukkin

src/tomli/_parser.py

@@ -71,7 +71,12 @@ def loads(__s: str, *, parse_float: ParseFloat = float) -> dict[str, Any]:  # no
 
     # The spec allows converting "\r\n" to "\n", even in string
     # literals. Let's do so to simplify parsing.
-    src = __s.replace("\r\n", "\n")
+    try:
+        src = __s.replace("\r\n", "\n")
+    except (AttributeError, TypeError):
+        raise TypeError(
+            f"Expected str object, not '{type(__s).__qualname__}'"
+        ) from None
     pos = 0
     out = Output(NestedDict(), Flags())
     header: Key = ()

tests/test_error.py

@@ -39,6 +39,15 @@ def test_invalid_char_quotes(self):
             tomllib.loads("v = '\n'")
         self.assertTrue(" '\\n' " in str(exc_info.exception))
 
+    def test_type_error(self):
+        with self.assertRaises(TypeError) as exc_info:
+            tomllib.loads(b"v = 1")  # type: ignore[arg-type]
+        self.assertEqual(str(exc_info.exception), "Expected str object, not 'bytes'")
+
+        with self.assertRaises(TypeError) as exc_info:
+            tomllib.loads(False)  # type: ignore[arg-type]
+        self.assertEqual(str(exc_info.exception), "Expected str object, not 'bool'")
+
     def test_module_name(self):
         self.assertEqual(tomllib.TOMLDecodeError().__module__, tomllib.__name__)