breaking change: A plain tuple type is no longer represented by a TupleTypeHint, but instead by a ClassTypeHint.

Author: NiklasRosenstein

.changelog/_unreleased.toml

@@ -0,0 +1,5 @@
+[[entries]]
+id = "a644d3b9-b9f7-4c9c-b240-2be2599e70d5"
+type = "breaking change"
+description = "A plain `tuple` type is no longer represented by a `TupleTypeHint`, but instead by a `ClassTypeHint`."
+author = "@NiklasRosenstein"

src/typeapi/typehint.py

@@ -89,7 +89,7 @@ def _make_wrapper(cls, hint: object, source: "Any | None") -> "TypeHint":
             return AnnotatedTypeHint(hint, source)
         elif isinstance(hint, TypeVar):
             return TypeVarTypeHint(hint, source)
-        elif origin == tuple or hint == tuple:
+        elif origin == tuple:
             return TupleTypeHint(hint, source)
 
         return ClassTypeHint(hint, source)
@@ -473,13 +473,17 @@ def expr(self) -> str:
 
 
 class TupleTypeHint(ClassTypeHint):
+    """
+    A special class to represent a type hint for a parameterized tuple. This class does not represent a plain tuple
+    type without parameterization.
+    """
+
     def __init__(self, hint: object, source: "Any | None") -> None:
         super().__init__(hint, source)
         if self._args == ((),):
             self._args = ()
         elif self._args == () and self._hint == tuple:
-            self._args = (Any, ...)
-            self._origin = tuple
+            raise ValueError(f"TupleTypeHint can only represent a parameterized tuple.")
         if ... in self._args:
             assert self._args[-1] == ..., "Tuple Ellipsis not as last arg"
             assert len(self._args) == 2, "Tuple with Ellipsis has more than two args"

src/typeapi/typehint_test.py

@@ -381,6 +381,10 @@ class B:
     assert hint.evaluate() == TypeHint(str)
 
 
+def test__TypeHint__tuple_evaluate() -> None:
+    assert TypeHint(tuple, source=tuple).evaluate() == TypeHint(tuple)
+
+
 def test__TypeHint__caching_same_named_type_hints() -> None:
     """
     This test ensures that type hint caching is stable if two different
@@ -435,13 +439,12 @@ def tupth(x: Any) -> TupleTypeHint:
 
 def test__TypeHint__native_tuple_type() -> None:
     hint = TypeHint(tuple)
-    assert isinstance(hint, TupleTypeHint), hint
-    assert len(hint) == 1
+    assert isinstance(hint, ClassTypeHint), hint
+    assert len(hint) == 0
     assert hint.hint == tuple
-    assert hint.origin == tuple
-    assert hint.args == (Any,)
+    assert hint.origin is None
+    assert hint.args == ()
     assert hint.parameters == ()
-    assert hint.repeated
     assert hint.bases == (object,)
 
     hint = TypeHint(Tuple[Any, ...])