Fixed Any being removed from a subscript that still contains other el…

…ements

Fixes #373.

docs/versionhistory.rst

@@ -3,6 +3,11 @@ Version history
 
 This library adheres to `Semantic Versioning 2.0 <https://semver.org/#semantic-versioning-200>`_.
 
+**UNRELEASED**
+
+- Fixed ``Any`` being removed from a subscript that still contains other elements
+  (`#373 <https://github.com/agronholm/typeguard/issues/373>`_
+
 **4.1.1** (2023-08-16)
 
 - Fixed ``suppress_type_checks()`` causing annotated variable assignments to always

src/typeguard/_transformer.py

@@ -349,15 +349,21 @@ class AnnotationTransformer(NodeTransformer):
     def __init__(self, transformer: TypeguardTransformer):
         self.transformer = transformer
         self._memo = transformer._memo
+        self._level = 0
 
     def visit(self, node: AST) -> Any:
+        self._level += 1
         new_node = super().visit(node)
+        self._level -= 1
+
         if isinstance(new_node, Expression) and not hasattr(new_node, "body"):
             return None
 
         # Return None if this new node matches a variation of typing.Any
-        if isinstance(new_node, expr) and self._memo.name_matches(
-            new_node, *anytype_names
+        if (
+            self._level == 0
+            and isinstance(new_node, expr)
+            and self._memo.name_matches(new_node, *anytype_names)
         ):
             return None
 
@@ -373,9 +379,11 @@ def visit_BinOp(self, node: BinOp) -> Any:
         self.generic_visit(node)
 
         if isinstance(node.op, BitOr):
-            # If either side of the operation resolved to None, return None
-            if not hasattr(node, "left") or not hasattr(node, "right"):
-                return None
+            # Return Any if either side is Any
+            if self._memo.name_matches(node.left, *anytype_names):
+                return node.left
+            elif self._memo.name_matches(node.right, *anytype_names):
+                return node.right
 
             if sys.version_info < (3, 10):
                 union_name = self.transformer._get_import("typing", "Union")

tests/test_transformer.py

@@ -398,6 +398,35 @@ def foo(x, y: Any | None) -> Any | None:
     )
 
 
+def test_any_in_nested_dict() -> None:
+    # Regression test for #373
+    node = parse(
+        dedent(
+            """
+            from typing import Any
+
+            def foo(x: dict[str, dict[str, Any]]) -> None:
+                pass
+            """
+        )
+    )
+    TypeguardTransformer().visit(node)
+    assert (
+        unparse(node)
+        == dedent(
+            """
+            from typeguard import TypeCheckMemo
+            from typeguard._functions import check_argument_types
+            from typing import Any
+
+            def foo(x: dict[str, dict[str, Any]]) -> None:
+                memo = TypeCheckMemo(globals(), locals())
+                check_argument_types('foo', {'x': (x, dict[str, dict[str, Any]])}, memo)
+            """
+        ).strip()
+    )
+
+
 def test_avoid_global_names() -> None:
     node = parse(
         dedent(