fix: Parse complex, stringified annotations

Issue #159: #159

src/griffe/agents/nodes.py

@@ -5,7 +5,7 @@
 import enum
 import inspect
 import sys
-from ast import AST
+from ast import AST, PyCF_ONLY_AST
 from ast import Add as NodeAdd
 from ast import And as NodeAnd
 from ast import AnnAssign as NodeAnnAssign
@@ -636,10 +636,12 @@ def _get_call_annotation(node: NodeCall, parent: Module | Class) -> Expression:
     return Expression(_get_annotation(node.func, parent), "(", args, ")")
 
 
-def _get_constant_annotation(node: NodeConstant, parent: Module | Class) -> str | Name:
+def _get_constant_annotation(node: NodeConstant, parent: Module | Class) -> str | Name | Expression:
     if isinstance(node.value, str):
-        node.id = node.value  # type: ignore[attr-defined]  # fake node as Name
-        return _get_name_annotation(node, parent)  # type: ignore[arg-type]
+        # a string in an annotation is a stringified annotation: we parse it again
+        # literal strings must be wrapped in Literal[...] to be picked up as such
+        parsed = compile(node.value, mode="eval", filename="<string-annotation>", flags=PyCF_ONLY_AST, optimize=1)
+        return _get_annotation(parsed.body, parent=parent)  # type: ignore[attr-defined]
     return _get_literal_annotation(node, parent)
 
 

tests/test_nodes.py

@@ -224,3 +224,28 @@ def test_building_value_from_nodes(expression: str) -> None:
     expression = expression.replace(", ", ",")
 
     assert value == expression
+
+
+# https://github.com/mkdocstrings/griffe/issues/159
+def test_parsing_complex_string_annotations() -> None:
+    """Test parsing of complex, stringified annotations."""
+    with temporary_visited_module(
+        """
+        class ArgsKwargs:
+            def __init__(self, args: 'tuple[Any, ...]', kwargs: 'dict[str, Any] | None' = None) -> None:
+                ...
+
+            @property
+            def args(self) -> 'tuple[Any, ...]':
+                ...
+
+            @property
+            def kwargs(self) -> 'dict[str, Any] | None':
+                ...
+        """,
+    ) as module:
+        init_args_annotation = module["ArgsKwargs.__init__"].parameters["args"].annotation
+        assert isinstance(init_args_annotation, Expression)
+        assert init_args_annotation.is_tuple
+        kwargs_return_annotation = module["ArgsKwargs.kwargs"].annotation
+        assert isinstance(kwargs_return_annotation, Expression)