Add eval_str to inspect.signature

tests/test_annotated.py

@@ -21,6 +21,22 @@ def cmd(val: Annotated[int, typer.Argument()] = 0):
     assert "hello 42" in result.output
 
 
+def test_annotated_argument_in_string_type_with_default():
+    app = typer.Typer()
+
+    @app.command()
+    def cmd(val: "Annotated[int, typer.Argument()]" = 0):
+        print(f"hello {val}")
+
+    result = runner.invoke(app)
+    assert result.exit_code == 0, result.output
+    assert "hello 0" in result.output
+
+    result = runner.invoke(app, ["42"])
+    assert result.exit_code == 0, result.output
+    assert "hello 42" in result.output
+
+
 def test_annotated_argument_with_default_factory():
     app = typer.Typer()
 

typer/utils.py

@@ -106,7 +106,7 @@ def _split_annotation_from_typer_annotations(
 
 
 def get_params_from_function(func: Callable[..., Any]) -> Dict[str, ParamMeta]:
-    signature = inspect.signature(func)
+    signature = inspect.signature(func, eval_str=True)
     type_hints = get_type_hints(func)
     params = {}
     for param in signature.parameters.values():