fix: fix edge case on forward unresolveable type

Author: KelvinChung2000

cmd2/annotated.py

@@ -1726,8 +1726,16 @@ def _resolve_parameters(
     # cmd2_handler, so it must exist.  Here so it also fires when the function has zero parameters.
     if base_command and "cmd2_handler" not in sig.parameters:
         raise TypeError(f"with_annotated(base_command=True) requires a 'cmd2_handler' parameter in {func.__qualname__}")
+    # Resolve hints only for the parameters that become arguments
+    ignored = {next(iter(sig.parameters), None), *skip_params}
+    ignored.discard(None)
+    relevant_annotations = {name: ann for name, ann in getattr(func, "__annotations__", {}).items() if name not in ignored}
     try:
-        hints = get_type_hints(func, include_extras=True)
+        hints = get_type_hints(
+            types.SimpleNamespace(__annotations__=relevant_annotations),
+            globalns=getattr(func, "__globals__", {}),
+            include_extras=True,
+        )
     except (NameError, AttributeError, TypeError) as exc:
         raise TypeError(
             f"Failed to resolve type hints for {func.__qualname__}. Ensure all annotations use valid, importable types."

tests/test_annotated.py

@@ -631,6 +631,24 @@ def do_broken(self, name: "NonExistentType"):  # noqa: F821
         with pytest.raises(TypeError, match="Failed to resolve type hints"):
             build_parser_from_function(do_broken)
 
+    def test_unresolvable_hint_on_ignored_self_is_tolerated(self) -> None:
+        """An unresolvable annotation on the bound parameter (self/cls) must not abort
+        parser generation, since it is never turned into an argument. This happens when
+        ``self`` is annotated with a forward reference that is only importable under
+        ``TYPE_CHECKING``.
+        """
+
+        def do_cmd(self: "UnimportableCmd", name: str, count: int = 1):  # noqa: F821
+            pass
+
+        # Without the lenient retry this raises "Failed to resolve type hints".
+        parser = build_parser_from_function(do_cmd)
+        dests = {action.dest for action in parser._actions if action.dest != "help"}
+        assert dests == {"name", "count"}
+        ns = parser.parse_args(["alice"])
+        assert ns.name == "alice"
+        assert ns.count == 1
+
     def test_validate_base_command_type_hints_failure_raises(self) -> None:
         """Base-command validation should raise, not swallow, type hint failures."""
         from cmd2.annotated import _resolve_parameters