fix(parser,selection): correct None handling and Path type checks

- Ensure required argument validation treats only `None` as missing
  instead of falsy values (e.g., 0, False, empty string)
- Guard SelectionAction default resolution against `None` results
- Replace direct `type == Path` checks with `issubclass(..., Path)`
  for proper handling of Path subclasses across suggestions logic

Improves correctness in argument parsing and selection defaults,
aligning with Falyx’s explicit and predictable behavior goals.

falyx/action/selection_action.py

@@ -344,7 +344,7 @@ class SelectionAction(BaseAction):
                 selection = [
                     key
                     for key, sel in self.selections.items()
-                    if sel.value == maybe_result
+                    if sel.value == maybe_result and maybe_result is not None
                 ]
                 if selection:
                     effective_default = selection[0]

falyx/parser/command_argument_parser.py

@@ -1155,7 +1155,7 @@ class CommandArgumentParser:
         for spec in self._arguments:
             if spec.dest == "help" or spec.dest == "tldr":
                 continue
-            if spec.required and not result.get(spec.dest):
+            if spec.required and result.get(spec.dest) is None:
                 help_text = f" help: {spec.help}" if spec.help else ""
                 if (
                     spec.action == ArgumentAction.ACTION
@@ -1316,7 +1316,7 @@ class CommandArgumentParser:
                 for suggestion in arg.suggestions
                 if suggestion_filter(suggestion)
             ]
-        if arg.type is Path:
+        if issubclass(arg.type, Path):
             return self._suggest_paths(prefix if not cursor_at_end_of_token else ".")
         return []
 
@@ -1391,7 +1391,7 @@ class CommandArgumentParser:
                 ):
                     return []
                 return sorted(next_non_consumed_positional_arg.suggestions)
-            if next_non_consumed_positional_arg.type == Path:
+            if issubclass(next_non_consumed_positional_arg.type, Path):
                 if cursor_at_end_of_token:
                     return self._suggest_paths(".")
                 else:
@@ -1536,7 +1536,7 @@ class CommandArgumentParser:
                         if suggestion.startswith(last)
                     )
                 )
-            elif arg.type == Path and not cursor_at_end_of_token:
+            elif issubclass(arg.type, Path) and not cursor_at_end_of_token:
                 suggestions.extend(self._suggest_paths(last))
             elif last_keyword_state_in_args and not last_keyword_state_in_args.consumed:
                 suggestions.extend(

falyx/version.py

@@ -1 +1 @@
-__version__ = "0.1.86"
+__version__ = "0.1.87"

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "falyx"
-version = "0.1.86"
+version = "0.1.87"
 description = "Reliable and introspectable async CLI action framework."
 authors = ["Roland Thomas Jr <roland@rtj.dev>"]
 license = "MIT"