Fixes CLI help text for function types (#370)

pydantic_settings/sources.py

@@ -1,5 +1,6 @@
 from __future__ import annotations as _annotations
 
+import inspect
 import json
 import os
 import re
@@ -17,7 +18,6 @@
 from enum import Enum
 from pathlib import Path
 from textwrap import dedent
-from types import FunctionType
 from typing import (
     TYPE_CHECKING,
     Any,
@@ -1718,8 +1718,9 @@ def _metavar_format_choices(self, args: list[str], obj_qualname: str | None = No
     def _metavar_format_recurse(self, obj: Any) -> str:
         """Pretty metavar representation of a type. Adapts logic from `pydantic._repr.display_as_type`."""
         obj = _strip_annotated(obj)
-        if isinstance(obj, FunctionType):
-            return obj.__name__
+        if _is_function(obj):
+            # If function is locally defined use __name__ instead of __qualname__
+            return obj.__name__ if '<locals>' in obj.__qualname__ else obj.__qualname__
         elif obj is ...:
             return '...'
         elif isinstance(obj, Representation):
@@ -1762,13 +1763,13 @@ def _help_format(self, field_name: str, field_info: FieldInfo, model_default: An
             default = f'(default: {self.cli_parse_none_str})'
             if is_model_class(type(model_default)) or is_pydantic_dataclass(type(model_default)):
                 default = f'(default: {getattr(model_default, field_name)})'
-            elif model_default not in (PydanticUndefined, None) and callable(model_default):
+            elif model_default not in (PydanticUndefined, None) and _is_function(model_default):
                 default = f'(default factory: {self._metavar_format(model_default)})'
             elif field_info.default not in (PydanticUndefined, None):
                 enum_name = _annotation_enum_val_to_name(field_info.annotation, field_info.default)
                 default = f'(default: {field_info.default if enum_name is None else enum_name})'
             elif field_info.default_factory is not None:
-                default = f'(default: {field_info.default_factory})'
+                default = f'(default factory: {self._metavar_format(field_info.default_factory)})'
             _help += f' {default}' if _help else default
         return _help.replace('%', '%%') if issubclass(type(self._root_parser), ArgumentParser) else _help
 
@@ -2092,3 +2093,7 @@ def _annotation_enum_name_to_val(annotation: type[Any] | None, name: Any) -> Any
             if name in tuple(val.name for val in type_):
                 return type_[name]
     return None
+
+
+def _is_function(obj: Any) -> bool:
+    return inspect.isfunction(obj) or inspect.isbuiltin(obj) or inspect.isroutine(obj) or inspect.ismethod(obj)

tests/test_settings.py

@@ -5,6 +5,7 @@
 import pathlib
 import re
 import sys
+import time
 import typing
 import uuid
 from datetime import datetime, timezone
@@ -2553,9 +2554,7 @@ class Cfg(BaseSettings):
   -h, --help  show this help message and exit
   --foo str   (required)
   --bar int   (default: 123)
-  --boo int   (default: <function
-              test_cli_help_differentiation.<locals>.Cfg.<lambda> at
-              0xffffffff>)
+  --boo int   (default factory: <lambda>)
 """
         )
 
@@ -3757,6 +3756,9 @@ class CfgWithSubCommand(BaseSettings):
         (Annotated[SimpleSettings, 'annotation'], 'JSON'),
         (DirectoryPath, 'Path'),
         (FruitsEnum, '{pear,kiwi,lime}'),
+        (time.time_ns, 'time_ns'),
+        (foobar, 'foobar'),
+        (CliDummyParser.add_argument, 'CliDummyParser.add_argument'),
     ],
 )
 @pytest.mark.parametrize('hide_none_type', [True, False])