Optional[Path] = typer.Argument returns TypeError when passed into open()

[EndlessTrax]

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Example Code

# cli.py
@app.command()
def main(
    config_file: Optional[Path] = typer.Argument(
        "config.yaml",  # Default if not provided
        exists=True,
        file_okay=True,
        dir_okay=False,
        writable=False,
        readable=True,
        resolve_path=True,
    )
):

    config_data = parse_yaml_config_file(config_file)

# config.py
import yaml

def parse_yaml_config_file(file) -> dict:
    with open(file) as yaml_file:
        return yaml.safe_load(yaml_file)

Description

The above code works as expected in dev, and all unit tests pass. However, after creating a wheel and installing into a test venv I get the following Traceback:

Traceback (most recent call last):
  File "C:\Users\RickyWhite\AppData\Local\Programs\Python\Python310\lib\runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "C:\Users\RickyWhite\AppData\Local\Programs\Python\Python310\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "C:\Users\RickyWhite\OneDrive - The Migus Group\Desktop\Test\venv\Scripts\hofund.exe\__main__.py", line 7, in <module>
  File "C:\Users\RickyWhite\OneDrive - The Migus Group\Desktop\Test\venv\lib\site-packages\hofund\cli.py", line 37, in main
    config_data = parse_yaml_config_file(config_file)
  File "C:\Users\RickyWhite\OneDrive - The Migus Group\Desktop\Test\venv\lib\site-packages\hofund\config.py", line 8, in parse_yaml_config_file
    with open(config_file) as yaml_file:
TypeError: expected str, bytes or os.PathLike object, not ArgumentInfo

I've check my debugger and with print, and the config_file is indeed a WindowsPath object.

I've tried converting to a str, but get an OSError: [Errno 22] Invalid argument: '<typer.models.ArgumentInfo object at 0x000001F590930DC0>' error instead.

I'm not sure why it seems to be of type ArgumentInfo when installed from a wheel, but WindowsPath object when ran locally. 😕

Operating System

Windows

Operating System Details

Windows 11
OS build 22000.438

Typer Version

0.4.0

Python Version

3.10

Additional Context

No response

[Mirandatz]

Maybe you are using calling main() instead of typer.run(main)?

[gchhablani]

I am facing a similar issue when using typer.Option(None).
Basically, I am trying to use file:str=typer.Option(None) as default value for a file path input and then trying to read it from somewhere.

However, during the check if file is None, I get a False as output.

A snippet for the explaining the basic issue is there:

>>> import typer
>>> var =  typer.Option(None)
>>> var
<typer.models.OptionInfo object at 0x7fc09002d880>
>>> var is None
False

The expectation is that var is None should return True.

This causes the error that I get:

AttributeError: 'OptionInfo' object has no attribute 'open'

as I am trying to read the file.

[johnthagen]

@Mirandatz nailed it ❤️.

In my case I had a entry point defined with Poetry:

[tool.poetry.scripts]
fact = "fact.cli:main"

But I was pointing that to:

def main(n: int = Argument(..., min=0, help="The input n of fact(n)")) -> None:

But that wasn't being wrapped in typer.run(main).

I fixed this by pointing the console script at:

def entry_point() -> None:
    typer.run(main)