Tyro marks attrs fields with default values as "fixed"

[shermansiu]

Unlike for dataclasses, tyro marks fields with default values as being "fixed to" the default value.

The tyro version is 0.7.2 and the attrs version is 23.2.0, on Python 3.10.

[shermansiu]

It does not matter if the dataclass/attrs class is frozen or not, the bug persists in either case.

[brentyi]

Thanks for reporting this @shermansiu!

Are you able to share a runnable example?

That sounds unideal. I spotted some attrs-related issues when I was trying to reproduce this (fixed in #126), but couldn't figure out the specific behavior you're describing.

This works as expected for me:

from __future__ import annotations

from attrs import define, field

import tyro

@define
class Args:
    x: int = field(default=2)
    y: tuple[int, ...] = field(default=(1, 2, 3))
    z: int = field(default=5)

if __name__ == "__main__":
    args = tyro.cli(Args)
    print(args)

[shermansiu]

Thanks, I think #126 fixes this issue.

With the sample script you provided, I get the following error for the dev version before #126:

$ python test.py --help
usage: test.py [-h] [--x {fixed}] [--y {fixed}] [--z {fixed}]

Method generated by attrs for class Args.

╭─ options ──────────────────────────────────────────╮
│ -h, --help         show this help message and exit │
│ --x {fixed}        (fixed to: 2)                   │
│ --y {fixed}        (fixed to: 1 2 3)               │
│ --z {fixed}        (fixed to: 5)                   │
╰────────────────────────────────────────────────────╯
$ python test.py
Args(x=2, y=(1, 2, 3), z=5)
$ python test.py --x 3
╭─ Value error ────────────────────────────────────────────────────────────────╮
│ Error parsing --x: --x was passed in, but is a fixed argument that cannot be │
│ parsed                                                                       │
│ ──────────────────────────────────────────────────────────────────────────── │
│ Argument helptext:                                                           │
│     --x {fixed}                                                              │
│     (fixed to: 2)                                                            │
│ ──────────────────────────────────────────────────────────────────────────── │
│ For full helptext, see test.py --help

After the commit, everything works as expected.

[brentyi]

Oops, for posterity I meant to write:

from attrs import define, field

import tyro

@define
class Args:
    x: int = field(default=2)
    y: tuple[int, ...] = field(default=(1, 2, 3))
    z: int = field(default=5)

if __name__ == "__main__":
    args = tyro.cli(Args)
    print(args)

which was working without the __future__ import.

Glad things are fixed for you!

[shermansiu]

Thanks! Looking forward to the next release, when I can use the version from PyPi and not a custom installation!

[brentyi]

Should be available already 🙂