`Component` derive macro does not work with `#![feature(default_field_values)]` structs

[yackimoff]

Bevy version

0.16

What you did

I've turned on #![feature(default_field_values)] for the crate and wanted to specify default values for my component struct. Like:

#[derive(Component, Default)]
pub struct ConveyorBelt {
    pub speed: f32 = 1.0, // I get "expected ','" message here
}

What went wrong

It appears that #[derive(Component)] does not work for structs which have default values in their declared fields.

Additional information

The main problem is that the diagnostics is very vague. I couldn't figure out that the issue is in Component derive implementation.

[notmd]

Havent tested yet but I think the problem is syn doesn't parse default_field_values dtolnay/syn#1774

[yackimoff]

Oh, so it's not in bevy's code? Then, I guess, the issue could be closed?

[gmorenz]

For what it's worth I just discovered that Event also doesn't, when I just tried turning this on.

[mockersf]

Oh, so it's not in bevy's code? Then, I guess, the issue could be closed?

We can keep it open to help people who would try searching for the same issue, but nothing we can do on Bevy side