Implementing default with default - recursion

[mikatpt]

Description

Hey, this is probably a pretty silly feature request, but this tripped me up way more than it should have.

Normally, if you try to implement Default and use ..Default::default(), it'll give you the following warning:
recursive call site [unconditional_recursion].

However, if you add any function call, this will no longer happen.

pub struct Test {
    pub a: String,
    pub b: i32,
}

impl Default for Test {
    fn default() -> Self {
        let test = "test".to_string();
        Self {
            a: test,
            ..Default::default() // No compiler warning!
        }
    }
}

In retrospect, this is exceptionally obvious. But my intuitive thought when I was writing that line was that the remaining fields would be implemented with Default, not that it would refer to the struct itself. Rust Analyzer even suggests using it... not that that's any excuse either, but I lost a lot of time to this particular footgun 😞

Related issue: #103

Version

No response

Additional Labels

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[kraktus]

Running the snippet on playground, the compiler fires a warning. Note that this is rustc warning, not a clippy one.

[thehappycheese]

Just blew my toes off with the same "stack overflow";

@kraktus I don't see any warning in the terminal... perhaps it would appear if I recompiled from scratch?

use bevy::{prelude::*, audio::{PlaybackMode, Volume}};
use bevy_turborand::prelude::*;

#[derive(Component)]
pub struct FootStepSounds {
    pub last_position     : Vec3,
    pub movement_distance : f32,
    pub stride_length     : f32,
    pub elapsed_time      : f32,
    pub stride_time       : f32,
    pub sound_assets      : Vec<Handle<AudioSource>>,
}

impl Default for FootStepSounds {
    fn default() -> Self {
        Self {
            stride_length     : 20.0,
            stride_time       : 0.3,
            // elapsed_time      : 0.0,
            // movement_distance : 0.0,
            // last_position     : Vec3::ZERO,
            // sound_assets      : vec![],
            ..default() // <-- stack overflow
        }
    }
}

Like @mikatpt I also think it seems like a perfectly reasonable thing to try, but obvious why it cant work. Hopefully there is like a ..super_default() or a ..partial_default() in the future :)