Suggested rust-analyzer config can't run rustfmt

[jyn514]

#107297 broke the rust-analyzer config we suggest in the dev-guide: https://rustc-dev-guide.rust-lang.org/building/suggested.html#configuring-rust-analyzer-for-rustc

    "rust-analyzer.rustfmt.overrideCommand": [
        "./build/host/stage0/bin/rustfmt",
        "--edition=2021"
    ],

since now rustfmt is in build/host/rustfmt/bin/rustfmt instead of build/host/stage0/bin/rustfmt.

Originally posted by @jyn514 in #107297 (comment)

[zephaniahong]

@rustbot claim

[zephaniahong]

Hi! Just to clarify, the idea is to change to code to match the docs?

[albertlarsan68]

I think the idea is changing the docs to match the new behavior.

[zephaniahong]

For reference: rust-lang/rustc-dev-guide#1574

[jyn514]

I'd prefer to change the code so that we don't force all contributors to update their config.

[Mark-Simulacrum]

I don't think we can put the binary back, or at least, that feels iffy - we'd be trying to overlap two different sysroots. rustfmt used to be statically linked to libstd and librustc_driver, but that's no longer the case.

[Mark-Simulacrum]

I suppose we could try to create a symlink from the old path to the new one? That might work, not sure.

[albertlarsan68]

Maybe add a proxy?
On Linux it might just be

#!/usr/bin/sh
exec ../rustdoc $* #FIXME make this syntax correct

[jyn514]

A symlink seems like a good solution to me.

[albertlarsan68]

Does the symlink still finds the correct so?