rustfmt: fix on darwin

[PuercoPop]

Description of changes

Without this patch rustfmt installs successfully but upon running it it throws the following error

  $ rustfmt
  dyld[68147]: Library not loaded: @rpath/librustc_driver-c577224f5690b349.dylib
    Referenced from: <no uuid> /nix/store/w46inc6cad6xg2kw09v9n629iqb7aqrw-rustfmt-1.69.0/bin/rustfmt
    Reason: tried: '/nix/store/ih18sy1kcbl5kdgq2l8l1lm70ai6aybj-apple-framework-CoreFoundation-11.0.0/Library/Frameworks/librustc_driver-c577224f5690b349.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/nix/store/ih18sy1kcbl5kdgq2l8l1lm70ai6aybj-apple-framework-CoreFoundation-11.0.0/Library/Frameworks/librustc_driver-c577224f5690b349.dylib' (no such file), '/nix/store/ih18sy1kcbl5kdgq2l8l1lm70ai6aybj-apple-framework-CoreFoundation-11.0.0/Library/Frameworks/librustc_driver-c577224f5690b349.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/nix/store/ih18sy1kcbl5kdgq2l8l1lm70ai6aybj-apple-framework-CoreFoundation-11.0.0/Library/Frameworks/librustc_driver-c577224f5690b349.dylib' (no such file), '/usr/local/lib/librustc_driver-c577224f5690b349.dylib' (no such file), '/usr/lib/librustc_driver-c577224f5690b349.dylib' (no such file, not in dyld cache)
  Abort trap: 6

Reading this rust-issue it seems that we have to link against rustc_driver. The clippy.nix expression already does something similar

Of the 4 executables found in the result of building rustfmt only rustfmt and git-rustfmt needed to be linked. The other worked without linking to rustc_driver.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 23.05 Release Notes (or backporting 22.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

[PuercoPop]

The editorconfig check is failing, I can't find the error message in the web UI. I tried reproducing the failure locally but it doesn't seem to complain:

cd ~/src/nixpkgs
$ nix-shell -p editorconfig-checker

[nix-shell:~/src/nixpkgs]$ editorconfig-checker -disable-indent-size pkgs/development/compilers/rust/rustfmt.nix 

[nix-shell:~/src/nixpkgs]$ echo $?
0

[winterqt]

Blame GitHub -- I re-ran it, and it passed.

[winterqt]

Might be worth adding my comment from Clippy's derivation here, or just reference it.

[PuercoPop]

I agree that it should be commented. I was unsure on what was the best way to do so. I've copied the comment verbatim.

[winterqt]

Commit message needs to be in proper form, e.g. rustfmt: fix on darwin.

[winterqt]

I'd also argue that the commit message can be shortened significantly, as we already explain why this workaround is needed in the Clippy derivation/commits, but maybe I'm nitpicking too much :)

[PuercoPop]

Thanks for the swift review. I've updated the commit header line as requested and removed some of the specific details of the commit message. Let me know what you think

[winterqt]

Just changed the commit message to remove the extraneous Darwin mention.

[winterqt]

Tested, thanks!

[winterqt]

Skipping OfBorg because I've already tested this extensively, and it seems to be very backed up right now.