example in README.md doesn't work with rust-toolchain.toml file

[woss]

Following the example that is given in the README.md

# shell.nix
let
  moz_overlay = import (builtins.fetchTarball https://github.com/mozilla/nixpkgs-mozilla/archive/master.tar.gz);
  nixpkgs = import <nixpkgs> { overlays = [ moz_overlay ]; };
in
  with nixpkgs;
  stdenv.mkDerivation {
    name = "moz_overlay_shell";
    buildInputs = [
      # to use the latest nightly:
      #nixpkgs.latest.rustChannels.nightly.rust
      # to use a specific nighly:
      # (nixpkgs.rustChannelOf { date = "2018-04-11"; channel = "nightly"; }).rust
      # to use the project's rust-toolchain file:
      (nixpkgs.rustChannelOf { rustToolchain = ./rust-toolchain.toml; }).rust
    ];
  }

and my rust-toolchain.toml

[toolchain]
channel = "nightly-2022-02-23"
components = ["rustfmt", "rustc-dev", "rust-std", "rust-analysis", "rust-src"]
targets = ["wasm32-unknown-unknown", "x86_64-unknown-linux-gnu"]
profile = "default"

fails when I change the rust-toolchain to rust-toolchain.toml with the following error:

❯ nix-shell --pure  shell.nix
error: unable to download 'https://static.rust-lang.org/dist/channel-rust-nightly-2022-02-23.toml': HTTP error 404 ('')
(use '--show-trace' to show detailed location information)

Then I run it with the show-trace

❯ nix-shell --pure --show-trace shell.nix
error: unable to download 'https://static.rust-lang.org/dist/channel-rust-nightly-2022-02-23.toml': HTTP error 404 ('')

       … while evaluating 'flip'

       at /nix/store/b6n2pql0s2fval4hy7mczy1l9rq9v3yd-nixpkgs-21.11pre326916.7053541084b/nixpkgs/lib/trivial.nix:138:16:

          137|   */
          138|   flip = f: a: b: f b a;
             |                ^
          139|

       … from call site

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:269:5:

          268|     in
          269|     flip mapAttrs pkgs.pkg (name: pkg:
             |     ^
          270|       makeOverridable ({extensions, targets, targetExtensions}:

       … while evaluating 'fromManifestFile'

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:262:32:

          261|   #                       you will need to specify this extension in the extensions options or it will not be installed!
          262|   fromManifestFile = manifest: { stdenv, lib, fetchurl, patchelf }:
             |                                ^
          263|     let

       … from call site

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:318:8:

          317|     let manifestFile = if sha256 == null then builtins.fetchurl manifest else fetchurl { url = manifest; inherit sha256; };
          318|     in fromManifestFile manifestFile { inherit stdenv lib fetchurl patchelf; };
             |        ^
          319|

       … while evaluating 'fromManifest'

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:316:36:

          315|
          316|   fromManifest = sha256: manifest: { stdenv, lib, fetchurl, patchelf }:
             |                                    ^
          317|     let manifestFile = if sha256 == null then builtins.fetchurl manifest else fetchurl { url = manifest; inherit sha256; };

       … from call site

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:330:59:

          329|
          330|   rustChannelOf = { sha256 ? null, ... } @ manifest_args: fromManifest
             |                                                           ^
          331|     sha256 (manifest_v2_url manifest_args)

       … while evaluating 'rustChannelOf'

       at /nix/store/5snmi8nb601c90swp17b96g3a1622366-source/rust-overlay.nix:330:19:

          329|
          330|   rustChannelOf = { sha256 ? null, ... } @ manifest_args: fromManifest
             |                   ^
          331|     sha256 (manifest_v2_url manifest_args)

       … from call site

       at /home/daniel/projects/work/anagolay/operations/op-cid/shell.nix:14:8:

           13|       # to use the project's rust-toolchain file:
           14|       (nixpkgs.rustChannelOf { rustToolchain = ./rust-toolchain.toml; }).rust
             |        ^
           15|     ];

       … while evaluating anonymous lambda

       at /nix/store/b6n2pql0s2fval4hy7mczy1l9rq9v3yd-nixpkgs-21.11pre326916.7053541084b/nixpkgs/pkgs/stdenv/generic/make-derivation.nix:156:13:

          155|       (map (drv: drv.__spliced.hostHost or drv) depsHostHost)
          156|       (map (drv: drv.crossDrv or drv) buildInputs)
             |             ^
          157|     ]

       … from call site

       … while evaluating 'getOutput'

       at /nix/store/b6n2pql0s2fval4hy7mczy1l9rq9v3yd-nixpkgs-21.11pre326916.7053541084b/nixpkgs/lib/attrsets.nix:489:23:

          488|   */
          489|   getOutput = output: pkg:
             |                       ^
          490|     if ! pkg ? outputSpecified || ! pkg.outputSpecified

       … from call site

       … while evaluating the attribute 'buildInputs' of the derivation 'moz_overlay_shell'

       at /nix/store/b6n2pql0s2fval4hy7mczy1l9rq9v3yd-nixpkgs-21.11pre326916.7053541084b/nixpkgs/pkgs/stdenv/generic/make-derivation.nix:205:7:

          204|     // (lib.optionalAttrs (attrs ? name || (attrs ? pname && attrs ? version)) {
          205|       name =
             |       ^
          206|         let

I am not well versed in the nix lang so I cannot even debug this. i found this #281 and thought it should work without any issues, but it seems it doesn't for me.

Is there something I am doing wrong or this is a bug? thx

[magistau]

I happen to get the same problem unfortunately