nix/templates/pkg/rust doesn't build

[greg-freewave]

Because colored is locked to an incompatible version:

$> nix build
warning: Ignoring setting 'auto-allocate-uids' because experimental feature 'auto-allocate-uids' is not enabled
warning: Ignoring setting 'impure-env' because experimental feature 'configurable-impure-env' is not enabled
error: builder for '/nix/store/8sk7svbrswlxj7yys5fcdg95vs16fzd3-zero-to-nix-rust.drv' failed with exit code 101;
       last 10 log lines:
       > Finished cargoSetupPostPatchHook
       > updateAutotoolsGnuConfigScriptsPhase
       > configuring
       > building
       > Executing cargoBuildHook
       > ++ env CC_aarch64-apple-darwin=/nix/store/rkyh698841ab0n8ki2cchfzws63jh4mh-clang-wrapper-11.1.0/bin/cc CXX_aarch64-apple-darwin=/nix/store/rkyh698841ab0n8ki2cchfzws63jh4mh-clang-wrapper-11.1.0/bin/c++ CC_aarch64-apple-darwin=/nix/store/rkyh698841ab0n8ki2cchfzws63jh4mh-clang-wrapper-11.1.0/bin/cc CXX_aarch64-apple-darwin=/nix/store/rkyh698841ab0n8ki2cchfzws63jh4mh-clang-wrapper-11.1.0/bin/c++ cargo build -j 12 --target aarch64-apple-darwin --frozen --release
       > error: package `colored v2.1.0` cannot be built because it requires rustc 1.70 or newer, while the currently active rustc version is 1.69.0
       > Either upgrade to rustc 1.70 or newer, or use
       > cargo update -p colored@2.1.0 --precise ver
       > where `ver` is the latest version of `colored` supporting rustc 1.69.0
       For full logs, run 'nix log /nix/store/8sk7svbrswlxj7yys5fcdg95vs16fzd3-zero-to-nix-rust.drv'.

The solution i worked is to nix develop then cargo update -p colored@2.1.0 --precise 2.0.0 and I'm happy to create a PR with the changed Cargo.lock but I don't know that's the best way to fix this so I figured I'd open the issue and see what folks think.

[lucperkins]

@greg-freewave Good catch! A fix is on the way 😄