Remove check-fmt script

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
     - uses: cachix/install-nix-action@v12
     - uses: actions/checkout@v1
     - name: Check format
-      run: ./check-fmt
+      run: nix-shell --run 'nixpkgs-fmt --check .'
 
   build:
     runs-on: ${{ matrix.os }}

check-fmt

@@ -1,10 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell ./shell.nix -i bash
-#
-# Just because the nixpkgs-fmt error message is not super readable. Used by
-# CI.
-
-if ! nixpkgs-fmt --check . ; then
-  echo 'run `nixpkgs-fmt .` to fix it'
-  exit 1
-fi