add shellcheck to flake instead

.github/workflows/test.yml

@@ -1,18 +0,0 @@
-name: test
-on:
-  workflow_dispatch:
-  pull_request:
-    types: [opened, reopened, synchronize]
-
-jobs:
-  lint:
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v3.2.0
-      - name: Install Nix
-        uses: cachix/install-nix-action@v18
-        with:
-          extra_nix_config: access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
-      - name: ShellCheck
-        run: nix-shell --packages git shellcheck --pure --run 'shellcheck disk-deactivate/disk-deactivate disko'

flake.nix

@@ -25,14 +25,20 @@
       default = self.packages.${system}.disko;
     });
     # TODO: disable bios-related tests on aarch64...
+    # Run checks: nix flake check -L
     checks = forAllSystems (system: let
       pkgs = nixpkgs.legacyPackages.${system};
-    in
+      nixosTests = import ./tests {
-      # Run tests: nix flake check -L
-      import ./tests {
         inherit pkgs;
         makeTest = import (pkgs.path + "/nixos/tests/make-test-python.nix");
         eval-config = import (pkgs.path + "/nixos/lib/eval-config.nix");
-      });
+      };
+      shellcheck = pkgs.runCommand "shellcheck" { nativeBuildInputs =  [ pkgs.shellcheck ]; } ''
+        cd ${./.}
+        shellcheck disk-deactivate/disk-deactivate disko
+        touch $out
+      '';
+    in
+      nixosTests // { inherit shellcheck; });
   };
 }