[fix] flake.nix: use runCommandNoCC for checks

It's much simpler and allows us to embed it into the flake.nix

flake.nix

@@ -101,14 +101,20 @@
           path = ./.;
           name = "configuration.nix";
         };
+        runCmdInSrc = name: cmd:
+          pkgs.runCommandNoCC name {} ''
+            cd ${src}
+            ${cmd}
+            mkdir $out
+          '';
       in {
         nvim = nixvim.lib.${system}.check.mkTestDerivationFromNixvimModule {
           pkgs = import nixpkgs {inherit system overlays;};
           module = ./nvim/standalone.nix;
         };
-        fmt = pkgs.callPackage ./fmt.nix {inherit src;};
-        lint = pkgs.callPackage ./lint.nix {inherit src;};
-        typos = pkgs.callPackage ./lint.nix {inherit src;};
+        fmt = runCmdInSrc "fmt-src" "${lib.getExe self.formatter.${system}} --check .";
+        lint = runCmdInSrc "lint-src" "${lib.getExe pkgs.statix} check .";
+        typos = runCmdInSrc "typos-src" "${lib.getExe pkgs.typos} .";
       }
     );
 

fmt.nix

@@ -1,12 +0,0 @@
-{
-  lib,
-  stdenvNoCC,
-  alejandra,
-  src,
-}:
-stdenvNoCC.mkDerivation {
-  name = "fmt-src";
-  inherit src;
-  buildPhase = "${lib.getExe alejandra} --check .";
-  installPhase = "mkdir $out";
-}

lint.nix

@@ -1,12 +0,0 @@
-{
-  lib,
-  stdenvNoCC,
-  statix,
-  src,
-}:
-stdenvNoCC.mkDerivation {
-  name = "lint-src";
-  inherit src;
-  buildPhase = "${lib.getExe statix} check .";
-  installPhase = "mkdir $out";
-}

typos.nix

@@ -1,12 +0,0 @@
-{
-  lib,
-  stdenvNoCC,
-  typos,
-  src,
-}:
-stdenvNoCC.mkDerivation {
-  name = "typos-src";
-  inherit src;
-  buildPhase = "${lib.getExe typos} .";
-  installPhase = "mkdir $out";
-}