Avoid --impure in flake-parts based projects

cachix · Mar 20, 2024 · 5efce28 · 5efce28
1 parent cbd16d2
commit 5efce28
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Showing 2 changed files with 13 additions and 2 deletions.
diff --git a/templates/flake-parts/.envrc b/templates/flake-parts/.envrc
@@ -5,7 +5,8 @@ fi
 nix_direnv_watch_file devenv.nix
 nix_direnv_watch_file devenv.lock
 nix_direnv_watch_file devenv.yaml
-if ! use flake . --impure
+
+if ! use flake . --override-input devenv-root "file+file:"<(printf %s "$PWD")
 then
   echo "devenv could not be built. The devenv environment was not loaded. Make the necessary changes to devenv.nix and hit enter to try again." >&2
 fi
diff --git a/templates/flake-parts/flake.nix b/templates/flake-parts/flake.nix
@@ -2,6 +2,10 @@
   description = "Description for the project";
 
   inputs = {
+    devenv-root = {
+      url = "file+file:/dev/null";
+      flake = false;
+    };
     nixpkgs.url = "github:cachix/devenv-nixpkgs/rolling";
     devenv.url = "github:cachix/devenv";
     nix2container.url = "github:nlewo/nix2container";
@@ -14,7 +18,7 @@
     extra-substituters = "https://devenv.cachix.org";
   };
 
-  outputs = inputs@{ flake-parts, ... }:
+  outputs = inputs@{ flake-parts, devenv-root, ... }:
     flake-parts.lib.mkFlake { inherit inputs; } {
       imports = [
         inputs.devenv.flakeModule
@@ -33,6 +37,12 @@
         packages.default = pkgs.hello;
 
         devenv.shells.default = {
+          devenv.root =
+            let
+              devenvRootFileContent = builtins.readFile devenv-root.outPath;
+            in
+            nixpkgs.lib.mkIf (devenvRootFileContent != "") devenvRootFileContent;
+
           name = "my-project";
 
           imports = [