modules/direnv: Implement pre-cached devshells

That means, that the devshells are only build once and centrally
updated. Ideally, they would be built upon system update, but I haven't
figured out a way to run `nix print-dev-env` in a nix build sandbox yet
(and hope, that it's not necessary anymore once, that functionality
moves to nixpkgs' `mkShell`).

1 files changed, 29 insertions, 10 deletions

diff --git a/modules/by-name/di/direnv/module.nix b/modules/by-name/di/direnv/module.nix
index 363f5cea..743375af 100644
--- a/modules/by-name/di/direnv/module.nix
+++ b/modules/by-name/di/direnv/module.nix
@@ -11,26 +11,45 @@
   config,
   lib,
   pkgs,
+  sources,
   ...
 }: let
   cfg = config.soispha.programs.direnv;
+
+  devshells = sources.loadFlake "devshells";
+
+  pre-cache = pkgs.runCommand "pre-cache.sh" {} ''
+    cat "${./pre-cache.sh}" > $out
+
+    substituteInPlace $out \
+      --replace-fail "%DEVSHELLS_REPO%" "${devshells}"
+  '';
 in {
   options.soispha.programs.direnv = {
     enable = lib.mkEnableOption "direnv";
   };
 
-  config.home-manager.users.soispha.programs.direnv = lib.mkIf cfg.enable {
-    enable = true;
-
-    nix-direnv = {
+  config.home-manager.users.soispha = lib.mkIf cfg.enable {
+    programs.direnv = {
       enable = true;
-      package = pkgs.nix-direnv.override {nix = config.nix.package;};
-    };
 
-    config = {
-      warn_timeout = 0;
-      # strict_env = true;
-      # disable_stdin = true;
+      package = pkgs.direnv-patched;
+
+      nix-direnv = {
+        enable = true;
+        package = pkgs.nix-direnv.override {nix = config.nix.package;};
+      };
+
+      config = {
+        warn_timeout = 0;
+        strict_env = true;
+        # disable_stdin = true;
+      };
+    };
+    xdg.configFile = {
+      "direnv/lib/hm-pre-cache.sh" = {
+        source = pre-cache;
+      };
     };
   };
 }