From 9aca28b01253da5b182d5b75ed269da3de87c813 Mon Sep 17 00:00:00 2001
From: Thomas Schwanberger <thomas@schwanberger.dk>
Date: Sun, 2 Jun 2024 00:34:36 +0200
Subject: [PATCH] Support specifying extra emacs pkgs from nixpkgs

---
 checks.nix       |  4 ++++
 default.nix      |  6 ++++--
 home-manager.nix | 18 ++++++++++++++++--
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/checks.nix b/checks.nix
index 36f32c2..92e8b44 100644
--- a/checks.nix
+++ b/checks.nix
@@ -67,6 +67,10 @@ in {
   minimalEmacs = (makeDoomPackages (common // {
     doomDir = minimalDoomDir;
   })).emacsWithDoom;
+  minimalExtraPackages = mkDoom {
+    doomDir = minimalDoomDir;
+    extraPackages = epkgs: [ epkgs.vterm epkgs.treesit-grammars.with-all-grammars ];
+  };
   allModules = mkDoom { doomDir = allModsDoomDir; };
   allModulesAndFlags = mkDoom { doomDir = allFlagsDoomDir; };
   example = mkDoom { doomDir = ./doomdir; };
diff --git a/default.nix b/default.nix
index e460f7e..1cf3471 100644
--- a/default.nix
+++ b/default.nix
@@ -38,6 +38,8 @@
   noProfileHack ? false,
   /* Use fetchTree instead of fetchGit for package fetches. */
   experimentalFetchTree ? false,
+  /* Extra emacs packages from nixpkgs */
+  extraPackages ? epkgs: [ ],
 
   callPackages,
   git,
@@ -330,8 +332,8 @@ let
 
   # Step 3: Build an emacsWithPackages, pulling all packages from step 1 from
   # the set from step 2.
-  emacsWithPackages = doomEmacsPackages.emacsWithPackages
-    (epkgs: (map (p: epkgs.${p}) (builtins.attrNames doomPackageSet)));
+    emacsWithPackages = doomEmacsPackages.emacsWithPackages
+      (epkgs: (map (p: epkgs.${p}) (builtins.attrNames doomPackageSet)) ++ (extraPackages epkgs));
 
   # Step 4: build a DOOMDIR, Doom profile and profile loader using Emacs from
   # step 3 and packages.el from step 1.
diff --git a/home-manager.nix b/home-manager.nix
index a438366..96d3ace 100644
--- a/home-manager.nix
+++ b/home-manager.nix
@@ -17,7 +17,7 @@
 
 let
   cfg = config.programs.doom-emacs;
-  inherit (lib) literalExpression mkEnableOption mkIf mkMerge mkOption types;
+  inherit (lib) literalExpression mkEnableOption mkIf mkMerge mkOption types hm;
 in {
   options = {
     programs.doom-emacs = {
@@ -94,13 +94,27 @@ in {
         readOnly = true;
         description = "The final doom-emacs package";
       };
+
+      extraPackages = mkOption {
+        default = self: [ ];
+        type = hm.types.selectorFunction;
+        defaultText = "epkgs: [ ]";
+        example = literalExpression
+          "epkgs: [ epkgs.vterm epkgs.treesit-grammars.with-all-grammars ]";
+        description = ''
+          Extra packages available to Doom Emacs.
+          To let nix handle a doom dependency '(package! ...)' we can leverage the ':built-in t' argument
+          Consider the following example for 'vterm' in the doom config packages.el:
+          (package! vterm :built-in t)
+        '';
+      };
     };
   };
 
   config = mkIf cfg.enable (mkMerge [
     (let
       doomPackages = doomFromPackages pkgs {
-        inherit (cfg) emacs doomDir doomLocalDir profileName noProfileHack;
+        inherit (cfg) emacs doomDir doomLocalDir profileName noProfileHack extraPackages;
       };
     in
       {