From fad306c58965fd33358c48f2b9d4931bd306cfb4 Mon Sep 17 00:00:00 2001
From: Archit Gupta <archit@accelbread.com>
Date: Wed, 18 Oct 2023 19:58:23 -0700
Subject: [PATCH] Fix merge function for custom option types

If merge is not set for an option type, it will use the default merge
function; this was not what was intended. Updated the merge values for
options that did not set one to mergeOneOption or mergeEqualOption.
---
 builtinModules/templates.nix | 2 ++
 default.nix                  | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/builtinModules/templates.nix b/builtinModules/templates.nix
index 4deaf4b..c02a75b 100644
--- a/builtinModules/templates.nix
+++ b/builtinModules/templates.nix
@@ -7,6 +7,7 @@ let
   inherit (builtins) isPath isString;
   inherit (lib) mkOption mkOptionType mkIf mkMerge;
   inherit (lib.types) lazyAttrsOf nullOr;
+  inherit (lib.options) mergeEqualOption;
 
   template = mkOptionType {
     name = "template";
@@ -15,6 +16,7 @@ let
     check = x: (x ? path) && (isPath x.path) &&
       (x ? description) && (isString x.description) &&
       ((! x ? welcomeText) || (isString x.welcomeText));
+    merge = mergeEqualOption;
   };
 in
 {
diff --git a/default.nix b/default.nix
index 778ab1f..ba4ee8a 100644
--- a/default.nix
+++ b/default.nix
@@ -10,6 +10,7 @@ let
     mapAttrsToList pathExists pipe removePrefix removeSuffix evalModules
     mkDefault mkOptionType singleton;
   inherit (nixpkgs.lib.types) coercedTo functionTo listOf;
+  inherit (nixpkgs.lib.options) mergeEqualOption mergeOneOption;
 
   builtinModules = mapAttrsToList (k: _: ./builtinModules + ("/" + k))
     (readDir ./builtinModules);
@@ -49,6 +50,7 @@ let
         description = "package definition";
         descriptionClass = "noun";
         check = isFunction;
+        merge = mergeOneOption;
       };
 
       path = mkOptionType {
@@ -56,6 +58,7 @@ let
         description = "path";
         descriptionClass = "noun";
         check = isPath;
+        merge = mergeEqualOption;
       };
 
       module = mkOptionType {