From a3a96a74af5be83e500dce154a3556486c039ac3 Mon Sep 17 00:00:00 2001
From: Thiago Kenji Okada <thiagokokada@gmail.com>
Date: Thu, 5 Oct 2023 22:47:25 +0100
Subject: [PATCH] flake.nix: add devShell

That is basically my Home-Manager configuration.
---
 flake.nix                      | 48 +++++++++++++++++++++++++++++++++-
 home-manager/editor/neovim.nix |  2 +-
 2 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/flake.nix b/flake.nix
index fe4fa51f..1053f9ac 100644
--- a/flake.nix
+++ b/flake.nix
@@ -112,7 +112,7 @@
     };
   };
 
-  outputs = { self, nixpkgs, ... }@inputs:
+  outputs = { self, nixpkgs, flake-utils, ... }@inputs:
     let
       inherit (import ./lib/attrsets.nix { inherit (nixpkgs) lib; }) recursiveMergeAttrs;
       inherit (import ./lib/flake.nix inputs) mkGHActionsYAMLs mkRunCmd mkNixOSConfig mkHomeConfig;
@@ -190,5 +190,51 @@
         "update-flakes-darwin"
         "validate-flakes"
       ])
+
+      (flake-utils.lib.eachDefaultSystem (system:
+        let
+          pkgs = nixpkgs.legacyPackages.${system};
+          homeManager = (mkHomeConfig {
+            inherit system;
+            hostname = "devShell";
+            homePath = "/tmp";
+            username = "home";
+            extraModules = [{
+              # Disable systemd services/sockets/timers/etc.
+              systemd.user = {
+                automounts = pkgs.lib.mkForce { };
+                mounts = pkgs.lib.mkForce { };
+                paths = pkgs.lib.mkForce { };
+                services = pkgs.lib.mkForce { };
+                sessionVariables = pkgs.lib.mkForce { };
+                slices = pkgs.lib.mkForce { };
+                sockets = pkgs.lib.mkForce { };
+                targets = pkgs.lib.mkForce { };
+                timers = pkgs.lib.mkForce { };
+              };
+            }];
+          }).homeConfigurations.devShell;
+        in
+        {
+          devShells.default = pkgs.mkShell {
+            shellHook = ''
+              # Home Manager checks if the USER environment variable matches
+              # username
+              OLD_USER="$USER"
+              export USER="${homeManager.config.home.username}"
+              export HOME="${homeManager.config.home.homeDirectory}"
+              mkdir -p $HOME
+
+              trap "rm -rf $HOME" EXIT
+
+              ${homeManager.activationPackage}/activate
+
+              export USER="$OLD_USER"
+              unset OLD_USER
+
+              zsh -l && exit 0
+            '';
+          };
+        }))
     ]); # END recursiveMergeAttrs
 }
diff --git a/home-manager/editor/neovim.nix b/home-manager/editor/neovim.nix
index a6320e67..22acd215 100644
--- a/home-manager/editor/neovim.nix
+++ b/home-manager/editor/neovim.nix
@@ -164,7 +164,7 @@ in
               ignore = {},
               devicons = {
                 enable = ${if cfg.enableIcons then "true" else "false"},
-                highlight_dirname = false
+                highlight_dirname = false,
               },
               mappings = {
                 ['<Enter>'] = actions.edit,