refactor: use pkgs.writeShellApplication (#2)

.github/workflows/check.yaml

@@ -1,18 +1,14 @@
-name: Build example and run tests
+name: Build and test example flake
 
 on:
  pull_request:
- push:
- branches:
- - main
 
 jobs:
- tests:
+ check-pr:
  runs-on: ubuntu-latest
  steps:
  - uses: actions/checkout@v4
  - uses: cachix/install-nix-action@v25
  with:
  github_access_token: ${{ secrets.GITHUB_TOKEN }}
- - run: nix build ./example
- - run: nix run ./example#test
+ - run: nix run .#check-local

.github/workflows/update-example.yaml

@@ -1,4 +1,4 @@
-name: Update example flake
+name: Update, build and test example flake
 
 on:
  push:
@@ -17,6 +17,7 @@ jobs:
  with:
  github_access_token: ${{ secrets.GITHUB_TOKEN }}
  - run: nix flake lock --update-input neovim-nix ./example
+ - run: nix run .#check
  - run: |
  git config --global user.name 'github-actions[bot]'
  git config --global user.email '[email protected]'

flake.nix

@@ -33,6 +33,21 @@
  system,
  ...
  }: {
+ apps = {
+ check.program = pkgs.writeShellApplication {
+ name = "check";
+ text = ''
+ nix run ./example#test
+ '';
+ };
+ check-local.program = pkgs.writeShellApplication {
+ name = "check-local";
+ text = ''
+ nix run --override-input neovim-nix path:./. ./example#test
+ '';
+ };
+ };
+
  devShells.default = pkgs.mkShell {
  name = "neovim.nix";
  shellHook = ''

modules/default.nix

@@ -4,58 +4,37 @@
  ...
 }: let
  inherit (flake-parts-lib) mkPerSystemOption;
- inherit (lib) concatStringsSep makeBinPath mapAttrsToList mkOption optional types unique;
+ inherit (lib) concatStringsSep makeBinPath mapAttrsToList mkOption optional optionals types unique;
 
  mkNeovimEnv = {
  config,
  pkgs,
  ...
  }: let
  cfg = config.neovim;
-
-  # TODO: Use wrapProgram?
- wrapper = pkgs.writeTextFile rec {
+ toEnvVar = name: value: ''export ${name}="''${${name}:-${toString value}}"'';
+ in
+ pkgs.writeShellApplication {
  name = "nvim";
- executable = true;
- destination = "/bin/${name}";
- text = concatStringsSep "\n" ([
- ''
- #!${pkgs.runtimeShell}
- set -o errexit
- set -o nounset
- set -o pipefail
- ''
- ]
+ text = concatStringsSep "\n" (
+ # NOTE: We don't use writeShellApplication's `runtimeEnv` argument since
+ # it does not allow the specified environment variables to be overridden
+ # (e.g. by direnv).
+ optionals (cfg.env != {}) (mapAttrsToList toEnvVar cfg.env)
+ # NOTE: Similar sentiment here. We don't use writeShellApplication's
+ # `runtimeInputs` because it would *prepend* `cfg.paths`. What we want,
+ # rather, is to *append* them such that they too can be overridden.
  ++ optional (cfg.paths != []) ''
  export PATH="$PATH:${makeBinPath (unique cfg.paths)}"
  ''
- ++ [
- ''
- ${concatStringsSep "\n" (mapAttrsToList (name: value: ''export ${name}="''${${name}:-${toString value}}"'') cfg.env)}
- ''
- ]
  ++ [
  ''
  export NVIM_RPLUGIN_MANIFEST="${config.neovim.build.rplugin}/rplugin.vim"
  ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
  ''
- ]);
-
- checkPhase = ''
- runHook preCheck
- ${pkgs.stdenv.shellDryRun} "$target"
- ${pkgs.shellcheck}/bin/shellcheck "$target"
- runHook postCheck
- '';
-
- meta.mainProgram = name;
- };
- in
- pkgs.buildEnv {
- name = "neovim-env";
- paths = [wrapper];
- meta.mainProgram = "nvim";
- passthru = {
+ ]
+ );
+ derivationArgs.passthru = {
  inherit (config.neovim.build) initlua plugins;
  };
  };