From 0a6f3e992f4e4cde0b3c7f0e92b92c7c4e0bd749 Mon Sep 17 00:00:00 2001
From: winston <hey@winston.sh>
Date: Tue, 12 Mar 2024 01:39:57 +0100
Subject: [PATCH 1/5] refactor: use `pkgs.writeShellApplication`

---
 modules/default.nix | 56 +++++++++++----------------------------------
 1 file changed, 13 insertions(+), 43 deletions(-)

diff --git a/modules/default.nix b/modules/default.nix
index 0f8bf6d..042121e 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -4,7 +4,7 @@
   ...
 }: let
   inherit (flake-parts-lib) mkPerSystemOption;
-  inherit (lib) concatStringsSep makeBinPath mapAttrsToList mkOption optional types unique;
+  inherit (lib) mkOption types;
 
   mkNeovimEnv = {
     config,
@@ -12,50 +12,20 @@
     ...
   }: let
     cfg = config.neovim;
-
-    # TODO: Use wrapProgram?
-    wrapper = pkgs.writeTextFile rec {
-      name = "nvim";
-      executable = true;
-      destination = "/bin/${name}";
-      text = concatStringsSep "\n" ([
-          ''
-            #!${pkgs.runtimeShell}
-            set -o errexit
-            set -o nounset
-            set -o pipefail
-          ''
-        ]
-        ++ 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];
+    pkgs.writeShellApplication {
+      name = "nvim";
+      runtimeInputs = cfg.paths;
+      runtimeEnv =
+        {
+          NVIM_RPLUGIN_MANIFEST = "${config.neovim.build.rplugin}/rplugin.vim";
+        }
+        // (cfg.env or {});
       meta.mainProgram = "nvim";
-      passthru = {
+      text = ''
+        ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
+      '';
+      derivationArgs.passthru = {
         inherit (config.neovim.build) initlua plugins;
       };
     };

From 70b5d6263b635ca470db73fc9c2e6b8d1f910ca5 Mon Sep 17 00:00:00 2001
From: winston <hey@winston.sh>
Date: Tue, 12 Mar 2024 03:01:58 +0100
Subject: [PATCH 2/5] refactor: remove `meta.mainProgram` & flip env attrset

already set by `writeTextFile`:
https://github.com/NixOS/nixpkgs/blob/52544c4a0a84552db4013a8858ade52eaf7ff0ca/pkgs/build-support/trivial-builders/default.nix#L167
---
 modules/default.nix | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/modules/default.nix b/modules/default.nix
index 042121e..d5024df 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -17,11 +17,10 @@
       name = "nvim";
       runtimeInputs = cfg.paths;
       runtimeEnv =
-        {
+        (cfg.env or {})
+        // {
           NVIM_RPLUGIN_MANIFEST = "${config.neovim.build.rplugin}/rplugin.vim";
-        }
-        // (cfg.env or {});
-      meta.mainProgram = "nvim";
+        };
       text = ''
         ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
       '';

From f1143483c7759afb74cbc4f7a4f3217ada2171da Mon Sep 17 00:00:00 2001
From: winston <hey@winston.sh>
Date: Tue, 12 Mar 2024 08:53:44 +0100
Subject: [PATCH 3/5] fix: use previous version of settings `$PATH`

---
 modules/default.nix | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/modules/default.nix b/modules/default.nix
index d5024df..4824319 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -4,7 +4,7 @@
   ...
 }: let
   inherit (flake-parts-lib) mkPerSystemOption;
-  inherit (lib) mkOption types;
+  inherit (lib) makeBinPath mkOption types unique;
 
   mkNeovimEnv = {
     config,
@@ -15,15 +15,19 @@
   in
     pkgs.writeShellApplication {
       name = "nvim";
-      runtimeInputs = cfg.paths;
       runtimeEnv =
         (cfg.env or {})
         // {
           NVIM_RPLUGIN_MANIFEST = "${config.neovim.build.rplugin}/rplugin.vim";
         };
-      text = ''
-        ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
-      '';
+      text =
+        lib.optionalString (cfg.paths != [])
+        ''
+          export PATH="$PATH:${makeBinPath (unique cfg.paths)}"
+        ''
+        + ''
+          ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
+        '';
       derivationArgs.passthru = {
         inherit (config.neovim.build) initlua plugins;
       };

From 2c4fb982961eb0782fb5a3f73469a450969c9f19 Mon Sep 17 00:00:00 2001
From: Will Ruggiano <wmruggiano@gmail.com>
Date: Tue, 12 Mar 2024 18:59:38 -0600
Subject: [PATCH 4/5] don't use runtimeEnv, update workflows

---
 .github/workflows/check.yaml          | 10 +++-------
 .github/workflows/update-example.yaml |  3 ++-
 flake.nix                             | 15 +++++++++++++++
 modules/default.nix                   | 23 +++++++++++------------
 4 files changed, 31 insertions(+), 20 deletions(-)

diff --git a/.github/workflows/check.yaml b/.github/workflows/check.yaml
index 18d5ea8..76761ae 100644
--- a/.github/workflows/check.yaml
+++ b/.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
diff --git a/.github/workflows/update-example.yaml b/.github/workflows/update-example.yaml
index 93d7e54..7df29fd 100644
--- a/.github/workflows/update-example.yaml
+++ b/.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 'willruggiano@users.noreply.github.com'
diff --git a/flake.nix b/flake.nix
index 0b471ed..0e433b9 100644
--- a/flake.nix
+++ b/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 = ''
diff --git a/modules/default.nix b/modules/default.nix
index 4824319..39437ea 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -4,7 +4,7 @@
   ...
 }: let
   inherit (flake-parts-lib) mkPerSystemOption;
-  inherit (lib) makeBinPath mkOption types unique;
+  inherit (lib) concatStringsSep makeBinPath mapAttrsToList mkOption optional optionals types unique;
 
   mkNeovimEnv = {
     config,
@@ -15,19 +15,18 @@
   in
     pkgs.writeShellApplication {
       name = "nvim";
-      runtimeEnv =
-        (cfg.env or {})
-        // {
-          NVIM_RPLUGIN_MANIFEST = "${config.neovim.build.rplugin}/rplugin.vim";
-        };
-      text =
-        lib.optionalString (cfg.paths != [])
-        ''
+      text = concatStringsSep "\n" (
+        optionals (cfg.env != {}) (mapAttrsToList (name: value: ''export ${name}="''${${name}:-${toString value}}"'') cfg.env)
+        ++ optional (cfg.paths != []) ''
           export PATH="$PATH:${makeBinPath (unique cfg.paths)}"
         ''
-        + ''
-          ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
-        '';
+        ++ [
+          ''
+            export NVIM_RPLUGIN_MANIFEST="${config.neovim.build.rplugin}/rplugin.vim"
+            ${cfg.package}/bin/nvim -u ${cfg.build.initlua} "$@"
+          ''
+        ]
+      );
       derivationArgs.passthru = {
         inherit (config.neovim.build) initlua plugins;
       };

From 9550fa31a416e4a80b84f79df731af2e76758a9f Mon Sep 17 00:00:00 2001
From: Will Ruggiano <wmruggiano@gmail.com>
Date: Tue, 12 Mar 2024 19:05:06 -0600
Subject: [PATCH 5/5] add some explanatory comments

---
 modules/default.nix | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/modules/default.nix b/modules/default.nix
index 39437ea..648f588 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -12,11 +12,18 @@
     ...
   }: let
     cfg = config.neovim;
+    toEnvVar = name: value: ''export ${name}="''${${name}:-${toString value}}"'';
   in
     pkgs.writeShellApplication {
       name = "nvim";
       text = concatStringsSep "\n" (
-        optionals (cfg.env != {}) (mapAttrsToList (name: value: ''export ${name}="''${${name}:-${toString value}}"'') cfg.env)
+        # 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)}"
         ''