From 4b3b67fb6f618726aecea1f07b35c57e4963ea8c Mon Sep 17 00:00:00 2001
From: Matt Sturgeon <matt@sturgeon.me.uk>
Date: Sat, 21 Dec 2024 13:40:16 +0000
Subject: [PATCH] lib: make overrideable & access via flake

Add a non-system specific `<flake>.lib.nixvim` output, which is
equivalent to the existing `<flake>.lib.<system>.helpers` output.

This is now also wrapped with `lib.makeOverridable` to allow overriding
the function args used to construct the nixvim-lib.

Consistently access nixvim-lib via the new flake output, overriding
where necessary.
---
 docs/default.nix           |  2 +-
 flake-modules/lib.nix      | 41 +++++++++++++++++++++-----------------
 flake-modules/packages.nix |  7 ++++++-
 lib/tests.nix              |  4 +---
 wrappers/_shared.nix       |  8 +-------
 wrappers/standalone.nix    |  6 +-----
 6 files changed, 33 insertions(+), 35 deletions(-)

diff --git a/docs/default.nix b/docs/default.nix
index cfe77c61..45ae3b86 100644
--- a/docs/default.nix
+++ b/docs/default.nix
@@ -1,4 +1,5 @@
 {
+  helpers,
   system,
   nixpkgs,
   nuschtosSearch,
@@ -7,7 +8,6 @@ let
   # We overlay a few tweaks into pkgs, for use in the docs
   pkgs = import ./pkgs.nix { inherit system nixpkgs; };
   inherit (pkgs) lib;
-  helpers = import ../lib { inherit lib; };
 
   nixvimPath = toString ./..;
 
diff --git a/flake-modules/lib.nix b/flake-modules/lib.nix
index 2d71177f..8fce9a81 100644
--- a/flake-modules/lib.nix
+++ b/flake-modules/lib.nix
@@ -6,24 +6,29 @@
   ...
 }:
 {
-  _module.args.helpers = import ../lib {
-    inherit lib;
-    flake = self;
+  # Expose lib as a flake-parts module arg
+  _module.args = {
+    helpers = self.lib.nixvim;
   };
 
-  # TODO: output lib without pkgs at the top-level
-  flake.lib = lib.genAttrs config.systems (
-    lib.flip withSystem (
-      { pkgs, ... }:
-      {
-        # NOTE: this is the publicly documented flake output we've had for a while
-        check = import ../lib/tests.nix { inherit self lib pkgs; };
-        # TODO: no longer needs to be per-system
-        helpers = import ../lib {
-          inherit lib;
-          flake = self;
-        };
-      }
-    )
-  );
+  # Public `lib` flake output
+  flake.lib =
+    {
+      nixvim = lib.makeOverridable (import ../lib) {
+        inherit lib;
+        flake = self;
+      };
+    }
+    // lib.genAttrs config.systems (
+      lib.flip withSystem (
+        { pkgs, ... }:
+        {
+          # NOTE: this is the publicly documented flake output we've had for a while
+          check = pkgs.callPackage ../lib/tests.nix { inherit self; };
+
+          # NOTE: no longer needs to be per-system
+          helpers = self.lib.nixvim;
+        }
+      )
+    );
 }
diff --git a/flake-modules/packages.nix b/flake-modules/packages.nix
index 76e5ca3e..3916b0b1 100644
--- a/flake-modules/packages.nix
+++ b/flake-modules/packages.nix
@@ -1,4 +1,8 @@
-{ inputs, ... }:
+{
+  inputs,
+  helpers,
+  ...
+}:
 {
   perSystem =
     {
@@ -9,6 +13,7 @@
     }:
     {
       packages = import ../docs {
+        inherit helpers;
         inherit system;
         inherit (inputs) nixpkgs;
         inherit (inputs') nuschtosSearch;
diff --git a/lib/tests.nix b/lib/tests.nix
index d4b46e95..e77e43d2 100644
--- a/lib/tests.nix
+++ b/lib/tests.nix
@@ -46,9 +46,7 @@ let
     }@args:
     let
       # NOTE: we are importing this just for evalNixvim
-      helpers = import ../lib {
-        inherit lib;
-        flake = self;
+      helpers = self.lib.nixvim.override {
         # TODO: deprecate helpers.enableExceptInTests,
         # add a context option e.g. `config.isTest`?
         _nixvimTests = true;
diff --git a/wrappers/_shared.nix b/wrappers/_shared.nix
index 9d93f9ea..010cc290 100644
--- a/wrappers/_shared.nix
+++ b/wrappers/_shared.nix
@@ -59,13 +59,7 @@ in
   config = mkMerge [
     {
       # Make our lib available to the host modules
-      # NOTE: user-facing so we must include the legacy `pkgs` argument
-      lib.nixvim = lib.mkDefault (
-        import ../lib {
-          inherit lib;
-          flake = self;
-        }
-      );
+      lib.nixvim = lib.mkDefault self.lib.nixvim;
 
       # Make nixvim's "extended" lib available to the host's module args
       _module.args.nixvimLib = lib.mkDefault config.lib.nixvim.extendedLib;
diff --git a/wrappers/standalone.nix b/wrappers/standalone.nix
index 61eac95c..241b715c 100644
--- a/wrappers/standalone.nix
+++ b/wrappers/standalone.nix
@@ -9,11 +9,7 @@ default_pkgs: self:
 }:
 let
   # NOTE: we are importing this just for evalNixvim
-  helpers = import ../lib {
-    inherit lib _nixvimTests;
-    flake = self;
-  };
-
+  helpers = self.lib.nixvim.override { inherit _nixvimTests; };
   inherit (helpers.modules) evalNixvim;
 
   mkNvim =