lib/modules: defaultPkgs -> pkgsPath

Author: MattSturgeon

docs/default.nix

@@ -7,7 +7,10 @@ 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; };
+  helpers = import ../lib {
+    inherit lib;
+    pkgsPath = nixpkgs;
+  };
 
   nixvimPath = toString ./..;
 
@@ -34,9 +37,6 @@ let
     };
 
   evaledModules = helpers.modules.evalNixvim {
-    extraSpecialArgs = {
-      defaultPkgs = pkgs;
-    };
     modules = [
       { isDocs = true; }
       { nixpkgs.pkgs = lib.mkDefault pkgs; }

flake-modules/legacy-packages.nix

@@ -16,9 +16,6 @@
           modules = [
             { nixpkgs.pkgs = lib.mkDefault pkgs; }
           ];
-          extraSpecialArgs = {
-            defaultPkgs = pkgs;
-          };
           check = false;
         };
       };

flake-modules/lib.nix

@@ -1,5 +1,6 @@
 {
   config,
+  inputs,
   lib,
   withSystem,
   ...
@@ -13,9 +14,15 @@
       { pkgs, ... }:
       {
         # NOTE: this is the publicly documented flake output we've had for a while
-        check = import ../lib/tests.nix { inherit lib pkgs; };
+        check = import ../lib/tests.nix {
+          inherit lib pkgs;
+          pkgsPath = inputs.nixpkgs;
+        };
         # NOTE: user-facing so we must include the legacy `pkgs` argument
-        helpers = import ../lib { inherit lib pkgs; };
+        helpers = import ../lib {
+          inherit lib pkgs;
+          pkgsPath = inputs.nixpkgs;
+        };
       }
     )
   );

lib/default.nix

@@ -1,5 +1,7 @@
 {
   pkgs ? null,
+  # `pkgsPath` is required for evalNixvim's default specialArgs
+  pkgsPath ? pkgs.path or null,
   lib ? pkgs.lib,
   _nixvimTests ? false,
   ...
@@ -38,24 +40,12 @@ lib.fix (
     extendedLib = call ./extend-lib.nix { inherit lib; };
     keymaps = call ./keymap-helpers.nix { };
     lua = call ./to-lua.nix { };
+    modules = call ./modules.nix { inherit pkgsPath; };
     neovim-plugin = call ./neovim-plugin.nix { };
     options = call ./options.nix { };
     utils = call ./utils.nix { inherit _nixvimTests; };
     vim-plugin = call ./vim-plugin.nix { };
 
-    # Handle modules, which currently requires a `defaultPkgs` specialArg
-    # FIXME: our minimal specialArgs should not need `pkgs`
-    modules = call ./modules.nix { } // {
-      # Minimal specialArgs required to evaluate nixvim modules
-      specialArgs = self.modules.specialArgsWith {
-        defaultPkgs =
-          if pkgs == null then
-            throw "`modules.specialArgs` cannot currently be used when nixvim's lib is built without a `pkgs` instance. This will be resolved in the future."
-          else
-            pkgs;
-      };
-    };
-
     # Handle builders, which has some deprecated stuff that depends on `pkgs`
     builders = builders // deprecatedBuilders;
     inherit (self.builders)

lib/modules.nix

@@ -1,15 +1,29 @@
 {
   lib,
   self,
+  pkgsPath,
 }:
 rec {
+  # Minimal specialArgs required to evaluate nixvim modules
+  specialArgs = self.modules.specialArgsWith { };
+
   # Build specialArgs for evaluating nixvim modules
   specialArgsWith =
-    # TODO: switch defaultPkgs -> pkgsPath (i.e. pkgs.path or inputs.nixvim)
-    # FIXME: Ideally, we should not require callers to pass in _anything_ specific
-    { defaultPkgs, ... }@extraSpecialArgs:
+    extraSpecialArgs:
     {
-      inherit lib defaultPkgs;
+      inherit lib;
+      # TODO: find a better way to handle pkgsPath 🤔
+      # - Maybe nixvim's lib should always be provided with `pkgsPath`?
+      # - Or maybe it can evaluate it internally, by reading `flake.lock`?
+      pkgsPath =
+        if pkgsPath == null then
+          throw ''
+            `modules.specialArgs` or `modules.evalNixvim` was used without a `pkgsPath`.
+            You can resolve this by either specifying `pkgsPath` using `extraSpecialArgs` or `modules.specialArgsWith`,
+            or by using a nixvim lib instance evaluated with `pkgsPath` supplied.
+          ''
+        else
+          builtins.toString pkgsPath;
       # TODO: deprecate `helpers`
       helpers = self;
     }

lib/tests.nix

@@ -1,5 +1,6 @@
 {
   pkgs,
+  pkgsPath ? pkgs.path,
   lib ? pkgs.lib,
   ...
 }:
@@ -46,7 +47,7 @@ let
     let
       helpers = import ../lib {
         # NOTE: must match the user-facing functions, so we still include the `pkgs` argument
-        inherit pkgs lib;
+        inherit pkgs pkgsPath lib;
         # TODO: deprecate helpers.enableExceptInTests,
         # add a context option e.g. `config.isTest`?
         _nixvimTests = true;
@@ -65,9 +66,7 @@ let
           # FIXME: don't do this by default
           { nixpkgs.pkgs = lib.mkDefault pkgs; }
         ];
-        extraSpecialArgs = {
-          defaultPkgs = pkgs;
-        } // extraSpecialArgs;
+        inherit extraSpecialArgs;
         # Don't check assertions/warnings while evaluating nixvim config
         # We'll let the test derivation handle that
         check = false;

modules/misc/default.nix

@@ -1,14 +1,12 @@
-{ defaultPkgs, ... }:
-let
-  # We can't use config._module.args to define imports,
-  # so we're forced to use specialArgs.defaultPkgs's path
-  nixosModules = defaultPkgs.path + "/nixos/modules/";
-in
+{ pkgsPath, ... }:
 {
   imports = [
     ./context.nix
     ./nixvim-info.nix
-    (nixosModules + "/misc/assertions.nix")
-    (nixosModules + "/misc/meta.nix")
+    # FIXME: this is the only reason `pkgsPath` needs to be a specialArg.
+    # It also fails when `pkgsPath` is a string with context because meta.nix
+    # tries to use the _file string somewhere that string-context isn't supported 😭
+    (pkgsPath + "/nixos/modules/misc/assertions.nix")
+    (builtins.unsafeDiscardStringContext pkgsPath + "/nixos/modules/misc/meta.nix")
   ];
 }

wrappers/_shared.nix

@@ -1,4 +1,6 @@
 {
+  # This flake
+  flake,
   # Option path where extraFiles should go
   filesOpt ? null,
   # Filepath prefix to apply to extraFiles
@@ -47,7 +49,12 @@ in
     {
       # 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 pkgs lib; });
+      lib.nixvim = lib.mkDefault (
+        import ../lib {
+          inherit pkgs lib;
+          pkgsPath = flake.inputs.nixpkgs;
+        }
+      );
 
       # Make nixvim's "extended" lib available to the host's module args
       _module.args.nixvimLib = lib.mkDefault config.lib.nixvim.extendedLib;

wrappers/darwin.nix

@@ -26,7 +26,6 @@ in
       type = types.submoduleWith {
         shorthandOnlyDefinesConfig = true;
         specialArgs = config.lib.nixvim.modules.specialArgsWith {
-          defaultPkgs = pkgs;
           darwinConfig = config;
         };
         modules = [
@@ -39,7 +38,7 @@ in
     };
   };
 
-  imports = [ (import ./_shared.nix { }) ];
+  imports = [ (import ./_shared.nix { inherit flake; }) ];
 
   config = mkIf cfg.enable (mkMerge [
     {

wrappers/hm.nix

@@ -25,7 +25,6 @@ in
       type = types.submoduleWith {
         shorthandOnlyDefinesConfig = true;
         specialArgs = config.lib.nixvim.modules.specialArgsWith {
-          defaultPkgs = pkgs;
           hmConfig = config;
         };
         modules = [
@@ -40,6 +39,7 @@ in
 
   imports = [
     (import ./_shared.nix {
+      inherit flake;
       filesOpt = [
         "xdg"
         "configFile"