style(flake)!: manually import lib flake module

- Also make `lib` an `internal` option
- Unify let blocks and move them under `imports`
  (makes it clear where `config.lib` comes from)
- Fix a minor typo

modules/flake/configurations/default-generators.nix

@@ -5,9 +5,9 @@ let
     and
     hasFiles
     hasDirectories
-    configuration-type-to-outputs-modules;
-in
-let
+    configuration-type-to-outputs-modules
+    ;
+
   # `pkgs` with flake's overlays
   # NOTE: done here to avoid infinite recursion
   pkgs' = system:

modules/flake/configurations/default.nix

@@ -1,21 +1,19 @@
 { lib, config, self, inputs, withSystem, ... }:
 
-let
-  inherit (config.lib)
-    and
-    hasFiles
-    hasDirectories
-    recurseDir
-    kebabToCamel
-    configuration-type-to-outputs-modules;
-in
 {
   imports = [
+    ../lib
     ./default-generators.nix
   ];
 
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
+    inherit (config.lib)
+      recurseDir
+      kebabToCamel
+      ;
   in {
     auto.configurations = lib.mkOption {
       description = ''

modules/flake/lib/default.nix

@@ -6,9 +6,12 @@
   ];
 
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
   in {
     lib = lib.mkOption {
+      internal = true;
       type = types.unspecified;
     };
   };

modules/flake/lib/things.nix

@@ -1,14 +1,13 @@
 { lib, config, self, inputs, ... }:
 
-let
-  inherit (config.lib)
-    and
-    eq
-    hasFiles
-    ;
-in
 {
-  config.lib = rec {
+  config.lib = let
+    inherit (config.lib)
+      and
+      eq
+      hasFiles
+      ;
+  in rec {
     # Try to passthru `inputs` by default
     defaultThingHandle = { raw, thingType }: name: result: let
       thing =

modules/flake/modules/default.nix

@@ -1,21 +1,24 @@
 { lib, config, self, inputs, ... }:
 
-let
-  inherit (config.lib)
-    createThings
-    kebabToCamel;
-in
-let
-  # Modules helpers
-  createModules = baseDir:
-    createThings {
-      inherit baseDir;
-      thingType = "module";
-    };
-in
 {
+  imports = [
+    ../lib
+  ];
+
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
+    inherit (config.lib)
+      createThings
+      kebabToCamel
+      ;
+
+    createModules = baseDir:
+      createThings {
+        inherit baseDir;
+        thingType = "module";
+      };
   in {
     auto.modules = lib.mkOption {
       description = ''
@@ -76,7 +79,6 @@ in
                       (createModules dir);
                 };
               };
-              config = {};
             }));
             # TODO: put in a more visible place
             default = {

modules/flake/overlays/default.nix

@@ -1,19 +1,23 @@
 { lib, config, self, inputs, ... }:
 
-let
-  inherit (config.lib)
-    createThings;
-in
-let
-  createOverlays = baseDir:
-    createThings {
-      inherit baseDir;
-      thingType = "overlay";
-    };
-in
 {
+  imports = [
+    ../lib
+  ];
+
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
+    inherit (config.lib)
+      createThings
+      ;
+
+    createOverlays = baseDir:
+      createThings {
+        inherit baseDir;
+        thingType = "overlay";
+      };
   in {
     auto.overlays = lib.mkOption {
       description = ''

modules/flake/packages/default.nix

@@ -1,23 +1,27 @@
 { lib, config, self, inputs, ... }:
 
-let
-  inherit (config.lib)
-    createThings;
-in
-let
-  createPackages = baseDir:
-    createThings {
-      inherit baseDir;
-      thingType = "package";
-      raw = false;
-      extras.systems = {
-        default = lib.const true;
-      };
-    };
-in
 {
+  imports = [
+    ../lib
+  ];
+
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
+    inherit (config.lib)
+      createThings
+      ;
+
+    createPackages = baseDir:
+      createThings {
+        inherit baseDir;
+        thingType = "package";
+        raw = false;
+        extras.systems = {
+          default = lib.const true;
+        };
+      };
   in {
     auto.packages = lib.mkOption {
       description = ''

modules/flake/pkgs/default.nix

@@ -4,7 +4,7 @@
   perSystem = { system, ... }: {
     _module.args.pkgs = import inputs.nixpkgs {
       inherit system;
-      # WARN: not including `self.packages` overylay
+      # WARN: not including `self.packages` overlay
       #       because it causes an infinite recursion
       overlays = lib.attrValues self.overlays ++ [
         inputs.neovim-nightly-overlay.overlays.default

modules/flake/shells/default.nix

@@ -1,23 +1,27 @@
 { lib, config, self, inputs, ... }:
 
-let
-  inherit (config.lib)
-    createThings;
-in
-let
-  createDevShells = baseDir:
-    createThings {
-      inherit baseDir;
-      thingType = "devShell";
-      raw = false;
-      extras.systems = {
-        default = lib.const true;
-      };
-    };
-in
 {
+  imports = [
+    ../lib
+  ];
+
   options = let
-    inherit (lib) types;
+    inherit (lib)
+      types
+      ;
+    inherit (config.lib)
+      createThings
+      ;
+
+    createDevShells = baseDir:
+      createThings {
+        inherit baseDir;
+        thingType = "devShell";
+        raw = false;
+        extras.systems = {
+          default = lib.const true;
+        };
+      };
   in {
     auto.devShells = lib.mkOption {
       description = ''