Tidy up project modules

hix/project.nix

@@ -8,53 +8,13 @@
 , shell ? null
 , ...}@commandArgs:
 let
-  hixProject = {
-        options = {
-          haskellNix = lib.mkOption {
-            type = lib.types.unspecified;
-            default = null;
-          };
-          nixpkgsPin = lib.mkOption {
-            type = lib.types.str;
-            default = "nixpkgs-unstable";
-          };
-          nixpkgs = lib.mkOption {
-            type = lib.types.unspecified;
-            default = null;
-          };
-          nixpkgsArgs = lib.mkOption {
-            type = lib.types.unspecified;
-            default = null;
-          };
-          overlays = lib.mkOption {
-            type = lib.types.unspecified;
-            default = [];
-          };
-          pkgs = lib.mkOption {
-            type = lib.types.unspecified;
-            default = null;
-          };
-          project = lib.mkOption {
-            type = lib.types.unspecified;
-            default = null;
-          };
-        };
-      };
-  hixDefaults = { compiler-nix-name = lib.mkDefault "ghc8105"; };
   inherit ((lib.evalModules {
     modules = [
-      hixProject
-      {
-        options = {
-          projectFileName = lib.mkOption {
-            type = lib.types.nullOr lib.types.str;
-            default = null;
-          };
-        };
-      }
-      (import ../modules/project.nix)
+      (import ../modules/project-common.nix)
       (import ../modules/stack-project.nix)
       (import ../modules/cabal-project.nix)
+      (import ../modules/project.nix)
+      (import ../modules/hix-project.nix)
       projectDefaults
       commandArgs'
       { _module.args.pkgs = {}; }
@@ -81,19 +41,11 @@ let
   projectDefaults = importDefaults (toString (src.origSrcSubDir or src) + "/nix/hix.nix");
   inherit ((lib.evalModules {
     modules = [
-      hixProject
-      {
-        options = {
-          projectFileName = lib.mkOption {
-            type = lib.types.nullOr lib.types.str;
-            default = null;
-          };
-        };
-      }
-      (import ../modules/project.nix)
+      (import ../modules/project-common.nix)
       (import ../modules/stack-project.nix)
       (import ../modules/cabal-project.nix)
-      hixDefaults
+      (import ../modules/project.nix)
+      (import ../modules/hix-project.nix)
       userDefaults
       projectDefaults
       commandArgs'
@@ -106,8 +58,7 @@ let
         };
         pkgs = import config.nixpkgs config.nixpkgsArgs;
         project = config.pkgs.haskell-nix.project [
-            hixProject
-            hixDefaults
+            (import ../modules/hix-project.nix)
             userDefaults
             projectDefaults
             commandArgs'

lib/default.nix

@@ -341,7 +341,7 @@ in {
       (lib.evalModules {
         modules = (if builtins.isList m then m else [m]) ++ [
           # Include ../modules/cabal-project.nix or ../modules/stack-project.nix
-          (import ../modules/project.nix)
+          (import ../modules/project-common.nix)
           (import projectType)
           # Pass the pkgs to the modules
           ({ config, lib, ... }: {

modules/cabal-project.nix

@@ -129,17 +129,5 @@ in {
       type = nullOr (listOf unspecified);
       default = [];
     };
-
-    # Default shell arguments
-    shell = mkOption {
-      # TODO make this a submodule
-      type = unspecified;
-      default = {};
-      description = ''
-        Arguments to use for the default shell `p.shell` (these are passed to p.shellFor).
-        For instance to include `cabal` and `ghcjs` support use
-          shell = { tools.cabal = {}; crossPlatforms = p: [ p.ghcjs ]; }
-      '';
-    };
   };
 }

modules/hix-project.nix

@@ -0,0 +1,40 @@
+{ lib, ... }: {
+  _file = "haskell.nix/modules/hix-project.nix";
+  options = {
+    # These are options that only the Hix command wrappers use. If you make a flake
+    # with `haskell-nix.hix.project`, then they are ignored.
+    haskellNix = lib.mkOption {
+      type = lib.types.unspecified;
+      default = null;
+    };
+    nixpkgsPin = lib.mkOption {
+      type = lib.types.str;
+      default = "nixpkgs-unstable";
+    };
+    nixpkgs = lib.mkOption {
+      type = lib.types.unspecified;
+      default = null;
+    };
+    nixpkgsArgs = lib.mkOption {
+      type = lib.types.unspecified;
+      default = null;
+    };
+    overlays = lib.mkOption {
+      type = lib.types.unspecified;
+      default = [];
+    };
+    pkgs = lib.mkOption {
+      type = lib.types.unspecified;
+      default = null;
+    };
+    project = lib.mkOption {
+      type = lib.types.unspecified;
+      default = null;
+    };
+  };
+
+  # Default values for other project options (things that do not have defaults for non hix projects)
+  config = {
+    compiler-nix-name = lib.mkDefault "ghc8105";
+  };
+}

modules/project-common.nix

@@ -0,0 +1,28 @@
+{ lib, ... }:
+with lib;
+with lib.types;
+{
+  _file = "haskell.nix/modules/project-common.nix";
+  options = {
+    # Used by callCabalProjectToNix and callStackToNix
+    name = mkOption {
+      type = nullOr str;
+      default = "haskell-project"; # TODO figure out why `config.src.name or null` breaks hix;
+      description = "Optional name for better error messages";
+    };
+    src = mkOption {
+      type = either path package;
+    };
+    # Default shell arguments
+    shell = mkOption {
+      # TODO make this a submodule
+      type = unspecified;
+      default = {};
+      description = ''
+        Arguments to use for the default shell `p.shell` (these are passed to p.shellFor).
+        For instance to include `cabal` and `ghcjs` support use
+          shell = { tools.cabal = {}; crossPlatforms = p: [ p.ghcjs ]; }
+      '';
+    };
+  };
+}

modules/project.nix

@@ -1,23 +1,9 @@
-{ lib, config, pkgs, haskellLib, ... }:
-with lib;
-with types;
-let readIfExists = src: fileName:
-      let origSrcDir = src.origSrcSubDir or src;
-      in
-        if builtins.elem ((__readDir origSrcDir)."${fileName}" or "") ["regular" "symlink"]
-          then __readFile (origSrcDir + "/${fileName}")
-          else null;
-in {
+{ lib, ... }: {
   _file = "haskell.nix/modules/project.nix";
   options = {
-    # Used by callCabalProjectToNix and callStackToNix
-    name = mkOption {
-      type = nullOr str;
-      default = "haskell-project"; # TODO figure out why `config.src.name or null` breaks hix;
-      description = "Optional name for better error messages";
-    };
-    src = mkOption {
-      type = either path package;
+    projectFileName = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
     };
   };
-}
+}

modules/stack-project.nix

@@ -101,17 +101,5 @@ with types;
       default = null;
       description = "Deprecated in favour of `compiler-nix-name`";
     };
-
-    # Default shell arguments
-    shell = mkOption {
-      # TODO make this a submodule
-      type = unspecified;
-      default = {};
-      description = ''
-        Arguments to use for the default shell `p.shell` (these are passed to p.shellFor).
-        For instance to include `cabal` and `ghcjs` support use
-          shell = { tools.cabal = {}; crossPlatforms = p: [ p.ghcjs ]; }
-      '';
-    };
   };
 }

overlays/haskell.nix

@@ -814,17 +814,10 @@ final: prev: {
             projectModule' = if builtins.isList projectModule then projectModule else [projectModule];
             inherit ((final.lib.evalModules {
               modules = [
-                {
-                  options = {
-                    projectFileName = final.lib.mkOption {
-                      type = final.lib.types.nullOr final.lib.types.string;
-                      default = null;
-                    };
-                  };
-                }
-                (import ../modules/project.nix)
+                (import ../modules/project-common.nix)
                 (import ../modules/stack-project.nix)
                 (import ../modules/cabal-project.nix)
+                (import ../modules/project.nix)
               ] ++ projectModule';
             }).config) src projectFileName;
             dir = __readDir (src.origSrcSubDir or src);

overlays/hix.nix

@@ -12,17 +12,11 @@ final: prev: { haskell-nix = prev.haskell-nix // { hix = {
       hixDefaults = { compiler-nix-name = lib.mkDefault "ghc8105"; };
       inherit ((lib.evalModules {
         modules = [
-          {
-            options = {
-              projectFileName = lib.mkOption {
-                type = lib.types.nullOr lib.types.str;
-                default = null;
-              };
-            };
-          }
-          (import ../modules/project.nix)
+          (import ../modules/project-common.nix)
           (import ../modules/stack-project.nix)
           (import ../modules/cabal-project.nix)
+          (import ../modules/project.nix)
+          (import ../modules/hix-project.nix)
           projectDefaults
           commandArgs'
           { _module.args.pkgs = {}; }
@@ -42,7 +36,7 @@ final: prev: { haskell-nix = prev.haskell-nix // { hix = {
           else import src;
       projectDefaults = importDefaults (toString (src.origSrcSubDir or src) + "/nix/hix.nix");
     in final.haskell-nix.project [
-            hixDefaults
+            (import ../modules/hix-project.nix)
             projectDefaults
             commandArgs'
             {