fix systemsFromFile

- make use of config.projectRoot to ge relative path of systems file

docs/src/intro.md

@@ -26,6 +26,5 @@ The intention is to integrate many existing 2nix converters into this framework,
 
 - [Architectural Considerations](./intro/architectural-considerations.md)
 - [Potential impact on nixpkgs](./intro/nixpkgs-improvements.md)
-- [Development Roundups](./development-roundups.md)
 
 [glossary]: https://nixos.wiki/wiki/Glossary "glossary"

src/lib.nix

@@ -70,6 +70,7 @@
     source,
     pkgs ? null,
     systems ? [],
+    systemsFromFile ? null,
     config ? {},
     inject ? {},
     pname ? throw "Please pass `pname` to makeFlakeOutputs",
@@ -77,6 +78,11 @@
     settings ? [],
     sourceOverrides ? oldSources: {},
   } @ args: let
+    systems =
+      if systemsFromFile == null
+      then args.systems or []
+      else dlib.systemsFromFile systemsFromFile;
+
     allPkgs = makeNixpkgs pkgs systems;
 
     config = loadConfig (args.config or {});
@@ -179,7 +185,6 @@
     flakeOutputs;
 in rec {
   inherit init makeFlakeOutputs makeFlakeOutputsForIndexes;
-  inherit (dlib) systemsFromFile;
   dlib = import ./lib {
     inherit lib;
     config = (import ./utils/config.nix).loadConfig {};

src/lib/default.nix

@@ -298,12 +298,15 @@
 
   systemsFromFile = file:
     if ! l.pathExists file
-    then
+    then let
+      relPathFile =
+        l.removePrefix (l.toString config.projectRoot) (l.toString file);
+    in
       throw ''
         The system for your flake.nix is not initialized yet.
         Please execute the following command to initialize it:
 
-        nix eval --impure --raw --expr 'builtins.currentSystem' > ./${l.baseNameOf file} && git add ./${l.baseNameOf file}
+        nix eval --impure --raw --expr 'builtins.currentSystem' > .${relPathFile} && git add .${relPathFile}
       ''
     else l.filter (l: l != "") (l.splitString "\n" (l.readFile file));
 

templates/simple/flake.nix

@@ -2,8 +2,7 @@
   inputs.dream2nix.url = "github:nix-community/dream2nix";
   outputs = inp:
     inp.dream2nix.lib.makeFlakeOutputs {
-      # modify according to your supported systems
-      systems = inp.dream2nix.lib.systemsFromFile ./nix_systems;
+      systemsFromFile = ./nix_systems;
       config.projectRoot = ./.;
       source = ./.;
     };