racket-minimal: add info for config dir and main collection dir

pkgs/development/interpreters/racket/minimal.nix

@@ -86,12 +86,11 @@ stdenv.mkDerivation (finalAttrs: {
   dontStrip = isDarwin;
 
   passthru = {
-    tests = builtins.mapAttrs (name: path: callPackage path { racket = finalAttrs.finalPackage; }) {
-      write-greeting = ./tests/write-greeting.nix;
-      get-current-launcher-variant = ./tests/get-current-launcher-variant.nix;
-      nix-write-script = ./tests/nix-write-script.nix;
-    };
+    # Useful information #
+    configDir = "etc/racket";
+    collectsDir = "share/racket/collects";
 
+    # Functionalities #
     writeScript =
       nameOrPath:
       {
@@ -106,6 +105,17 @@ stdenv.mkDerivation (finalAttrs: {
         }
       ) nameOrPath;
     writeScriptBin = name: finalAttrs.passthru.writeScript "/bin/${name}";
+
+    # Tests #
+    tests = builtins.mapAttrs (name: path: callPackage path { racket = finalAttrs.finalPackage; }) {
+      ## Basic ##
+      write-greeting = ./tests/write-greeting.nix;
+      get-current-launcher-variant = ./tests/get-current-launcher-variant.nix;
+
+      ## Nixpkgs supports ##
+      nix-write-script = ./tests/nix-write-script.nix;
+      nix-dirs = ./tests/nix-dirs.nix;
+    };
   };
 
   meta = {

pkgs/development/interpreters/racket/tests/nix-dirs.nix

@@ -0,0 +1,40 @@
+{
+  lib,
+  runCommandLocal,
+  racket,
+}:
+
+let
+  expectation = lib.concatMapStringsSep ":" (subDir: "${racket}/${subDir}/") (
+    with racket.passthru;
+    [
+      configDir
+      collectsDir
+    ]
+  );
+in
+
+runCommandLocal "racket-test-nix-dirs"
+  {
+    nativeBuildInputs = [ racket ];
+  }
+  ''
+    expectation="${expectation}"
+
+    racket -f - <<EOF
+    (require setup/dirs)
+    (with-output-to-file (getenv "out")
+      (lambda ()
+        (displayln (string-join (map path->string
+                                     (list (find-config-dir)
+                                           (find-collects-dir)))
+                                ":"))))
+    EOF
+
+    output="$(cat $out)"
+
+    if test "$output" != "$expectation"; then
+        echo "output mismatch: expected ''${expectation}, but got ''${output}"
+        exit 1
+    fi
+  ''