lib.packagesFromDirectoryRecursive: default to creating new scopes wh…

…en `newScope` is provided
NixOS · Dec 3, 2024 · ecca66e · ecca66e
1 parent c682f05
commit ecca66e
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Showing 2 changed files with 20 additions and 13 deletions.
diff --git a/lib/filesystem.nix b/lib/filesystem.nix
@@ -314,6 +314,7 @@ in
     ```
     packagesFromDirectoryRecursive :: (args :: {
       callPackage :: Path -> {} -> a,
+      newScope? :: AttrSet -> scope,
       directory :: Path,
       recurseIntoDirectory? :: (args -> AttrSet) -> args -> AttrSet,
       ...
@@ -326,6 +327,12 @@ in
     : The function used to convert a Nix file's path into a leaf of the attribute set.
       It is typically the `callPackage` function, taken from either `pkgs` or a new scope corresponding to the `directory`.
 
+    `newScope`
+    : If present, this function is used by the default `recurseIntoDirectory` to generate a new scope.
+      The arguments are updated with the scope's `callPackage` and `newScope` functions, so packages can require
+      anything in their scope, or in an ancestor of their scope.
+      This argument has no effect when `recurseIntoDirectory` is provided.
+
     `directory`
     : The directory to read package files from.
 
@@ -355,12 +362,6 @@ in
     ```nix
     packagesFromDirectoryRecursive {
       inherit (pkgs) callPackage newScope;
-      recurseIntoDirectory = f: { newScope, ... }@args:
-        lib.recurseIntoAttrset (lib.makeScope newScope (self:
-          f (args // {
-            inherit (self) callPackage newScope;
-          })
-        ));
       directory = ./my-packages;
     }
     => { ... }
@@ -387,7 +388,19 @@ in
     {
       callPackage,
       directory,
-      recurseIntoDirectory ? lib.id,
+      recurseIntoDirectory ?
+        # recurseIntoDirectory can modify the function used when processing directory entries; see nixdoc above
+        if args ? newScope then
+          # when `newScope` is provided, create a new scope when recursing into a directory (incl. the top one)
+          processDir: { newScope, ... }@args:
+            lib.recurseIntoAttrs (lib.makeScope newScope (self:
+              processDir (args // {
+                inherit (self) callPackage newScope;
+              })
+            ))
+        else
+          # otherwise, no modification is necessary
+          lib.id,
       ...
     }@args:
     let

diff --git a/lib/tests/misc.nix b/lib/tests/misc.nix
@@ -2529,12 +2529,6 @@ runTests {
   in {
     expr = lib.filterAttrsRecursive (name: value: !lib.elem name [ "callPackage" "newScope" "overrideScope" "packages" ]) (packagesFromDirectoryRecursive {
       inherit (emptyScope) callPackage newScope;
-      recurseIntoDirectory = f: { newScope, ... }@args:
-        recurseIntoAttrs (makeScope newScope (self:
-          f (args // {
-            inherit (self) callPackage newScope;
-          })
-        ));
       directory = ./packages-from-directory/scope;
     });
     expected = lib.recurseIntoAttrs {