feat(by-name-overlay.nix): Support non-sharded by-name directories prime

1 files changed, 28 insertions, 19 deletions

diff --git a/by-name-overlay.nix b/by-name-overlay.nix
index 4d700a8..80aebf4 100644
--- a/by-name-overlay.nix
+++ b/by-name-overlay.nix
@@ -7,6 +7,7 @@
   finalizeFunction,
   coImportsNameFunction ? null,
   coImportsWarnMessageObject ? null,
+  useShards ? true,
 }: let
   # Takes a list of attrs as input and returns one merged attr set.
   flattenAttrs = list:
@@ -43,27 +44,35 @@
   namesForShard = shard: type:
     if type != "directory"
     then warn "Ignored non-directory, whilst importing by-name directory (${fileName}): '${shard}'" {}
-    else let
-      mkPath = name: _type: let
-        path = baseDirectory + "/${shard}/${name}" + "/${fileName}";
-        coImportPath =
-          if coImportsNameFunction != null
-          then
-            coImportsNameFunction
-            {inherit shard name;}
-          else path;
-      in
-        if builtins.pathExists path
+    else if useShards
+    then namesForElement shard type
+    else namesForElement "." type;
+
+  namesForElement = shard: _type: let
+    mkPath = name: type: let
+      path = baseDirectory + "/${shard}/${name}" + "/${fileName}";
+      coImportPath =
+        if coImportsNameFunction != null
         then
-          if builtins.pathExists coImportPath
-          then path
-          else warn "'${builtins.toString coImportPath}' does not exist. Should include ${coImportsWarnMessageObject} for '${shard}/${name}'" path
-        else warn "'${builtins.toString path}' does not exist. Skipped" null;
+          coImportsNameFunction
+          {inherit shard name;}
+        else path;
     in
-      filterAttrs (name: value: value != null)
-      (builtins.mapAttrs
-        mkPath
-        (builtins.readDir (baseDirectory + "/${shard}")));
+      if builtins.pathExists path
+      then
+        if type != "directory"
+        then
+          # The `namesForShard` function should have already printed a warning.
+          null
+        else if builtins.pathExists coImportPath
+        then path
+        else warn "'${builtins.toString coImportPath}' does not exist. Should include ${coImportsWarnMessageObject} for '${shard}/${name}'" path
+      else warn "'${builtins.toString path}' does not exist. Skipped" null;
+  in
+    filterAttrs (name: value: value != null)
+    (builtins.mapAttrs
+      mkPath
+      (builtins.readDir (baseDirectory + "/${shard}")));
 
   # A list of all module paths.
   # These can the be simply injected into `import`