1 files changed, 18 insertions, 0 deletions

diff --git a/libs.nix b/libs.nix
index c85808b..ad517f2 100644
--- a/libs.nix
+++ b/libs.nix
@@ -37,4 +37,22 @@ in
     };
 
   checkEnv = var: builtins.stringLength (builtins.getEnv var) > 0;
+
+  wrap = { paths ? [], vars ? {}, file ? null, script ? null, name ? "wrap" }:
+    assert file != null || script != null ||
+      abort "wrap needs 'file' or 'script' argument";
+    with rec {
+      set  = n: v: "--set ${pkgs.lib.escapeShellArg n} " +
+                    "${pkgs.lib.escapeShellArg v}";
+      args = (map (p: "--prefix PATH : ${p}/bin") paths) ++
+            (builtins.attrValues (pkgs.lib.mapAttrs set vars));
+    };
+    runCommand name
+      {
+        f           = if file == null then writeScript name script else file;
+        buildInputs = [ makeWrapper ];
+      }
+      ''
+        makeWrapper "$f" "$out" ${toString args}
+      '';
 }