npins: restore asFlake patch

npins/default.nix

@@ -112,7 +112,18 @@ let
         else
           builtins.throw "Unknown source type ${spec.type}";
     in
-    spec // { outPath = mayOverride name path; };
+    spec
+    // rec {
+      outPath = mayOverride name path;
+
+      # Waiting for discussion upstream
+      # https://github.com/andir/npins/issues/159
+      asFlake =
+        if sources ? flake-compat then
+          (import sources.flake-compat { src = outPath; }).outputs
+        else
+          throw ".asFlake needs flake-compat as a source";
+    };
 
   mkGitSource =
     {
@@ -221,8 +232,8 @@ let
         imageDigest = image_digest;
         finalImageTag = image_tag;
       };
-in
-mkFunctor (
+
+  sources = mkFunctor (
     {
       input ? ./sources.json,
     }:
@@ -246,4 +257,6 @@ mkFunctor (
       builtins.mapAttrs (name: spec: mkFunctor (mkSource name spec)) data.pins
     else
       throw "Unsupported format version ${toString version} in sources.json. Try running `npins upgrade`"
-)
+  );
+in
+sources