From 0eae3c428916c77a69d301825e5c38c49a1f9313 Mon Sep 17 00:00:00 2001
From: Utku Demir <me@utdemir.com>
Date: Mon, 8 Nov 2021 19:27:51 +1300
Subject: [PATCH] fix: Automatically enable nix-command experimental feature on
 Nix>=2.4

---
 CHANGELOG.md             |  1 +
 src/NixTree/StorePath.hs | 12 +++++++-----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1420dff..3c2f08d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+* fix: Automatically enable the required 'nix-command' experimental feature on Nix >= 2.4
 * fix: Do not refresh screen periodically unless necessary
 
 ## 0.1.8 - 2021-09-06:
diff --git a/src/NixTree/StorePath.hs b/src/NixTree/StorePath.hs
index aeb8ceb..e6d5bb8 100644
--- a/src/NixTree/StorePath.hs
+++ b/src/NixTree/StorePath.hs
@@ -106,28 +106,30 @@ mkStorePaths names = do
   -- > the output of given derivation; to actually work on the derivation you need to pass
   -- > --derivation.
   isAtLeastNix24 <- (>= Just "2.4") <$> getNixVersion
+
   let (derivations, outputs) =
         partition
           (\i -> ".drv" `T.isSuffixOf` storeNameToText i)
           (NE.toList names)
   (++)
-    <$> maybe (return []) (getPathInfo nixStore False) (NE.nonEmpty outputs)
-    <*> maybe (return []) (getPathInfo nixStore (True && isAtLeastNix24)) (NE.nonEmpty derivations)
+    <$> maybe (return []) (getPathInfo nixStore isAtLeastNix24 False) (NE.nonEmpty outputs)
+    <*> maybe (return []) (getPathInfo nixStore isAtLeastNix24 True) (NE.nonEmpty derivations)
   where
     getNixVersion :: IO (Maybe Text)
     getNixVersion = do
       out <- decodeUtf8 . BL.toStrict <$> readProcessStdout_ (proc "nix" ["--version"])
       return . viaNonEmpty last $ T.splitOn " " out
 
-getPathInfo :: NixStore -> Bool -> NonEmpty (StoreName s) -> IO [StorePath s (StoreName s) ()]
-getPathInfo nixStore isDrv names = do
+getPathInfo :: NixStore -> Bool -> Bool -> NonEmpty (StoreName s) -> IO [StorePath s (StoreName s) ()]
+getPathInfo nixStore isAtLeastNix24 isDrv names = do
   infos <-
     decode @[NixPathInfoResult]
       <$> readProcessStdout_
         ( proc
             "nix"
             ( ["path-info", "--recursive", "--json"]
-                ++ (if isDrv then ["--derivation"] else [])
+                ++ (if isAtLeastNix24 then ["--extra-experimental-features", "nix-command"] else [])
+                ++ (if isDrv && isAtLeastNix24 then ["--derivation"] else [])
                 ++ map storeNameToPath (toList names)
             )
         )