Fix bild --repl to use the proper hasakell package set

1 files changed, 13 insertions, 8 deletions

diff --git a/Biz/Bild.hs b/Biz/Bild.hs
index 4d7fadd..845daf1 100644
--- a/Biz/Bild.hs
+++ b/Biz/Bild.hs
@@ -469,18 +469,23 @@ test loud Target {..} = case compiler of
       >> pure Exit.ExitSuccess
 
 repl :: Bool -> Target -> IO Exit.ExitCode
-repl _ Target {..} =
+repl _ Target {..} = do
+  root <- Env.getEnv "BIZ_ROOT"
   case compiler of
     c
       | c `elem` [GhcExe, GhcLib] ->
-        [ ["--packages"],
-          ["haskellPackages." <> d | d <- Set.toList langdeps],
-          Set.toList sysdeps,
-          [ "--command",
-            "ghci -i$BIZ_ROOT -ghci-script $BIZ_ROOT/.ghci " <> path
-          ]
+        -- this is a complicated set of string joins which basically means to
+        -- create a command like this:
+        --   nix-shell -E "with import Biz/Bild.nix {}; mkGhcPackageSet (h: [h.pkg])"
+        [ "--expr",
+          "with import " <> root <> "/Biz/Bild.nix {};"
+            <> "mkGhcPackageSet (h: ["
+            <> joinWith " " ["h." <> d | d <- Set.toList langdeps]
+            <> "])",
+          -- Set.toList sysdeps,
+          "--command",
+          "ghci -i$BIZ_ROOT -ghci-script $BIZ_ROOT/.ghci " <> path
         ]
-          |> mconcat
           |> Process.callProcess "nix-shell"
           >> Exit.exitSuccess
     _ ->