Implement cabal v2 backpack unit workaround

See https://github.com/haskell/cabal/issues/6201 for details about the bug

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/Distribution/Helper.hs b/lib/Distribution/Helper.hs
index 55bfbf7..e46293d 100644
--- a/lib/Distribution/Helper.hs
+++ b/lib/Distribution/Helper.hs
@@ -508,7 +508,11 @@ buildProjectTarget qe mu stage = do
           SCV2 -> do
             targets <- return $ case mu of
               Nothing -> ["all"]
-              Just Unit{uImpl} -> uiV2Components uImpl
+              Just Unit{uImpl} -> concat
+                [ if uiV2OnlyDependencies uImpl
+                    then ["--only-dependencies"] else []
+                , uiV2Components uImpl
+                ]
             case qeProjLoc of
               ProjLocV2File {plCabalProjectFile} ->
                 [ "--project-file="++plCabalProjectFile