Add build-info location to plan.json

Author: fendor

cabal-install/src/Distribution/Client/ProjectPlanOutput.hs

@@ -45,7 +45,7 @@ import           Distribution.Simple.GHC
                    , GhcEnvironmentFileEntry(..), simpleGhcEnvironmentFile
                    , writeGhcEnvironmentFile )
 import           Distribution.Simple.BuildPaths
-                   ( dllExtension, exeExtension )
+                   ( dllExtension, exeExtension, buildInfoPref )
 import qualified Distribution.Compat.Graph as Graph
 import           Distribution.Compat.Graph (Graph, Node)
 import qualified Distribution.Compat.Binary as Binary
@@ -150,7 +150,9 @@ encodePlanAsJson distDirLayout elaboratedInstallPlan elaboratedSharedConfig =
         | Just hash <- [elabPkgSourceHash elab] ] ++
         (case elabBuildStyle elab of
             BuildInplaceOnly ->
-                ["dist-dir"   J..= J.String dist_dir]
+                [ "dist-dir"   J..= J.String dist_dir
+                , "build-info" J..= J.String (buildInfoPref dist_dir)
+                ]
             BuildAndInstall ->
                 -- TODO: install dirs?
                 []