defer build-tools-depends choices as well as setup choices (backport #7532) (#7538)

* defer build-tools-depends choices as well as setup choices

(cherry picked from commit 3ac512e)

* Update Preference.hs

* Update Solver.hs

Co-authored-by: Gershom Bazerman <[email protected]>
Co-authored-by: gbaz <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: mergify[bot]

cabal-install/cabal-install-solver/src/Distribution/Solver/Modular/Preference.hs

@@ -2,7 +2,7 @@
 -- | Reordering or pruning the tree in order to prefer or make certain choices.
 module Distribution.Solver.Modular.Preference
     ( avoidReinstalls
-    , deferSetupChoices
+    , deferSetupExeChoices
     , deferWeakFlagChoices
     , enforceManualFlags
     , enforcePackageConstraints
@@ -400,17 +400,18 @@ preferBaseGoalChoice = trav go
     isBase (Goal (P (Q _pp pn)) _) = unPN pn == "base"
     isBase _                       = False
 
--- | Deal with setup dependencies after regular dependencies, so that we can
--- will link setup dependencies against package dependencies when possible
-deferSetupChoices :: Tree d c -> Tree d c
-deferSetupChoices = trav go
+-- | Deal with setup and build-tool-depends dependencies after regular dependencies,
+-- so we will link setup/exe dependencies against package dependencies when possible
+deferSetupExeChoices :: Tree d c -> Tree d c
+deferSetupExeChoices = trav go
   where
-    go (GoalChoiceF rdm xs) = GoalChoiceF rdm (P.preferByKeys noSetup xs)
+    go (GoalChoiceF rdm xs) = GoalChoiceF rdm (P.preferByKeys noSetupOrExe xs)
     go x                    = x
 
-    noSetup :: Goal QPN -> Bool
-    noSetup (Goal (P (Q (PackagePath _ns (QualSetup _)) _)) _) = False
-    noSetup _                                                  = True
+    noSetupOrExe :: Goal QPN -> Bool
+    noSetupOrExe (Goal (P (Q (PackagePath _ns (QualSetup _)) _)) _) = False
+    noSetupOrExe (Goal (P (Q (PackagePath _ns (QualExe _ _)) _)) _) = False
+    noSetupOrExe _                                                  = True
 
 -- | Transformation that tries to avoid making weak flag choices early.
 -- Weak flags are trivial flags (not influencing dependencies) or such

cabal-install/cabal-install-solver/src/Distribution/Solver/Modular/Solver.hs

@@ -117,7 +117,7 @@ solve sc cinfo idx pkgConfigDB userPrefs userConstraints userGoals =
           sortGoals = case goalOrder sc of
                         Nothing -> goalChoiceHeuristics .
                                    heuristicsTree .
-                                   P.deferSetupChoices .
+                                   P.deferSetupExeChoices .
                                    P.deferWeakFlagChoices .
                                    P.preferBaseGoalChoice
                         Just order -> P.firstGoal .