Revert the change to filter out deps of non-buildable components

It does not work as intended and gives inconsistent results between
cabal install and cabal configure. The problem with the approach was
that we were filtering out the dependencies of non-buildable components
at the end. But that does not help much since if one of the deps of
the non-buildable component were not available then we would have
failed earlier with a constraint failure. A proper solution would have
to tackle it from the beginning, not just as a filter at the end.
The meaning of build-depends and buildable: False needs more thought.

Author: dcoutts

Distribution/PackageDescription/Configuration.hs

@@ -65,9 +65,7 @@ import Distribution.PackageDescription
          , Flag(..), FlagName(..), FlagAssignment
          , CondTree(..), ConfVar(..), Condition(..) )
 import Distribution.Version
-         ( VersionRange, anyVersion, intersectVersionRanges, withinRange
-         , toVersionIntervals, intersectVersionIntervals
-         , fromVersionIntervals )
+         ( VersionRange, anyVersion, intersectVersionRanges, withinRange )
 import Distribution.Compiler
          ( CompilerId(CompilerId) )
 import Distribution.System
@@ -81,7 +79,6 @@ import Distribution.Compat.ReadP as ReadP hiding ( char )
 import Control.Arrow (first)
 import qualified Distribution.Compat.ReadP as ReadP ( char )
 
-import Control.Exception (assert)
 import Data.Char ( isAlphaNum )
 import Data.Maybe ( catMaybes, maybeToList )
 import Data.Map ( Map, fromListWith, toList )
@@ -489,29 +486,13 @@ finalizePackageDescription userflags satisfyDep (Platform arch os) impl constrai
       Right ((mlib, exes'), targetSet, flagVals) ->
         Right ( pkg { library = mlib
                     , executables = exes'
-                    , buildDepends = assert sanity overallDeps
+                    , buildDepends = fromDepMap (overallDependencies targetSet)
+                      --TODO: we need to find a way to avoid pulling in deps
+                      -- for non-buildable components. However cannot simply
+                      -- filter at this stage, since if the package were not
+                      -- available we would have failed already.
                     }
               , flagVals )
-        where
-          -- Note that we exclude non-buildable components. This means your tools and
-          -- test progs to not contribute to the overall package dependencies.
-          --
-          overallDeps = canonicalise
-                      . concatMap targetBuildDepends
-                      . filter buildable
-                      $ buildInfos
-          buildInfos  = map libBuildInfo (maybeToList mlib) ++ map buildInfo exes'
-
-          -- as a sanity check, check that the overall deps from the target set
-          -- matches those from the (unfiltered for being buildable) components
-          sanity        = canonicalise overallDeps' == canonicalise overallDeps''
-          overallDeps'  = concatMap targetBuildDepends buildInfos
-          overallDeps'' = fromDepMap (overallDependencies targetSet)
-          canonicalise  =
-              map (\(name, vi) -> Dependency name (fromVersionIntervals vi))
-            . Map.toList
-            . Map.fromListWith intersectVersionIntervals
-            . map (\(Dependency name vr) -> (name, toVersionIntervals vr))
 
       Left missing -> Left missing
   where