Reduce show skipped versions from 3 to 1

And fix associated unit test expected string.

Author: erikd

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

@@ -291,8 +291,8 @@ showOptions verb q xs = showQPN q ++ "; " ++ (L.intercalate ", "
   [if isJust linkedTo
     then showOption q x
     else showI i -- Don't show the package, just the version
-  | x@(POption i linkedTo) <- if verb >= verbose then xs else take 3 xs
-  ] ++ if verb < verbose && length xs >= 3 then " and other versions" else "")
+  | x@(POption i linkedTo) <- if verb >= verbose then xs else take 1 xs
+  ] ++ if verb < verbose && length xs >= 1 then " and other versions" else "")
 
 showGR :: QGoalReason -> String
 showGR UserGoal            = " (user goal)"

cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs

@@ -971,12 +971,10 @@ tests =
                     [ Right $ exAv "A" 1 []
                     , Right $ exAv "A" 2 []
                     , Right $ exAv "A" 3 []
-                    , Right $ exAv "A" 4 []
-                    , Right $ exAv "A" 5 []
-                    , Right $ exAv "B" 1 [ExFix "A" 6]
+                    , Right $ exAv "B" 1 [ExFix "A" 4]
                     ]
-                  rejecting = "rejecting: A-5.0.0 (conflict: B => A==6.0.0)"
-                  skipping = "skipping: A; 4.0.0, 3.0.0, 2.0.0 and other versions (has"
+                  rejecting = "rejecting: A-3.0.0 (conflict: B => A==4.0.0)"
+                  skipping = "skipping: A; 2.0.0 and other versions (has"
                in mkTest db "show summarized skipping versions list" ["B"] $
                     solverFailure (\msg -> rejecting `isInfixOf` msg && skipping `isInfixOf` msg)
           ]