tests.haskell: set meta.platforms

This allows packagePlatforms to pick up on the overall supported
platforms and schedule builds on Hydra for more than the evaluation
platform (usually x86_64-linux).

pkgs/test/haskell/documentationTarball/default.nix

@@ -4,7 +4,11 @@ let
   drv = haskellPackages.vector;
   docs = pkgs.haskell.lib.documentationTarball drv;
 
-in pkgs.runCommand "test haskell.lib.documentationTarball" { } ''
+in pkgs.runCommand "test haskell.lib.documentationTarball" {
+  meta = {
+    inherit (docs.meta) platforms;
+  };
+} ''
   tar xvzf "${docs}/${drv.name}-docs.tar.gz"
 
   # Check for Haddock html

pkgs/test/haskell/setBuildTarget/default.nix

@@ -30,7 +30,12 @@ let
          fi
      '';
 
-in pkgs.runCommand "test haskell.lib.setBuildTarget" {} ''
+in
+pkgs.runCommand "test haskell.lib.setBuildTarget" {
+  meta = {
+    inherit (drv.meta) platforms;
+  };
+} ''
   ${test "foo" "bar"}
   ${test "bar" "foo"}
   touch "$out"

pkgs/test/haskell/shellFor/default.nix

@@ -29,5 +29,8 @@
       additionalMaintainers = with lib.maintainers; [ cdepillabout ];
       allMaintainers = oldMaintainers ++ additionalMaintainers;
     in
-    oldMeta // { maintainers = allMaintainers; };
+    oldMeta // {
+      maintainers = allMaintainers;
+      inherit (cabal-install.meta) platforms;
+    };
 })

pkgs/test/haskell/writers/default.nix

@@ -14,7 +14,11 @@ let
     ;
 in
 
-runCommand "test-haskell-writers" {} ''
+runCommand "test-haskell-writers" {
+  meta = {
+    inherit (tests.writers.meta) platforms;
+  };
+} ''
   ${writeTest "success" "test-haskell-bin-writer" "${bin.haskell}/bin/${bin.haskell.name}"}
   ${writeTest "success" "test-haskell-simple-writer" simple.haskell}
   ${writeTest "success" "test-haskell-path-writer" path.haskell}