Test for Trac #4135, comment 2

testsuite/tests/th/T4135a.hs

+{-# LANGUAGE TemplateHaskell, MultiParamTypeClasses, TypeFamilies,
+             FlexibleInstances, OverlappingInstances #-}
+
+module T4135a where
+
+import Control.Monad
+import Language.Haskell.TH
+
+class Foo a where
+    type FooType a
+
+createInstance' :: Q Type -> Q Dec
+createInstance' t = liftM head [d|
+    instance Foo $t where
+      type FooType $t = String |]

testsuite/tests/th/all.T

@@ -235,7 +235,8 @@ test('T5883', normal, compile, ['-v0 -dsuppress-uniques -ddump-splices'])
 test('T5882', normal, compile, ['-v0'])
 test('T5886', extra_clean(['T5886a.hi','T5886a.o']),
               multimod_compile, ['T5886','-v0 ' + config.ghc_th_way_flags])
-test('T4135', normal, compile, ['-v0'])
+test('T4135',  normal, compile, ['-v0'])
+test('T4135a', normal, compile, ['-v0'])
 test('T5971', normal, compile_fail, ['-v0 -dsuppress-uniques'])
 test('T5968', normal, compile, ['-v0'])
 test('T5984', extra_clean(['T5984_Lib.hi', 'T5984_Lib.o']),