Move tests from tests/ghc-regress/* to just tests/*

1 files changed, 23 insertions, 0 deletions

diff --git a/testsuite/tests/typecheck/should_compile/tc179.hs b/testsuite/tests/typecheck/should_compile/tc179.hs
new file mode 100644
index 0000000000..110950587d
--- /dev/null
+++ b/testsuite/tests/typecheck/should_compile/tc179.hs
@@ -0,0 +1,23 @@
+{-# LANGUAGE ExistentialQuantification, FlexibleInstances,
+             OverlappingInstances, UndecidableInstances #-}
+
+-- Tests context reduction for existentials
+
+module TestWrappedNode where
+
+class Foo a where { op :: a -> Int }
+
+instance Foo a => Foo [a] where  	-- NB overlap
+  op (x:xs) = op x
+instance Foo [Int] where		-- NB overlap
+  op x = 1
+
+data T = forall a. Foo a => MkT a
+
+f :: T -> Int
+f (MkT x) = op [x,x]
+	-- The op [x,x] means we need (Foo [a]).  We used to 
+	-- complain, saying that the choice of instance depended on 
+	-- the instantiation of 'a'; but of course it isn't *going* 
+	-- to be instantiated.
+