From 0007a5adc2460ec3bca4b86eda670a93bf91c3c3 Mon Sep 17 00:00:00 2001
From: Simon Hengel <sol@typeful.net>
Date: Mon, 15 Oct 2012 20:03:43 +0200
Subject: Add test case for "spurious superclass constraints bug"

---
 html-test/tests/SpuriousSuperclassConstraints.hs | 30 ++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 html-test/tests/SpuriousSuperclassConstraints.hs

(limited to 'html-test/tests')

diff --git a/html-test/tests/SpuriousSuperclassConstraints.hs b/html-test/tests/SpuriousSuperclassConstraints.hs
new file mode 100644
index 00000000..d9e43e1c
--- /dev/null
+++ b/html-test/tests/SpuriousSuperclassConstraints.hs
@@ -0,0 +1,30 @@
+{-# LANGUAGE EmptyDataDecls, KindSignatures #-}
+-- |
+-- What is tested here:
+--
+-- Due to a change in GHC 7.6.1 we had a bug that superclass contraints were
+-- included in the instances list.  Edward K. repported it here:
+--
+--   <http://www.haskell.org/pipermail/haskell-cafe/2012-September/103600.html>
+--
+-- And here is the corresponding theard on glasgow-haskell-users:
+--
+--   <http://www.haskell.org/pipermail/glasgow-haskell-users/2012-September/022914.html>
+--
+-- It has been fixed in:
+--
+-- > 6ccf78e15a525282fef61bc4f58a279aa9c21771
+-- > Fix spurious superclass constraints bug.
+--
+module SpuriousSuperclassConstraints where
+
+import Control.Applicative
+
+data SomeType (f :: * -> *) a
+
+instance Functor (SomeType f) where
+  fmap = undefined
+
+instance Applicative f => Applicative (SomeType f) where
+  pure   = undefined
+  (<*>)  = undefined
-- 
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