[commit: stm] master: Add a test for orElse bug (713c94c)

[Simon Marlow]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/stm

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/713c94cdf3127c96a4e1d377b4008b48b3b934ed

>---------------------------------------------------------------

commit 713c94cdf3127c96a4e1d377b4008b48b3b934ed
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Mon Dec 10 12:18:33 2012 +0000

    Add a test for orElse bug
    
    Fixed in GHC commit f184d9caffa09750ef6a374a7987b9213d6db28e, see that
    for more details.

>---------------------------------------------------------------

 tests/stm064.hs     |    8 ++++++++
 tests/stm064.stdout |    1 +
 2 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/tests/stm064.hs b/tests/stm064.hs
new file mode 100644
index 0000000..a8ff170
--- /dev/null
+++ b/tests/stm064.hs
@@ -0,0 +1,8 @@
+import Control.Concurrent.STM
+main = do
+  x <- atomically $ do
+         t <- newTVar 1
+         writeTVar t 2
+         ((readTVar t >> retry) `orElse` return ()) `orElse` return ()
+         readTVar t
+  print x
diff --git a/tests/stm064.stdout b/tests/stm064.stdout
new file mode 100644
index 0000000..0cfbf08
--- /dev/null
+++ b/tests/stm064.stdout
@@ -0,0 +1 @@
+2