Copy tests from GHC testsuite; part of #1161.

1 files changed, 33 insertions, 0 deletions

diff --git a/libraries/base/tests/hTell002.hs b/libraries/base/tests/hTell002.hs
new file mode 100644
index 0000000000..b790db8fe8
--- /dev/null
+++ b/libraries/base/tests/hTell002.hs
@@ -0,0 +1,33 @@
+-- !!! Testing hSeek
+module Main(main) where
+
+import System.Directory
+import System.IO
+
+main :: IO ()
+main = do
+  h <- openFile "tst-seek" WriteMode
+  hSetEncoding h utf8 -- hSeek/hTell work with Unicode streams
+  hPutStr h "test string1"
+   -- seek to EOF should be cool..
+  hSeek h SeekFromEnd 0
+  hPutStr h "test string2"
+   -- seek past EOF should now also be cool..
+  hSeek h SeekFromEnd 3
+  hPutStr h "test string3"
+  hSeek h AbsoluteSeek 13
+  hPutStr h "test string4"
+  x <- hTell h
+  print x
+  hSeek h AbsoluteSeek 30
+  x1 <- hTell h
+  hPutStr h "人間虫" -- we should be able to output Unicode too
+  x2 <- hTell h
+  print (x2 - x1)
+  hPutStr h "filler"
+  hClose h
+  h <- openFile "tst-seek" ReadMode
+  hSetEncoding h utf8
+  str <- hGetContents h
+  putStrLn str
+  removeFile "tst-seek"