Changed RunTests.hs to use the Diff library.

Previously a copy of Diff.hs was included.  But it is better
to use the compiled, installed version, since speed can be
a problem in some cases.

This change means that 'cabal test' presupposes that the Diff
library is installed.

Removed tests/Diff.hs from cabal file.

Changed RunTests to use local environment.
We need at least HOME, so pandoc can find its data directory.

git-svn-id: https://pandoc.googlecode.com/svn/trunk@1672 788f1e2b-df1e-0410-8736-df70ead52e1b

3 files changed, 10 insertions, 81 deletions

diff --git a/pandoc.cabal b/pandoc.cabal
index d441e6f55..cd5e6bbe0 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -126,7 +126,6 @@ Extra-Source-Files:
                  tests/lhs-test.html,
                  tests/lhs-test.html+lhs,
                  tests/lhs-test.fragment.html+lhs,
-                 tests/Diff.hs,
                  tests/RunTests.hs
 Extra-Tmp-Files: man/man1/pandoc.1, man/man1/hsmarkdown.1,
                  man/man1/html2markdown.1, man/man1/markdown2pdf.1
diff --git a/tests/Diff.hs b/tests/Diff.hs
deleted file mode 100644
index f7e562ee2..000000000
--- a/tests/Diff.hs
+++ /dev/null
@@ -1,76 +0,0 @@
------------------------------------------------------------------------------
--- |
--- Module      :  Data.Algorithm.Diff
--- Copyright   :  (c) Sterling Clover 2008
--- License     :  BSD 3 Clause
--- Maintainer  :  s.clover@gmail.com
--- Stability   :  experimental
--- Portability :  portable
---
--- This is an implementation of the O(ND) diff algorithm as described in
--- \"An O(ND) Difference Algorithm and Its Variations (1986)\"
--- <http://citeseer.ist.psu.edu/myers86ond.html>. It is O(mn) in space.
--- The algorithm is the same one used by standared Unix diff.
--- The assumption is that users of this library will want to diff over
--- interesting things or peform interesting tasks with the results
--- (given that, otherwise, they would simply use the standard Unix diff
--- utility). Thus no attempt is made to present a fancier API to aid
--- in doing standard and uninteresting things with the results.
------------------------------------------------------------------------------
-
-module Diff (DI(..), getDiff, getGroupedDiff) where
-import Data.Array
-import Data.List
-
--- | Difference Indicator. A value is either from the First list, the Second
--- or from Both.
-data DI = F | S | B deriving (Show, Eq)
-
-data DL = DL {poi::Int, poj::Int, path::[DI]} deriving (Show, Eq)
-
-instance Ord DL where x <= y = poi x <= poi y
-
-canDiag :: (Eq a)  => [a] -> [a] -> Int -> Int -> (Int, Int) -> Bool
-canDiag as bs lena lenb = \(i,j) ->
-   if i < lena && j < lenb then arAs ! i == arBs ! j else False
-    where arAs = listArray (0,lena - 1) as
-          arBs = listArray (0,lenb - 1) bs
-
-chunk :: Int -> [a] -> [[a]]
-chunk x = unfoldr (\a -> case splitAt x a of ([],[]) -> Nothing; a' -> Just a')
-
-dstep :: ((Int,Int)->Bool) -> [DL] -> [DL]
-dstep cd dls = map maximum $ [hd]:(chunk 2 rst)
-    where (hd:rst)  = concatMap extend dls
-          extend dl = let pdl = path dl
-                      in [addsnake cd $ dl {poi=poi dl + 1, path=(F : pdl)},
-                          addsnake cd $ dl {poj=poj dl + 1, path=(S : pdl)}]
-
-addsnake :: ((Int,Int)->Bool) -> DL -> DL
-addsnake cd dl
-    | cd (pi, pj) = addsnake cd $
-                   dl {poi = pi + 1, poj = pj + 1, path=(B : path dl)}
-    | otherwise   = dl
-    where pi = poi dl; pj = poj dl
-
-lcs :: (Eq a) => [a] -> [a] -> [DI]
-lcs as bs = path . head . dropWhile (\dl -> poi dl /= lena || poj dl /= lenb) .
-            concat . iterate (dstep cd) . (:[]) . addsnake cd $
-            DL {poi=0,poj=0,path=[]}
-            where cd = canDiag as bs lena lenb
-                  lena = length as; lenb = length bs
-
--- | Takes two lists and returns a list indicating the differences
--- between them.
-getDiff :: (Eq t) => [t] -> [t] -> [(DI, t)]
-getDiff a b = markup a b . reverse $ lcs a b
-    where markup (x:xs)   ys   (F:ds) = (F, x) : markup xs ys ds
-          markup   xs   (y:ys) (S:ds) = (S, y) : markup xs ys ds
-          markup (x:xs) (_:ys) (B:ds) = (B, x) : markup xs ys ds
-          markup _ _ _ = []
-
--- | Takes two lists and returns a list indicating the differences
--- between them, grouped into chunks.
-getGroupedDiff :: (Eq t) => [t] -> [t] -> [(DI, [t])]
-getGroupedDiff a b = map go . groupBy (\x y -> fst x == fst y) $ getDiff a b
-    where go ((d,x) : xs) = (d, x : map snd xs)
diff --git a/tests/RunTests.hs b/tests/RunTests.hs
index 90e2276b2..f6c39b5bc 100644
--- a/tests/RunTests.hs
+++ b/tests/RunTests.hs
@@ -8,11 +8,14 @@
 -- If the lhs argument is provided, tests for lhs support will be
 -- run.  These presuppose that pandoc has been compiled with the
 -- -fhighlighting flag, so these tests are not run by default.
+--
+-- This program assumes that the Diff package has been installed:
+-- cabal install Diff
 
 module Main where
 import System.Exit
 import System.IO.UTF8
-import System.IO ( openTempFile, stderr )
+import System.IO ( openTempFile, stderr, stdout, hFlush )
 import Prelude hiding ( putStrLn, putStr, readFile )
 import System.Process ( runProcess, waitForProcess )
 import System.FilePath ( (</>), (<.>) )
@@ -20,7 +23,7 @@ import System.Directory
 import System.Environment
 import System.Exit
 import Text.Printf
-import Diff
+import Data.Algorithm.Diff
 
 pandocPath :: FilePath
 pandocPath = ".." </> "dist" </> "build" </> "pandoc" </> "pandoc"
@@ -143,11 +146,14 @@ runTest  :: String                      -- ^ Title of test
          -> FilePath                    -- ^ Norm (for test results) filepath
          -> IO Bool
 runTest testname opts inp norm = do
+  putStr $ printf "%-28s ---> " testname
   (outputPath, hOut) <- openTempFile "" "pandoc-test"
   let inpPath = inp
   let normPath = norm
+  hFlush stdout
+  env <- getEnvironment  -- we need at least HOME so pandoc can find data files
   -- Note: COLUMNS must be set for markdown table reader
-  ph <- runProcess pandocPath (opts ++ [inpPath]) Nothing (Just [("COLUMNS", "80")]) Nothing (Just hOut) (Just stderr)
+  ph <- runProcess pandocPath (opts ++ [inpPath]) Nothing (Just (("COLUMNS", "80"):env)) Nothing (Just hOut) (Just stderr)
   ec <- waitForProcess ph
   result  <- if ec == ExitSuccess
                 then do
@@ -159,5 +165,5 @@ runTest testname opts inp norm = do
                      else return $ TestFailed $ getDiff (lines outputContents) (lines normContents)
                 else return $ TestError ec
   removeFile outputPath
-  putStrLn $ printf "%-28s ---> %s" testname (show result)
+  putStrLn (show result)
   return (result == TestPassed)