[ #1675, tests ] Don't run latex compilers on travis.

.travis.yml

@@ -219,8 +219,11 @@ script:
 
 ##############################################################################
 
+# Running XeLaTeX/LuaLaTeX on travis fails randomly, presumably because they
+# consume too much memory. We just don't run them on travis, but we still
+# compare the generated tex/html files with the golden files.
   - if [ $TEST = "latex-html-test" ]; then
-       make AGDA_TESTS_OPTIONS="" BUILD_DIR=$BUILD_DIR latex-html-test;
+       make AGDA_TESTS_OPTIONS="" BUILD_DIR=$BUILD_DIR DONT_RUN_LATEX="Y" latex-html-test;
     fi
 
 ##############################################################################

test/LaTeXAndHTML/Tests.hs

@@ -99,7 +99,11 @@ mkLaTeXOrHTMLTest k agdaBin inp = do
                     fromMaybe allLaTeXProgs
                       (readMaybe $ T.unpack $ decodeUtf8 content)
               -- run all latex compilers
-              foldl (runLaTeX outFileName outDir) done latexProgs
+              rl <- doesEnvContain "DONT_RUN_LATEX"
+              if rl
+                then done
+                else
+                  foldl (runLaTeX outFileName outDir) done latexProgs
 
   runLaTeX :: FilePath -- tex file
       -> FilePath -- working dir

test/Main.hs

@@ -18,16 +18,18 @@ import Test.Tasty.Silver.Filter (RegexFilter)
 import Control.Applicative ((<$>))
 #endif
 
-import System.Environment
 import System.Exit
 
+import Utils
+
 main :: IO ()
 main = do
-  env <- getEnvironment
-  case "AGDA_BIN" `lookup` env of
-    Just _ -> tests >>= TM.defaultMain1 disabledTests
-    Nothing -> do
-        putStrLn $ unlines
+  agdaBin <- doesEnvContain "AGDA_BIN"
+  if agdaBin
+    then
+      tests >>= TM.defaultMain1 disabledTests
+    else do
+      putStrLn $ unlines
             [ "The AGDA_BIN environment variable is not set. Do not execute"
             , "these tests directly using \"cabal test\" or \"cabal install --run-tests\", instead"
             , "use the Makefile."
@@ -36,7 +38,7 @@ main = do
             , "The Makefile requries cabal-install 1.20.0.0 or later to work properly."
             , "See also Issue 1489 and 1490."
             ]
-        exitWith (ExitFailure 1)
+      exitWith (ExitFailure 1)
 
 tests :: IO TestTree
 tests =

test/Utils.hs

@@ -51,6 +51,8 @@ agdaExts = S.fromList [".agda", ".lagda"]
 getAgdaFilesInDir :: String -> IO [FilePath]
 getAgdaFilesInDir dir = map (dir </>) . filter (flip S.member agdaExts . takeExtension) <$> getDirectoryContents dir
 
+doesEnvContain :: String -> IO Bool
+doesEnvContain v = isJust <$> getEnvVar v
 
 -- | Replaces all matches of a regex with the given text.
 --