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Using map with two lists rather than one. Can you nest?
runParseTest :: String -> String -> IO()

-- Get list of files in libraries directory
files <- getDirectoryContents "tests/libraries"
-- Filter out ".." and "." and add path
let names = filter (x -> head x /= '.') files
let libs = ["tests/libraries/" ++ f | f <- names]

runParseTest "test1.js" "tests/libraries/test1.js"
runParseTest "test2.js" "tests/libraries/test2.js"
runParseTest "test3.js" "tests/libraries/test3.js"

mapM_ (runParseTest "test") libs

map ((a,b) -> runParseTest a b) $ zip names libs

map (uncurry runParseTest) $ zip names libs

zipWith runParseTest names libs

> :t zipWithM
zipWithM :: Monad m => (a -> b -> m c) -> [a] -> [b] -> m [c]
> :t zipWithM_
zipWithM_ :: Monad m => (a -> b -> m c) -> [a] -> [b] -> m ()

import Data.List (isPrefixOf)

...

-- I got rid of `head` because it's a partial function, and I prefer `map` to
-- list comprehensions for simple things
do files <- getDirectoryContents "tests/libraries"
   let names = filter (not . ("." `isPrefixOf`)) files
       libs  = map ("tests/libraries/" ++) names
   zipWithM_ runParseTest names libs

map2 :: (a -> b -> c) -> [a] -> [b] -> [c]
map2 _ [] _          = []
map2 _ _ []          = []
map2 f (a:as) (b:bs) = f a b : map2 f as bs

map2M_ :: Monad m => (a -> b -> m c) -> [a] -> [b] -> m ()
map2M_ f as bs =  sequence_ (map2 f as bs)