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authorVincent Ambo <mail@tazj.in>2021-12-13T22·51+0300
committerVincent Ambo <mail@tazj.in>2021-12-13T23·15+0300
commit019f8fd2113df4c5247c3969c60fd4f0e08f91f7 (patch)
tree76a857f61aa88f62a30e854651e8439db77fd0ea /users/wpcarro/haskell-file/f.hs
parent464bbcb15c09813172c79820bcf526bb10cf4208 (diff)
parent6123e976928ca3d8d93f0b2006b10b5f659eb74d (diff)
subtree(users/wpcarro): docking briefcase at '24f5a642' r/3226
git-subtree-dir: users/wpcarro
git-subtree-mainline: 464bbcb15c09813172c79820bcf526bb10cf4208
git-subtree-split: 24f5a642af3aa1627bbff977f0a101907a02c69f
Change-Id: I6105b3762b79126b3488359c95978cadb3efa789
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+module F
+  ( join
+  , split
+  ) where
+
+--------------------------------------------------------------------------------
+-- Dependencies
+--------------------------------------------------------------------------------
+
+import Data.List (span)
+import System.FilePath (FilePath, pathSeparator)
+import System.FilePath.Posix (FilePath)
+import qualified System.FilePath.Posix as F
+
+-- TODO: Move this to a misc.hs, prelude.hs, operators.hs; somewhere.
+(|>) :: a -> (a -> b) -> b
+(|>) a f = f a
+infixl 1 |>
+
+-- TODO: Move this to a test_utils.hs or elsewhere.
+simpleAssert :: (Eq a) => a -> a -> ()
+simpleAssert x y =
+  if x == y then
+    ()
+  else
+    error "Assertion error"
+
+--------------------------------------------------------------------------------
+-- Library
+--------------------------------------------------------------------------------
+
+join :: [FilePath] -> FilePath
+join = F.joinPath
+
+-- | Split path and return  list containing parts.
+split :: FilePath -> [String]
+split = splitJoin . span (/= pathSeparator)
+  where
+    splitJoin :: (String, String) -> [String]
+    splitJoin ([], []) = []
+    splitJoin (a, []) = [a]
+    splitJoin (a, [_]) = [a]
+    splitJoin (a, _:b) = a : split b
+
+--------------------------------------------------------------------------------
+-- Tests
+--------------------------------------------------------------------------------
+
+expected :: [([FilePath], FilePath)]
+expected = [ (["path"], "path")
+           , (["/path"], "/path")
+           , (["path", "to", "file"], "path/to/file")
+           , (["/path", "to", "file"], "/path/to/file")
+           , (["/"], "/")
+           ]
+
+runTests :: [()]
+runTests =
+  fmap (\(input, expected) -> simpleAssert (join input) expected) expected
+
+main :: IO ()
+main = do
+  print runTests
+  pure ()