Add path comparison operations

core/src/Streamly/Internal/FileSystem/Path/Common.hs

@@ -43,6 +43,10 @@ module Streamly.Internal.FileSystem.Path.Common
     , unsafeJoinPaths
  -- , processParentRefs
 
+    , eqPathBytes
+    , eqPathStrict
+    , eqPathLax
+
     -- * Utilities
     , wordToChar
     , charToWord
@@ -819,3 +823,84 @@ unsafeJoinPaths os =
     -- the leading separator from the first path. But it is not necessary.
     -- Instead we can avoid adding a separator if it is already present.
     Array.fromStream . Array.concatSepBy (charToWord $ primarySeparator os)
+
+-- | Check two paths for byte level equality. This is the most strict path
+-- equality check.
+--
+-- >>> :{
+--  eqPath a b = Common.eqPathBytes (packPosix a) (packPosix b)
+-- :}
+--
+-- >>> eqPath "x//y"  "x/y"
+-- False
+--
+-- >>> eqPath "x/./y"  "x/y"
+-- False
+--
+-- >>> eqPath "x\\y" "x/y"
+-- False
+--
+-- >>> eqPath "./file"  "file"
+-- False
+--
+-- >>> eqPath "file/"  "file"
+-- False
+--
+eqPathBytes :: Array a -> Array a -> Bool
+eqPathBytes = Array.byteEq
+
+-- | Checks two paths for logical equality. It performs some normalizations on
+-- the paths being compared e.g. it drops redundant path separators
+-- between path segments and redundant "/./" components. However, it keeps a
+-- leading "./" as well as a trailing "/" in the path. In other words, it does
+-- not drop the distinction of current directory relative path vs path segments
+-- (@./x vs x@) and directory paths from files (@x/ vs x@).
+--
+-- >>> :{
+--  eqPosix a b = Common.eqPathStrict Posix (packPosix a) (packPosix b)
+--  eqWindows a b = Common.eqPathStrict Windows (packWindows a) (packWindows b)
+-- :}
+--
+-- >>> eqPosix "x//y"  "x/y"
+-- True
+--
+-- >>> eqPosix "x/./y"  "x/y"
+-- True
+--
+-- >>> eqWindows "x\\y" "x/y"
+-- True
+--
+-- >>> eqPosix "./file"  "file"
+-- False
+--
+-- >>> eqPosix "file/"  "file"
+-- False
+--
+eqPathStrict :: (Integral a, Unbox a) => OS -> Array a -> Array a -> Bool
+eqPathStrict = undefined
+
+-- | Like eqPathStrict except that a leading "./" as well as a trailing "/" in
+-- the path is dropped before comparison.
+--
+-- >>> :{
+--  eqPosix a b = Common.eqPathLax Posix (packPosix a) (packPosix b)
+--  eqWindows a b = Common.eqPathLax Windows (packWindows a) (packWindows b)
+-- :}
+--
+-- >>> eqPosix "x//y"  "x/y"
+-- True
+--
+-- >>> eqPosix "x/./y"  "x/y"
+-- True
+--
+-- >>> eqWindows "x\\y" "x/y"
+-- True
+--
+-- >>> eqPosix "./file"  "file"
+-- True
+--
+-- >>> eqPosix "file/"  "file"
+-- True
+--
+eqPathLax :: (Integral a, Unbox a) => OS -> Array a -> Array a -> Bool
+eqPathLax = undefined