Add System.File fRead function

libs/base/System/File/ReadWrite.idr

@@ -3,6 +3,7 @@ module System.File.ReadWrite
 import public Data.Fuel
 
 import Data.List
+import Data.SnocList
 
 import System.File.Handle
 import public System.File.Error
@@ -113,6 +114,21 @@ fEOF (FHandle f)
     = do res <- primIO (prim__eof f)
          pure (res /= 0)
 
+||| Read all the remaining contents of a file handle
+export
+covering
+fRead : HasIO io => (h : File) -> io (Either FileError String)
+fRead h = fRead' h [<]
+  where
+    fRead' : HasIO io' => (h : File) -> (acc : SnocList String) -> io' (Either FileError String)
+    fRead' h acc = do
+      if !(fEOF h)
+         then pure $ Right $ concat acc
+         else do
+             Right line <- fGetLine h
+                | Left err => pure $ Left err
+             fRead' h $ acc :< line
+
 ||| Delete the file at the given name.
 |||
 ||| @ fname the file to delete

tests/base/system_file_fRead/ReadFile.idr

@@ -0,0 +1,9 @@
+import System.File
+
+main : IO ()
+main = do
+    Right f <- openFile "sampleFile.txt" Read
+        | Left err => printLn err
+    Right contents <- fRead f
+        | Left err => printLn err
+    printLn contents

tests/base/system_file_fRead/expected

@@ -0,0 +1,3 @@
+1/1: Building ReadFile (ReadFile.idr)
+Main> "Hello, world\nLorem ipsum\n"
+Main> Bye for now!

tests/base/system_file_fRead/input

@@ -0,0 +1,2 @@
+:exec main
+:q

tests/base/system_file_fRead/run

@@ -0,0 +1,3 @@
+rm -rf build
+
+$1 --no-color --console-width 0 --no-banner ReadFile.idr < input

tests/base/system_file_fRead/sampleFile.txt

@@ -0,0 +1,2 @@
+Hello, world
+Lorem ipsum