never executed always true always false

    1 module CommandLine.InfoFormatter
    2     ( ToConsole(..), Loggable(..)
    3     , onInfo, approve
    4     , ExecuteMode(..), init, done
    5     ) where
    6 
    7 import Prelude hiding (init, putStrLn)
    8 
    9 import CommandLine.World (World)
   10 import qualified CommandLine.World as World
   11 import Control.Monad.State
   12 import Data.Text (Text)
   13 import qualified Data.Text.Encoding as T
   14 import qualified Data.Aeson as Aeson
   15 import qualified Data.ByteString.Char8 as B
   16 import qualified Data.ByteString.Lazy.Char8 as LB
   17 import qualified Data.Aeson.Encoding.Internal as AesonInternal
   18 
   19 
   20 class ToConsole a where
   21     toConsole :: a -> Text
   22 
   23 
   24 class ToConsole a => Loggable a where
   25     jsonInfoMessage :: a -> Maybe Aeson.Encoding
   26 
   27 
   28 onInfo :: (World m, Loggable info) => ExecuteMode -> info -> StateT Bool m ()
   29 onInfo mode info =
   30     case mode of
   31         ForMachine ->
   32             maybe (lift $ return ()) json $ jsonInfoMessage info
   33 
   34         ForHuman usingStdout ->
   35             lift $ putStrLn' usingStdout (toConsole info)
   36 
   37 
   38 approve :: (World m, ToConsole prompt) => ExecuteMode -> Bool -> prompt -> m Bool
   39 approve mode autoYes prompt =
   40     case autoYes of
   41         True -> return True
   42 
   43         False ->
   44             case mode of
   45                 ForMachine -> return False
   46 
   47                 ForHuman usingStdout ->
   48                     putStrLn' usingStdout (toConsole prompt) *> World.getYesOrNo
   49 
   50 
   51 data ExecuteMode
   52     = ForMachine
   53     | ForHuman { _usingStdout :: Bool }
   54 
   55 
   56 init :: World m => ExecuteMode -> (m (), Bool)
   57 init ForMachine = (World.putStr "[", False)
   58 init (ForHuman _) = (return (), undefined)
   59 
   60 
   61 done :: World m => ExecuteMode -> Bool -> m ()
   62 done ForMachine _ = World.putStrLn "]"
   63 done (ForHuman _) _ = return ()
   64 
   65 
   66 putStrLn' :: World m => Bool -> Text -> m ()
   67 putStrLn' usingStdout =
   68     -- we log to stdout unless it is being used for file output (in that case, we log to stderr)
   69     case usingStdout of
   70         True -> World.putStrLnStderr
   71         False -> World.putStrLn
   72 
   73 
   74 json :: World m => Aeson.Encoding -> StateT Bool m ()
   75 json jsvalue =
   76     do
   77         printComma <- get
   78         when printComma (lift $ World.putStr ",")
   79         lift $ World.putStrLn $ T.decodeUtf8 $ B.concat $ LB.toChunks $ AesonInternal.encodingToLazyByteString jsvalue
   80         put True