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lib/SlackBuilder/Trans.hs

@@ -10,6 +10,7 @@ module SlackBuilder.Trans
     ) where
 
 import Control.Monad.Trans.Reader (ReaderT(..), asks)
+import Data.ByteString (ByteString)
 import Data.Text (Text)
 import qualified Data.Text as Text
 import SlackBuilder.Config
@@ -20,11 +21,14 @@ import System.FilePath ((</>))
 import Text.URI (URI)
 import qualified Text.URI as URI
 import qualified Codec.Compression.Lzma as Lzma
+import Text.Megaparsec (ParseErrorBundle(..), errorBundlePretty)
+import Conduit (Void)
 
 data SlackBuilderException
     = UpdaterNotFound Text
     | UnsupportedUrlType URI
     | LzmaDecompressionFailed Lzma.LzmaRet
+    | MalformedInfoFile (ParseErrorBundle ByteString Void)
     deriving Show
 
 instance Exception SlackBuilderException
@@ -55,6 +59,8 @@ instance Exception SlackBuilderException
         "No progress is possible"
     displayException (LzmaDecompressionFailed Lzma.LzmaRetProgError) =
         "Programming error"
+    displayException (MalformedInfoFile errorBundle) =
+        errorBundlePretty errorBundle
  
 newtype SlackBuilderT a = SlackBuilderT
     { runSlackBuilderT :: ReaderT Settings IO a