Use newtype for Gzip

Author: pete-murphy

app/src/Fetch/Retry.purs

@@ -8,7 +8,7 @@ import Registry.App.Prelude
 
 import Effect.Aff (Error)
 import Effect.Aff as Aff
-import Fetch (class ToCoreRequestOptions, class ToRequestBody, HighlevelRequestOptions, Response, new)
+import Fetch (class ToCoreRequestOptions, HighlevelRequestOptions, Response, new)
 import Fetch (Response) as ReExport
 import Fetch.Core as Core
 import Fetch.Core.Request as CoreRequest
@@ -23,8 +23,7 @@ data RetryRequestError
 
 withRetryRequest
   :: forall input output thruIn thruOut headers @body
-   . ToRequestBody body
-  => Union input thruIn (HighlevelRequestOptions headers body)
+   . Union input thruIn (HighlevelRequestOptions headers body)
   => Union output thruOut CoreRequest.UnsafeRequestOptions
   => ToCoreRequestOptions input output
   => String
@@ -63,8 +62,7 @@ withRetryRequest url r =
 -- | https://github.com/rowtype-yoga/purescript-fetch/issues/9
 fetchBody
   :: forall input output @thruIn thruOut headers body
-   . ToRequestBody body
-  => Union input thruIn (HighlevelRequestOptions headers body)
+   . Union input thruIn (HighlevelRequestOptions headers body)
   => Union output thruOut CoreRequest.UnsafeRequestOptions
   => ToCoreRequestOptions input output
   => String

foreign/src/Foreign/Gzip.js

@@ -6,4 +6,3 @@ export const compressImpl = (input, onError, onBuffer) =>
   );
 
 export const toRequestBodyImpl = (a) => a;
-export const toBuffer = (a) => a;

foreign/src/Foreign/Gzip.purs

@@ -1,7 +1,6 @@
 module Registry.Foreign.Gzip
-  ( compress
-  , toBuffer
-  , Gzipped
+  ( Gzip(..)
+  , compress
   ) where
 
 import Prelude
@@ -15,18 +14,17 @@ import Fetch (class ToRequestBody)
 import Fetch.Core.RequestBody (RequestBody)
 import Node.Buffer (Buffer)
 
-foreign import compressImpl :: EffectFn3 String (EffectFn1 Error Unit) (EffectFn1 Gzipped Unit) Unit
+foreign import compressImpl :: EffectFn3 String (EffectFn1 Error Unit) (EffectFn1 Gzip Unit) Unit
 
-foreign import data Gzipped :: Type
+foreign import toRequestBodyImpl :: Buffer -> RequestBody
 
-foreign import toRequestBodyImpl :: Gzipped -> RequestBody
-foreign import toBuffer :: Gzipped -> Buffer
+newtype Gzip = Gzip Buffer
 
-instance ToRequestBody Gzipped where
-  toRequestBody = toRequestBodyImpl
+instance ToRequestBody Gzip where
+  toRequestBody (Gzip buffer) = toRequestBodyImpl buffer
 
 -- | Compress a string using gzip.
-compress :: forall m. MonadAff m => String -> m Gzipped
+compress :: forall m. MonadAff m => String -> m Gzip
 compress input = liftAff do
   makeAff \handle -> do
     runEffectFn3 compressImpl input

foreign/test/Foreign/Gzip.purs

@@ -6,6 +6,7 @@ import Data.Either (Either(..))
 import Node.FS.Aff as FS.Aff
 import Node.Library.Execa as Execa
 import Node.Path as Path
+import Registry.Foreign.Gzip (Gzip(..))
 import Registry.Foreign.Gzip as Gzip
 import Registry.Foreign.Tmp as Tmp
 import Registry.Test.Assert as Assert
@@ -19,7 +20,7 @@ spec = do
       let
         file = Path.concat [ tmp, "out.gz" ]
         contents = "<contents>"
-      buffer <- Gzip.toBuffer <$> Gzip.compress contents
+      Gzip buffer <- Gzip.compress contents
       FS.Aff.writeFile file buffer
       result <- _.result =<< Execa.execa "zcat" [ file ] identity
       (_.stdout <$> result) `Assert.shouldEqual` Right contents