From 5c48ec11eea5891287f97d7d660fe1c762f624a5 Mon Sep 17 00:00:00 2001
From: Marco Zocca <marco.zocca@unfoldml.com>
Date: Wed, 27 Sep 2023 21:15:35 +0200
Subject: [PATCH 1/2] add comments and remove unused RequestBodyState

---
 Web/Scotty/Internal/Types.hs | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/Web/Scotty/Internal/Types.hs b/Web/Scotty/Internal/Types.hs
index 8bfd8023..76a7723b 100644
--- a/Web/Scotty/Internal/Types.hs
+++ b/Web/Scotty/Internal/Types.hs
@@ -72,12 +72,15 @@ type Application m = Request -> m Response
 
 ------------------ Scotty Request Body --------------------
 
-data BodyChunkBuffer = BodyChunkBuffer { hasFinishedReadingChunks :: Bool
-                                       , chunksReadSoFar :: [BS.ByteString] }
-
-data BodyInfo = BodyInfo { bodyInfoReadProgress :: MVar Int
+data BodyChunkBuffer = BodyChunkBuffer { hasFinishedReadingChunks :: Bool -- ^ whether we've reached the end of the stream yet
+                                       , chunksReadSoFar :: [BS.ByteString]
+                                       }
+-- | The key part of having two MVars is that we can "clone" the BodyInfo to create a copy where the index is reset to 0, but the chunk cache is the same. Passing a cloned BodyInfo into each matched route allows them each to start from the first chunk if they call bodyReader.
+--
+-- Introduced in (#308)
+data BodyInfo = BodyInfo { bodyInfoReadProgress :: MVar Int -- ^ index into the stream read so far
                          , bodyInfoChunkBuffer :: MVar BodyChunkBuffer
-                         , bodyInfoDirectChunkRead :: IO BS.ByteString
+                         , bodyInfoDirectChunkRead :: IO BS.ByteString -- ^ can be called to get more chunks
                          }
 
 --------------- Scotty Applications -----------------
@@ -154,10 +157,6 @@ data ActionEnv = Env { getReq       :: Request
                      , getFiles     :: [File]
                      }
 
-data RequestBodyState = BodyUntouched
-                      | BodyCached LBS8.ByteString [BS.ByteString] -- whole body, chunks left to stream
-                      | BodyCorrupted
-
 data BodyPartiallyStreamed = BodyPartiallyStreamed deriving (Show, Typeable)
 
 instance E.Exception BodyPartiallyStreamed

From 5d6494c5cf3dcf35da0e2d0c80024397c0540056 Mon Sep 17 00:00:00 2001
From: Marco Zocca <marco.zocca@unfoldml.com>
Date: Wed, 27 Sep 2023 21:17:40 +0200
Subject: [PATCH 2/2] changelog

---
 changelog.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/changelog.md b/changelog.md
index 23a5c719..0f6ffa0a 100644
--- a/changelog.md
+++ b/changelog.md
@@ -3,6 +3,7 @@
 * Disambiguate request parameters (#204). Adjust the `Env` type to have three [Param] fields instead of one, add `captureParam`, `formParam`, `queryParam` and the associated `captureParams`, `formParams`, `queryParams`. Add deprecation notices to `param` and `params`.
 * Add `Scotty.Cookie` module.
 * Change body parsing behaviour such that calls to 'next' don't result in POST request bodies disappearing (#147).
+* (Internal) Remove unused type RequestBodyState (#313)
 
 ## 0.12.1 [2022.11.17]
 * Fix CPP bug that prevented tests from building on Windows.