From 16c1de1906597a3bbb849b5700b77d0e95f4d53d Mon Sep 17 00:00:00 2001
From: Ryan Scott <rscott@galois.com>
Date: Thu, 5 Oct 2023 05:45:44 -0700
Subject: [PATCH] Support building with scotty-0.20

Fixes #98.
---
 Changelog.md       | 3 +++
 Graphics/Blank.hs  | 9 ++++++++-
 blank-canvas.cabal | 7 +++++--
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/Changelog.md b/Changelog.md
index 06cf69d..c178a71 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,6 @@
+### 0.7.4 [2023.10.05]
+* Support building with `scotty-0.20`.
+
 ### 0.7.3
 * Allow building with GHC 9.0.
 
diff --git a/Graphics/Blank.hs b/Graphics/Blank.hs
index 1df682c..9a7efcb 100644
--- a/Graphics/Blank.hs
+++ b/Graphics/Blank.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# LANGUAGE OverloadedStrings #-}
@@ -291,7 +292,7 @@ blankCanvas opts actions = do
 
         -- There has to be a better way of doing this, using function, perhaps?
         get (Scotty.regex "^/(.*)$") $ do
-          fileName :: Text <- Scotty.param "1"
+          fileName :: Text <- captureParam "1"
           db <- liftIO $ atomically $ readTVar $ locals
           if fileName `S.member` db
           then do
@@ -307,6 +308,12 @@ blankCanvas opts actions = do
                $ setTimeout 5
                $ defaultSettings
                ) app
+  where
+#if MIN_VERSION_scotty(0,20,0)
+    captureParam = Scotty.captureParam
+#else
+    captureParam = Scotty.param
+#endif
 
 -- | Sends a set of canvas commands to the 'Canvas'. Attempts
 -- to common up as many commands as possible. Should not crash.
diff --git a/blank-canvas.cabal b/blank-canvas.cabal
index e9c2458..8f33f94 100644
--- a/blank-canvas.cabal
+++ b/blank-canvas.cabal
@@ -1,5 +1,5 @@
 Name:                blank-canvas
-Version:             0.7.3
+Version:             0.7.4
 Synopsis:            HTML5 Canvas Graphics Library
 
 Description:      @blank-canvas@ is a Haskell binding to the complete
@@ -89,7 +89,10 @@ Library
                        http-types            >= 0.8     && < 0.13,
                        mime-types            >= 0.1.0.3 && < 0.2,
                        kansas-comet          >= 0.4     && < 0.5,
-                       scotty                >= 0.10    && < 0.13,
+                       -- TODO: Eventually, we should bump the lower version
+                       -- bounds to >=0.20 so that we can remove some CPP in
+                       -- Graphics.Blank.
+                       scotty                >= 0.10    && < 0.21,
                        semigroups            >= 0.18    && < 1,
                        stm                   >= 2.2     && < 2.6,
                        text                  >= 1.1     && < 2.2,