Relax upper bound for hslua, allow hslua-2.2. (#7929)

Lua 5.4 is used by default after this is merged. Packagers may still include Lua 5.3
instead by building pandoc with `--constraint='hslua <2.2'`.

Differences between 5.3 and 5.4 should not generally affect pandoc Lua filters.
See list of incompatible changes here  <https://www.lua.org/manual/5.4/manual.html#8.1>

3 files changed, 9 insertions, 0 deletions

diff --git a/src/Text/Pandoc/Lua/Marshal/ReaderOptions.hs b/src/Text/Pandoc/Lua/Marshal/ReaderOptions.hs
index 1b3acc076..bec7d81bf 100644
--- a/src/Text/Pandoc/Lua/Marshal/ReaderOptions.hs
+++ b/src/Text/Pandoc/Lua/Marshal/ReaderOptions.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE LambdaCase           #-}
 {-# LANGUAGE OverloadedStrings    #-}
 {-# LANGUAGE ScopedTypeVariables  #-}
@@ -21,7 +22,9 @@ module Text.Pandoc.Lua.Marshal.ReaderOptions
 
 import Data.Default (def)
 import HsLua as Lua
+#if !MIN_VERSION_hslua(2,2,0)
 import HsLua.Aeson (peekViaJSON, pushViaJSON)
+#endif
 import Text.Pandoc.Lua.Marshal.List (pushPandocList)
 import Text.Pandoc.Options (ReaderOptions (..))
 
diff --git a/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs b/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
index 639b85422..86df682c5 100644
--- a/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
+++ b/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE LambdaCase           #-}
 {-# LANGUAGE OverloadedStrings    #-}
 {-# LANGUAGE ScopedTypeVariables  #-}
@@ -20,7 +21,9 @@ module Text.Pandoc.Lua.Marshal.WriterOptions
 import Control.Applicative (optional)
 import Data.Default (def)
 import HsLua as Lua
+#if !MIN_VERSION_hslua(2,2,0)
 import HsLua.Aeson (peekViaJSON, pushViaJSON)
+#endif
 import Text.Pandoc.Lua.Marshal.List (pushPandocList)
 import Text.Pandoc.Lua.Marshal.Template (peekTemplate, pushTemplate)
 import Text.Pandoc.Options (WriterOptions (..))
diff --git a/src/Text/Pandoc/Lua/Writer/Classic.hs b/src/Text/Pandoc/Lua/Writer/Classic.hs
index 6b021911c..58f6efa33 100644
--- a/src/Text/Pandoc/Lua/Writer/Classic.hs
+++ b/src/Text/Pandoc/Lua/Writer/Classic.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                 #-}
 {-# LANGUAGE FlexibleContexts    #-}
 {-# LANGUAGE FlexibleInstances   #-}
 {-# LANGUAGE OverloadedStrings   #-}
@@ -24,7 +25,9 @@ import Data.Maybe (fromMaybe)
 import qualified Data.Text as T
 import Data.Text (Text, pack)
 import HsLua as Lua hiding (Operation (Div))
+#if !MIN_VERSION_hslua(2,2,0)
 import HsLua.Aeson (peekViaJSON)
+#endif
 import Text.DocLayout (literal, render)
 import Text.DocTemplates (Context)
 import Text.Pandoc.Definition