Lua: add field `chunk_template` to WriterOptions objects [API change]

The PathTemplate type exported from Text.Pandoc.Chunks is now an
instance of the ToJSON and FromJSON classes.

Closes: #8607

4 files changed, 15 insertions, 3 deletions

diff --git a/doc/lua-filters.md b/doc/lua-filters.md
index cf0a5ef25..ccd327b95 100644
--- a/doc/lua-filters.md
+++ b/doc/lua-filters.md
@@ -2115,6 +2115,9 @@ Pandoc writer options
 
 Fields:
 
+`chunk_template`
+:   Template used to generate chunked HTML filenames (string)
+
 `cite_method`
 :   How to print cites -- one of 'citeproc', 'natbib', or
     'biblatex' (string)
diff --git a/pandoc-lua-engine/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs b/pandoc-lua-engine/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
index 960972bed..4ef5ae14d 100644
--- a/pandoc-lua-engine/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
+++ b/pandoc-lua-engine/src/Text/Pandoc/Lua/Marshal/WriterOptions.hs
@@ -55,7 +55,12 @@ typeWriterOptions = deftype "WriterOptions"
     <#> udparam typeWriterOptions "opts" "options to print in native format"
     =#> functionResult pushString "string" "Haskell representation"
   ]
-  [ property "cite_method"
+  [ property "chunk_template"
+    "Templates used to generate chunked HTML filenames (string)"
+    (pushViaJSON, writerChunkTemplate)
+    (peekViaJSON, \opts x -> opts{ writerChunkTemplate = x })
+
+  , property "cite_method"
     "How to print cites"
     (pushViaJSON, writerCiteMethod)
     (peekViaJSON, \opts x -> opts{ writerCiteMethod = x })
diff --git a/pandoc-lua-engine/test/lua/module/globals.lua b/pandoc-lua-engine/test/lua/module/globals.lua
index 72edef036..19fee3e92 100644
--- a/pandoc-lua-engine/test/lua/module/globals.lua
+++ b/pandoc-lua-engine/test/lua/module/globals.lua
@@ -8,6 +8,9 @@ local assert = tasty.assert
 -- WriterOptions and its components. UPDATE THE DOCS if anything changes.
 return {
   group 'PANDOC_WRITER_OPTIONS' {
+    test('chunk_template', function ()
+      assert.are_equal(type(PANDOC_WRITER_OPTIONS.chunk_template), 'string')
+    end),
     test('cite_method', function ()
       assert.are_equal(type(PANDOC_WRITER_OPTIONS.cite_method), 'string')
     end),
diff --git a/src/Text/Pandoc/Chunks.hs b/src/Text/Pandoc/Chunks.hs
index 2447deb72..bd34cc6d5 100644
--- a/src/Text/Pandoc/Chunks.hs
+++ b/src/Text/Pandoc/Chunks.hs
@@ -1,5 +1,4 @@
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TupleSections #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE FlexibleContexts #-}
@@ -27,9 +26,11 @@ module Text.Pandoc.Chunks
   , tocToList
   , SecInfo(..)
   ) where
+
 import Text.Pandoc.Definition
 import Text.Pandoc.Shared (makeSections, stringify, inlineListToIdentifier)
 import Text.Pandoc.Walk (Walkable(..))
+import Data.Aeson (FromJSON, ToJSON)
 import Data.Text (Text)
 import Text.Printf (printf)
 import Data.Maybe (fromMaybe, isNothing)
@@ -257,7 +258,7 @@ resolvePathTemplate (PathTemplate templ) chunknum headingText ident secnum =
 -- @"section-1.2-introduction.html"@.
 newtype PathTemplate =
   PathTemplate { unPathTemplate :: Text }
-  deriving (Show, IsString, Data, Typeable, Generic)
+  deriving (Show, IsString, Data, Typeable, Generic, ToJSON, FromJSON)
 
 -- | A part of a document (typically a chapter or section, or
 -- the part of a section before its subsections).