From 9fa5e768156a27d56cdfa73bbcf52b0456ee26b7 Mon Sep 17 00:00:00 2001
From: Toni Dietze <Flupp@users.noreply.github.com>
Date: Thu, 9 Feb 2023 11:19:31 +0100
Subject: [PATCH] DocBook writer: output identifiers of figure blocks

---
 src/Text/Pandoc/Writers/DocBook.hs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/Text/Pandoc/Writers/DocBook.hs b/src/Text/Pandoc/Writers/DocBook.hs
index 787401152430..09c2ae4fe256 100644
--- a/src/Text/Pandoc/Writers/DocBook.hs
+++ b/src/Text/Pandoc/Writers/DocBook.hs
@@ -320,7 +320,7 @@ blockToDocBook opts (Table _ blkCapt specs thead tbody tfoot) = do
   return $ inTagsIndented tableType $ captionDoc $$
         inTags True "tgroup" [("cols", tshow (length aligns))] (
          coltags $$ head' $$ body')
-blockToDocBook opts (Figure attr capt@(Caption _ caption) body) = do
+blockToDocBook opts (Figure attr@(id', _, _) capt@(Caption _ caption) body) = do
   -- TODO: probably better to handle nested figures as mediaobject
   let isAcceptable = \case
         Table {}  -> All False
@@ -344,10 +344,13 @@ blockToDocBook opts (Figure attr capt@(Caption _ caption) body) = do
                    DocBook4 -> pure mempty -- docbook4 requires media
                    DocBook5 -> blocksToDocBook opts body
       mediaobjects <- mapM toMediaobject body
+      version <- ask
+      let idAttr = [ (idName version, writerIdentifierPrefix opts <> id')
+                   | not (T.null id') ]
       return $
         if isEmpty $ mconcat mediaobjects
         then mempty -- figures must have at least some content
-        else inTagsIndented "figure" $
+        else inTags True "figure" idAttr $
              inTagsSimple "title" title $$
              mconcat mediaobjects