From f6edf03303d909332896f93ddf81d5f693c670aa Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Tue, 7 Jul 2026 20:58:33 +0200
Subject: [PATCH] Shared: Improve `makeSections`.

Previously it would sometimes create doubled section divs.
By leaving the inner heading's id on the heading itself, and
then consolidating the inner and outer section divs, we can
avoid this undesirable result.

Closes #11745.
---
 src/Text/Pandoc/Shared.hs | 21 +++++++++++++++------
 test/command/11745.md     | 26 ++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 6 deletions(-)
 create mode 100644 test/command/11745.md

diff --git a/src/Text/Pandoc/Shared.hs b/src/Text/Pandoc/Shared.hs
index 41eefd198..12e74b53b 100644
--- a/src/Text/Pandoc/Shared.hs
+++ b/src/Text/Pandoc/Shared.hs
@@ -569,16 +569,25 @@ makeSectionsWithOffsets numoffsets numbering mbBaseLevel bs =
       | all (\case
                Header level' _ _ -> level' > level
                _                 -> True) ys
-      , "column" `notElem` dclasses
-      , "columns" `notElem` dclasses
-      , "fragment" `notElem` dclasses = do
+      , "section" `elem` dclasses
+        || ("column" `notElem` dclasses &&
+            "columns" `notElem` dclasses &&
+            "fragment" `notElem` dclasses &&
+            "cell" `notElem` dclasses) = do
     inner <- go (Header level hattr title':ys)
     rest <- go xs
     return $
       case inner of
-            [Div divattr'@(dident',_,_) zs]
-              | T.null dident || T.null dident' || dident == dident'
-              -> Div (combineAttr divattr' divattr) zs : rest
+            [Div divattr'@(dident',_,_) zs@(Header level' hattr' title'' : zs')]
+              | dident == dident'
+                -> Div (combineAttr divattr' divattr) zs : rest
+              | (_,dclasses',dkvs) <- combineAttr divattr' divattr
+              , ("",hclasses,hkvs) <- hattr'
+                -> if T.null dident
+                      then Div (dident',dclasses',dkvs) zs : rest
+                      else Div (dident,dclasses',dkvs)
+                             (Header level' (dident',hclasses,hkvs) title''
+                               : zs') : rest
             _ -> Div divattr inner : rest
   go (Div attr xs : rest) = do
     xs' <- go xs
diff --git a/test/command/11745.md b/test/command/11745.md
new file mode 100644
index 000000000..07e4fa42c
--- /dev/null
+++ b/test/command/11745.md
@@ -0,0 +1,26 @@
+```
+% pandoc --section-divs
+# Book Title
+
+::: {#ch1 .section}
+## Chapter 1
+Hello world.
+:::
+
+::: {#ch2 .section}
+## Chapter 2
+Goodbye world.
+:::
+^D
+<section id="book-title" class="level1">
+<h1>Book Title</h1>
+<section id="ch1" class="level2">
+<h2 id="chapter-1">Chapter 1</h2>
+<p>Hello world.</p>
+</section>
+<section id="ch2" class="level2">
+<h2 id="chapter-2">Chapter 2</h2>
+<p>Goodbye world.</p>
+</section>
+</section>
+```