HTML reader/writer: better handling of "section" elements.

Previously `<section>` tags were just parsed as raw HTML
blocks.  With this change, section elements are parsed as
Div elements with the class "section".  The HTML writer will
use `<section>` tags to render these Divs in HTML5; otherwise
they will be rendered as `<div class="section">`.

Closes #2438.

1 files changed, 5 insertions, 2 deletions

diff --git a/src/Text/Pandoc/Writers/HTML.hs b/src/Text/Pandoc/Writers/HTML.hs
index a2778ea97..6218de324 100644
--- a/src/Text/Pandoc/Writers/HTML.hs
+++ b/src/Text/Pandoc/Writers/HTML.hs
@@ -448,12 +448,15 @@ blockToHtml opts (Para [Image txt (s,'f':'i':'g':':':tit)]) = do
 blockToHtml opts (Para lst) = do
   contents <- inlineListToHtml opts lst
   return $ H.p contents
-blockToHtml opts (Div attr@(_,classes,_) bs) = do
+blockToHtml opts (Div attr@(ident, classes, kvs) bs) = do
   let speakerNotes = "notes" `elem` classes
   -- we don't want incremental output inside speaker notes, see #1394
   let opts' = if speakerNotes then opts{ writerIncremental = False } else opts
   contents <- blockListToHtml opts' bs
   let contents' = nl opts >> contents >> nl opts
+  let (divtag, classes') = if writerHtml5 opts && "section" `elem` classes
+                              then (H5.section, filter (/= "section") classes)
+                              else (H.div, classes)
   return $
      if speakerNotes
         then case writerSlideVariant opts of
@@ -462,7 +465,7 @@ blockToHtml opts (Div attr@(_,classes,_) bs) = do
                                       ! (H5.customAttribute "role" "note")
                   NoSlides       -> addAttrs opts' attr $ H.div $ contents'
                   _              -> mempty
-        else addAttrs opts attr $ H.div $ contents'
+        else addAttrs opts (ident, classes', kvs) $ divtag $ contents'
 blockToHtml opts (RawBlock f str)
   | f == Format "html" = return $ preEscapedString str
   | f == Format "latex" =