RST writer: render Divs with admonition classes as admonitions.

Also omit Div with class "admonition-title". These are generated
by the RST reader and should be omitted on round-trip.

Closes #4833.

1 files changed, 12 insertions, 3 deletions

diff --git a/src/Text/Pandoc/Writers/RST.hs b/src/Text/Pandoc/Writers/RST.hs
index 7a299e4e9..005db5e77 100644
--- a/src/Text/Pandoc/Writers/RST.hs
+++ b/src/Text/Pandoc/Writers/RST.hs
@@ -211,12 +211,21 @@ blockToRST :: PandocMonad m
            => Block         -- ^ Block element
            -> RST m Doc
 blockToRST Null = return empty
+blockToRST (Div ("",["admonition-title"],[]) _) = return empty
+  -- this is generated by the rst reader and can safely be
+  -- omitted when we're generating rst
 blockToRST (Div (ident,classes,_kvs) bs) = do
   contents <- blockListToRST bs
-  let classes' = filter (/= "container") classes
+  let admonitions = ["attention","caution","danger","error","hint",
+                     "important","note","tip","warning","admonition"]
+  let admonition = case classes of
+                        (cl:_)
+                          | cl `elem` admonitions
+                          -> ".. " <> text cl <> "::"
+                        cls -> ".. container::" <> space <>
+                                   text (unwords (filter (/= "container") cls))
   return $ blankline $$
-           (".. container::" <> space <>
-              text (unwords classes')) $$
+           admonition $$
            (if null ident
                then blankline
                else "   :name: " <> text ident $$ blankline) $$