Org reader: restructure output of captioned code blocks

The Div wrapper of code blocks with captions now has the class
"captioned-content". The caption itself is added as a Plain block
inside a Div of class "caption". This makes it easier to write filters
which match on captioned code blocks. Existing filters will need to be
updated.

Closes: #6977

src/Text/Pandoc/Readers/Org/Blocks.hs

@@ -294,24 +294,22 @@ verseBlock blockType = try $ do
 codeBlock :: PandocMonad m => BlockAttributes -> Text -> OrgParser m (F Blocks)
 codeBlock blockAttrs blockType = do
   skipSpaces
-  (classes, kv)     <- codeHeaderArgs <|> (mempty <$ ignHeaders)
-  content           <- rawBlockContent blockType
-  resultsContent    <- option mempty babelResultsBlock
-  let id'            = fromMaybe mempty $ blockAttrName blockAttrs
-  let codeBlck       = B.codeBlockWith ( id', classes, kv ) content
-  let labelledBlck   = maybe (pure codeBlck)
-                             (labelDiv codeBlck)
-                             (blockAttrCaption blockAttrs)
+  (classes, kv)  <- codeHeaderArgs <|> (mempty <$ ignHeaders)
+  content        <- rawBlockContent blockType
+  resultsContent <- option mempty babelResultsBlock
+  let identifier = fromMaybe mempty $ blockAttrName blockAttrs
+  let codeBlk    = B.codeBlockWith (identifier, classes, kv) content
+  let wrap       = maybe pure addCaption (blockAttrCaption blockAttrs)
   return $
-    (if exportsCode kv    then labelledBlck   else mempty) <>
+    (if exportsCode kv    then wrap codeBlk   else mempty) <>
     (if exportsResults kv then resultsContent else mempty)
  where
-   labelDiv :: Blocks -> F Inlines -> F Blocks
-   labelDiv blk value =
-     B.divWith nullAttr <$> (mappend <$> labelledBlock value <*> pure blk)
+   addCaption :: F Inlines -> Blocks -> F Blocks
+   addCaption caption blk = B.divWith ("", ["captioned-content"], [])
+                         <$> (mkCaptionBlock caption <> pure blk)
 
-   labelledBlock :: F Inlines -> F Blocks
-   labelledBlock = fmap (B.plain . B.spanWith ("", ["label"], []))
+   mkCaptionBlock :: F Inlines -> F Blocks
+   mkCaptionBlock = fmap (B.divWith ("", ["caption"], []) . B.plain)
 
    exportsResults :: [(Text, Text)] -> Bool
    exportsResults = maybe False (`elem` ["results", "both"]) . lookup "exports"

test/Tests/Readers/Org/Block/CodeBlock.hs

@@ -185,10 +185,10 @@ tests =
                 , "#+end_src"
                 ] =?>
       divWith
-         nullAttr
+         ("", ["captioned-content"], [] )
          (mappend
-          (plain $ spanWith ("", ["label"], [])
-                            (spcSep [ "Functor", "laws", "in", "Haskell" ]))
+          (divWith ("", ["caption"], []) $
+           plain (spcSep [ "Functor", "laws", "in", "Haskell" ]))
           (codeBlockWith ("functor-laws", ["haskell"], [])
                          (T.unlines [ "fmap id = id"
                                     , "fmap (p . q) = (fmap p) . (fmap q)"