Markdown reader: use title of implicit figure as short caption.

src/Text/Pandoc/Readers/Markdown.hs

@@ -1092,7 +1092,9 @@ implicitFigure (ident, classes, attribs) capt url title =
               _               -> capt
       attribs' = filter ((/= "alt") . fst) attribs
       figattr = (ident, mempty, mempty)
-      caption = B.simpleCaption $ B.plain capt
+      caption = if T.null title
+                then B.simpleCaption $ B.plain capt
+                else B.caption (Just . B.toList $ B.text title) $ B.plain capt
       figbody = B.plain $ B.imageWith ("", classes, attribs') url title alt
   in B.figureWith figattr caption figbody
 

src/Text/Pandoc/Writers/Markdown.hs

@@ -672,21 +672,22 @@ blockToMarkdown' opts (Figure figattr capt body) = do
   let combinedAttr imgattr = case imgattr of
         ("", cls, kv) | (figid, [], []) <- figattr -> Just (figid, cls, kv)
         _ -> Nothing
-  let combinedAlt alt = case capt of
+  let combinedAlt alt title = case capt of
         Caption Nothing [] -> if null alt
                               then Just [Str "image"]
                               else Just alt
-        Caption Nothing [Plain captInlines]
-          | captInlines == alt -> Just captInlines
+        Caption short [Plain captInlines]
+          | captInlines == alt
+          , title == maybe "" stringify short -> Just captInlines
         _ -> Nothing
   case body of
     [Plain [Image imgAttr alt (src, ttl)]]
       | isEnabled Ext_implicit_figures opts
-      , Just descr    <- combinedAlt alt
+      , Just descr    <- combinedAlt alt ttl
       , Just imgAttr' <- combinedAttr imgAttr
       , isEnabled Ext_link_attributes opts || imgAttr' == nullAttr
         -> do
-          -- use implicit figures if possible
+          -- Lossless representation as implicit figure is possible
           let tgt' = (src, fromMaybe ttl $ T.stripPrefix "fig:" ttl)
           contents <- inlineListToMarkdown opts [Image imgAttr' descr tgt']
           return $ contents <> blankline

test/testsuite.native

@@ -1908,7 +1908,17 @@ Pandoc
       ]
   , Figure
       ( "" , [] , [] )
-      (Caption Nothing [ Plain [ Str "lalune" ] ])
+      (Caption
+         (Just
+            [ Str "Voyage"
+            , Space
+            , Str "dans"
+            , Space
+            , Str "la"
+            , Space
+            , Str "Lune"
+            ])
+         [ Plain [ Str "lalune" ] ])
       [ Plain
           [ Image
               ( "" , [] , [] )

test/writer.context

@@ -931,7 +931,7 @@ or here: <http://example.com/>
 
 From \quotation{Voyage dans la Lune} by Georges Melies (1902):
 
-\startplacefigure[title={lalune}]
+\startplacefigure[title={lalune},list={Voyage dans la Lune}]
 {\externalfigure[lalune.jpg]}
 \stopplacefigure
 

test/writer.latex

@@ -951,7 +951,7 @@ From ``Voyage dans la Lune'' by Georges Melies (1902):
 \begin{figure}
 \centering
 \includegraphics{lalune.jpg}
-\caption{lalune}
+\caption[Voyage dans la Lune]{lalune}
 \end{figure}
 
 Here is a movie \includegraphics{movie.jpg} icon.

test/writer.native

@@ -1843,7 +1843,17 @@ Pandoc
       ]
   , Figure
       ( "" , [] , [] )
-      (Caption Nothing [ Plain [ Str "lalune" ] ])
+      (Caption
+         (Just
+            [ Str "Voyage"
+            , Space
+            , Str "dans"
+            , Space
+            , Str "la"
+            , Space
+            , Str "Lune"
+            ])
+         [ Plain [ Str "lalune" ] ])
       [ Plain
           [ Image
               ( "" , [] , [] )