Use the new builders, modify readers to preserve empty headers

The Builder.simpleTable now only adds a row to the TableHead when the
given header row is not null. This uncovered an inconsistency in the
readers: some would unconditionally emit a header filled with empty
cells, even if the header was not present. Now every reader has the
conditional behaviour. Only the XWiki writer depended on the header
row being always present; it now pads its head as necessary.

1 files changed, 6 insertions, 3 deletions

diff --git a/src/Text/Pandoc/Readers/Textile.hs b/src/Text/Pandoc/Readers/Textile.hs
index a0680ac81..fef192fd3 100644
--- a/src/Text/Pandoc/Readers/Textile.hs
+++ b/src/Text/Pandoc/Readers/Textile.hs
@@ -377,10 +377,13 @@ table = try $ do
                              _ -> (mempty, rawrows)
   let nbOfCols = maximum $ map length (headers:rows)
   let aligns = map minimum $ transpose $ map (map (snd . fst)) (headers:rows)
-  return $ B.table caption
+  let toRow = Row nullAttr . map B.simpleCell
+      toHeaderRow l = if null l then [] else [toRow l]
+  return $ B.table (B.simpleCaption $ B.plain caption)
     (zip aligns (replicate nbOfCols ColWidthDefault))
-    (map snd headers)
-    (map (map snd) rows)
+    (TableHead nullAttr $ toHeaderRow $ map snd headers)
+    [TableBody nullAttr 0 [] $ map (toRow . map snd) rows]
+    (TableFoot nullAttr [])
 
 -- | Ignore markers for cols, thead, tfoot.
 ignorableRow :: PandocMonad m => ParserT Text ParserState m ()