Docx reader: Pick table width from the longest row or header

This change is intended to preserve as much of the table content as
possible

Closes #4360

1 files changed, 9 insertions, 5 deletions

diff --git a/src/Text/Pandoc/Readers/Docx.hs b/src/Text/Pandoc/Readers/Docx.hs
index c24c43901..098759a61 100644
--- a/src/Text/Pandoc/Readers/Docx.hs
+++ b/src/Text/Pandoc/Readers/Docx.hs
@@ -642,7 +642,7 @@ bodyPartToBlocks (ListItem pPr _ _ _ parparts) =
     bodyPartToBlocks $ Paragraph pPr' parparts
 bodyPartToBlocks (Tbl _ _ _ []) =
   return $ para mempty
-bodyPartToBlocks (Tbl cap _ look (r:rs)) = do
+bodyPartToBlocks (Tbl cap _ look parts@(r:rs)) = do
   let caption = text cap
       (hdr, rows) = case firstRowFormatting look of
         True | null rs -> (Nothing, [r])
@@ -651,10 +651,14 @@ bodyPartToBlocks (Tbl cap _ look (r:rs)) = do
 
   cells <- mapM rowToBlocksList rows
 
-  let width = case cells of
-        r':_ -> length r'
-        -- shouldn't happen
-        []   -> 0
+  let width = maybe 0 maximum $ nonEmpty $ map rowLength parts
+      -- Data.List.NonEmpty is not available with ghc 7.10 so we roll out
+      -- our own, see
+      -- https://github.com/jgm/pandoc/pull/4361#issuecomment-365416155
+      nonEmpty [] = Nothing
+      nonEmpty l  = Just l
+      rowLength :: Row -> Int
+      rowLength (Row c) = length c
 
   hdrCells <- case hdr of
     Just r' -> rowToBlocksList r'