Handle empty tables

Don't try to estimate column widths if it leads to division by zero.

1 files changed, 4 insertions, 2 deletions

diff --git a/Pancake/Rendering.hs b/Pancake/Rendering.hs
index 0149655..6c6f4e2 100644
--- a/Pancake/Rendering.hs
+++ b/Pancake/Rendering.hs
@@ -436,8 +436,10 @@ renderBlock (P.Table caption aligns widths headers rows) = do
   ws <- if widthsAreSet then pure widths else do
     lens <- map sum . transpose <$> mapM
       (mapM (fmap (length . unstyled . concat . rLines) . renderCell 80)) rows
-    pure $ map (\l -> fromIntegral l / fromIntegral (sum lens) * 0.7
-                      + 1 / fromIntegral (length lens) * 0.3) lens
+    pure $ map (\l -> if sum lens == 0 || length lens == 0
+                      then 0
+                      else fromIntegral l / fromIntegral (sum lens) * 0.7
+                           + 1 / fromIntegral (length lens) * 0.3) lens
   let withHead = if all null headers then id else (headers :)
   mapM_ (\r -> renderBlock P.HorizontalRule >> tableRow ws r) (withHead rows)
   renderBlock P.HorizontalRule