normalize: Normalize spaces too.

In normal form, Space elements only occur to separate two non-Space
elements.  So, we never have [Space], or [, ..., Space].

src/Tests/Shared.hs

@@ -10,6 +10,8 @@ tests :: [Test]
 tests = [ testGroup "normalize"
           [ property "p_normalize_blocks_rt" p_normalize_blocks_rt
           , property "p_normalize_inlines_rt" p_normalize_inlines_rt
+          , property "p_normalize_no_trailing_spaces"
+              p_normalize_no_trailing_spaces
           ]
         ]
 
@@ -19,3 +21,6 @@ p_normalize_blocks_rt bs = normalize bs == normalize (normalize bs)
 p_normalize_inlines_rt :: [Inline] -> Bool
 p_normalize_inlines_rt ils = normalize ils == normalize (normalize ils)
 
+p_normalize_no_trailing_spaces :: [Inline] -> Bool
+p_normalize_no_trailing_spaces ils = null ils' || last ils' /= Space
+  where ils' = normalize $ ils ++ [Space]

src/Text/Pandoc/Shared.hs

@@ -243,10 +243,7 @@ orderedListMarkers (start, numstyle, numdelim) =
 -- remove empty Str elements.
 normalizeSpaces :: [Inline] -> [Inline]
 normalizeSpaces = cleanup . dropWhile isSpaceOrEmpty
-  where isSpaceOrEmpty Space = True
-        isSpaceOrEmpty (Str "") = True
-        isSpaceOrEmpty _ = False
-        cleanup [] = []
+ where  cleanup [] = []
         cleanup (Space:rest) = let rest' = dropWhile isSpaceOrEmpty rest
                                in  case rest' of
                                    []            -> []
@@ -254,13 +251,18 @@ normalizeSpaces = cleanup . dropWhile isSpaceOrEmpty
         cleanup ((Str ""):rest) = cleanup rest
         cleanup (x:rest) = x : cleanup rest
 
+isSpaceOrEmpty :: Inline -> Bool
+isSpaceOrEmpty Space = True
+isSpaceOrEmpty (Str "") = True
+isSpaceOrEmpty _ = False
+
 -- | Normalize @Pandoc@ document, consolidating doubled 'Space's,
 -- combining adjacent 'Str's and 'Emph's, remove 'Null's and
 -- empty elements, etc.
 normalize :: (Eq a, Data a) => a -> a
 normalize = topDown removeEmptyBlocks .
             topDown consolidateInlines .
-            bottomUp removeEmptyInlines
+            bottomUp (removeEmptyInlines . removeTrailingInlineSpaces)
 
 removeEmptyBlocks :: [Block] -> [Block]
 removeEmptyBlocks (Null : xs) = removeEmptyBlocks xs
@@ -284,6 +286,9 @@ removeEmptyInlines (Str "" : zs) = removeEmptyInlines zs
 removeEmptyInlines (x : xs) = x : removeEmptyInlines xs
 removeEmptyInlines [] = []
 
+removeTrailingInlineSpaces :: [Inline] -> [Inline]
+removeTrailingInlineSpaces = reverse . dropWhile isSpaceOrEmpty . reverse
+
 consolidateInlines :: [Inline] -> [Inline]
 consolidateInlines (Str x : ys) =
   case concat (x : map fromStr strs) of