Muse writer: insert two blanklines between lists of the same type (#3844)

2 files changed, 96 insertions, 1 deletions

diff --git a/src/Text/Pandoc/Writers/Muse.hs b/src/Text/Pandoc/Writers/Muse.hs
index 0383d9d86..3a5eefc18 100644
--- a/src/Text/Pandoc/Writers/Muse.hs
+++ b/src/Text/Pandoc/Writers/Muse.hs
@@ -102,12 +102,34 @@ pandocToMuse (Pandoc meta blocks) = do
        Nothing  -> return main
        Just tpl -> renderTemplate' tpl context
 
+-- | Helper function for flatBlockListToMuse
+-- | Render all blocks and insert blank lines between the first two
+catWithBlankLines :: PandocMonad m
+                  => [Block]       -- ^ List of block elements
+                  -> Int           -- ^ Number of blank lines
+                  -> StateT WriterState m Doc
+catWithBlankLines (b : bs) n = do
+  b' <- blockToMuse b
+  bs' <- flatBlockListToMuse bs
+  return $ b' <> blanklines n <> bs'
+catWithBlankLines _ _ = error "Expected at least one block"
+
 -- | Convert list of Pandoc block elements to Muse
 -- | without setting stTopLevel.
 flatBlockListToMuse :: PandocMonad m
                 => [Block]       -- ^ List of block elements
                 -> StateT WriterState m Doc
-flatBlockListToMuse blocks = cat <$> mapM blockToMuse blocks
+flatBlockListToMuse bs@(BulletList _ : BulletList _ : _) = catWithBlankLines bs 2
+flatBlockListToMuse bs@(OrderedList (_, style1, _) _ : OrderedList (_, style2, _) _ : _) =
+  catWithBlankLines bs (if style1' == style2' then 2 else 0)
+    where
+      style1' = normalizeStyle style1
+      style2' = normalizeStyle style2
+      normalizeStyle DefaultStyle = Decimal
+      normalizeStyle s = s
+flatBlockListToMuse bs@(DefinitionList _ : DefinitionList _ : _) = catWithBlankLines bs 2
+flatBlockListToMuse bs@(_ : _) = catWithBlankLines bs 0
+flatBlockListToMuse [] = return mempty
 
 -- | Convert list of Pandoc block elements to Muse.
 blockListToMuse :: PandocMonad m
diff --git a/test/Tests/Writers/Muse.hs b/test/Tests/Writers/Muse.hs
index ebe5d45cd..5291a5ef0 100644
--- a/test/Tests/Writers/Muse.hs
+++ b/test/Tests/Writers/Muse.hs
@@ -93,6 +93,79 @@ tests = [ testGroup "block elements"
                                               , " third definition :: third description"
                                               ]
               ]
+            -- Test that lists of the same type and style are separated with two blanklines
+            , testGroup "sequential lists"
+              [ "bullet lists" =:
+                bulletList [ para $ text "First"
+                           , para $ text "Second"
+                           , para $ text "Third"
+                           ] <>
+                bulletList [ para $ text "Fourth"
+                           , para $ text "Fifth"
+                           ] =?>
+                unlines [ " - First"
+                        , " - Second"
+                        , " - Third"
+                        , ""
+                        , ""
+                        , " - Fourth"
+                        , " - Fifth"
+                        ]
+              , "ordered lists of the same style" =:
+                orderedListWith (1, UpperRoman, DefaultDelim) [ para $ text "First"
+                                                              , para $ text "Second"
+                                                              ] <>
+                orderedListWith (1, UpperRoman, DefaultDelim) [ para $ text "Third"
+                                                              , para $ text "Fourth"
+                                                              ] =?>
+                unlines [ " I.  First"
+                        , " II. Second"
+                        , ""
+                        , ""
+                        , " I.  Third"
+                        , " II. Fourth"
+                        ]
+              , "ordered lists with equal styles" =:
+                orderedList [ para $ text "First"
+                            , para $ text "Second"
+                            ] <>
+                orderedListWith (1, Decimal, DefaultDelim) [ para $ text "Third"
+                                                           , para $ text "Fourth"
+                                                           ] =?>
+                unlines [ " 1. First"
+                        , " 2. Second"
+                        , ""
+                        , ""
+                        , " 1. Third"
+                        , " 2. Fourth"
+                        ]
+              , "bullet and ordered lists" =:
+                bulletList [ para $ text "First"
+                           , para $ text "Second"
+                           ] <>
+                orderedListWith (1, UpperRoman, DefaultDelim) [ para $ text "Third"
+                                                              , para $ text "Fourth"
+                                                              ] =?>
+                unlines [ " - First"
+                        , " - Second"
+                        , ""
+                        , " I.  Third"
+                        , " II. Fourth"
+                        ]
+              , "different style ordered lists" =:
+                orderedListWith (1, UpperRoman, DefaultDelim) [ para $ text "First"
+                                                              , para $ text "Second"
+                                                              ] <>
+                orderedListWith (1, Decimal, DefaultDelim) [ para $ text "Third"
+                                                           , para $ text "Fourth"
+                                                           ] =?>
+                unlines [ " I.  First"
+                        , " II. Second"
+                        , ""
+                        , " 1. Third"
+                        , " 2. Fourth"
+                        ]
+              ]
             , testGroup "nested lists"
               [ "nested ordered list" =: orderedList [ plain $ text "First outer"
                                                      , plain (text "Second outer:") <>