HTML writer: Make header attributes work outside top level.

Previously they only appeared on top level header elements.
Now they work e.g. in blockquotes.

Closes #1711.

3 files changed, 18 insertions, 4 deletions

diff --git a/src/Text/Pandoc/Writers/HTML.hs b/src/Text/Pandoc/Writers/HTML.hs
index 1a00c7660..e261cfca8 100644
--- a/src/Text/Pandoc/Writers/HTML.hs
+++ b/src/Text/Pandoc/Writers/HTML.hs
@@ -73,11 +73,13 @@ data WriterState = WriterState
     , stQuotes           :: Bool    -- ^ <q> tag is used
     , stHighlighting     :: Bool    -- ^ Syntax highlighting is used
     , stSecNum           :: [Int]   -- ^ Number of current section
+    , stElement          :: Bool    -- ^ Processing an Element
     }
 
 defaultWriterState :: WriterState
 defaultWriterState = WriterState {stNotes= [], stMath = False, stQuotes = False,
-                                  stHighlighting = False, stSecNum = []}
+                                  stHighlighting = False, stSecNum = [],
+                                  stElement = False}
 
 -- Helpers to render HTML with the appropriate function.
 
@@ -280,7 +282,13 @@ elementToHtml slideLevel opts (Sec level num (id',classes,keyvals) title' elemen
   let titleSlide = slide && level < slideLevel
   header' <- if title' == [Str "\0"]  -- marker for hrule
                 then return mempty
-                else blockToHtml opts (Header level' (id',classes,keyvals) title')
+                else do
+                  modify (\st -> st{ stElement = True})
+                  res <- blockToHtml opts
+                           (Header level' (id',classes,keyvals) title')
+                  modify (\st -> st{ stElement = False})
+                  return res
+
   let isSec (Sec _ _ _ _ _) = True
       isSec (Blk _)         = False
   let isPause (Blk x) = x == Para [Str ".",Space,Str ".",Space,Str "."]
@@ -491,7 +499,7 @@ blockToHtml opts (BlockQuote blocks) =
      else do
        contents <- blockListToHtml opts blocks
        return $ H.blockquote $ nl opts >> contents >> nl opts
-blockToHtml opts (Header level (_,classes,_) lst) = do
+blockToHtml opts (Header level attr@(_,classes,_) lst) = do
   contents <- inlineListToHtml opts lst
   secnum <- liftM stSecNum get
   let contents' = if writerNumberSections opts && not (null secnum)
@@ -499,7 +507,9 @@ blockToHtml opts (Header level (_,classes,_) lst) = do
                      then (H.span ! A.class_ "header-section-number" $ toHtml
                           $ showSecNum secnum) >> strToHtml " " >> contents
                      else contents
-  return $ case level of
+  inElement <- gets stElement
+  return $ (if inElement then id else addAttrs opts attr)
+         $ case level of
               1 -> H.h1 contents'
               2 -> H.h2 contents'
               3 -> H.h3 contents'
diff --git a/tests/markdown-reader-more.native b/tests/markdown-reader-more.native
index b4303dacb..00313a0ac 100644
--- a/tests/markdown-reader-more.native
+++ b/tests/markdown-reader-more.native
@@ -79,6 +79,8 @@
 ,Para [Str "Link",Space,Str "to",Space,Link [Str "Explicit",Space,Str "header",Space,Str "attributes"] ("#foobar",""),Str "."]
 ,Para [Str "But",Space,Str "this",Space,Str "is",Space,Str "not",Space,Str "a",Space,Str "link",Space,Str "to",Space,Link [Str "My",Space,Str "other",Space,Str "header"] ("/foo",""),Str ",",Space,Str "since",Space,Str "the",Space,Str "reference",Space,Str "is",Space,Str "defined."]
 ,Header 2 ("foobar",["baz"],[("key","val")]) [Str "Explicit",Space,Str "header",Space,Str "attributes"]
+,BlockQuote
+ [Header 2 ("foobar",["baz"],[("key","val")]) [Str "Header",Space,Str "attributes",Space,Str "inside",Space,Str "block",Space,Str "quote"]]
 ,Header 2 ("line-blocks",[],[]) [Str "Line",Space,Str "blocks"]
 ,Para [Str "But",Space,Str "can",Space,Str "a",Space,Str "bee",Space,Str "be",Space,Str "said",Space,Str "to",Space,Str "be",LineBreak,Str "\160\160\160\160or",Space,Str "not",Space,Str "to",Space,Str "be",Space,Str "an",Space,Str "entire",Space,Str "bee,",LineBreak,Str "\160\160\160\160\160\160\160\160when",Space,Str "half",Space,Str "the",Space,Str "bee",Space,Str "is",Space,Str "not",Space,Str "a",Space,Str "bee,",LineBreak,Str "\160\160\160\160\160\160\160\160\160\160\160\160due",Space,Str "to",Space,Str "some",Space,Str "ancient",Space,Str "injury?"]
 ,Para [Str "Continuation",Space,Str "line",LineBreak,Str "\160\160and",Space,Str "another"]
diff --git a/tests/markdown-reader-more.txt b/tests/markdown-reader-more.txt
index 4c3c99cf7..ea4fc9cad 100644
--- a/tests/markdown-reader-more.txt
+++ b/tests/markdown-reader-more.txt
@@ -176,6 +176,8 @@ But this is not a link to [My other header], since the reference is defined.
 
 ## Explicit header attributes {#foobar .baz key="val"}
 
+> ## Header attributes inside block quote {#foobar .baz key="val"}
+
 ## Line blocks
 
 | But can a bee be said to be