DocBook reader: ensure that first and last names are separated.

Closes #6541.

src/Text/Pandoc/Readers/DocBook.hs

@@ -600,16 +600,24 @@ addMetadataFromElement e = do
          Nothing -> return ()
          Just z  -> addMetaField "author" z
     addMetaField "subtitle" e
-    addMetaField "author" e
+    addAuthor e
     addMetaField "date" e
     addMetaField "release" e
     addMetaField "releaseinfo" e
     return mempty
-  where addMetaField fieldname elt =
-            case filterChildren (named fieldname) elt of
-                   []  -> return ()
-                   [z] -> getInlines z >>= addMeta fieldname
-                   zs  -> mapM getInlines zs >>= addMeta fieldname
+  where
+   addAuthor elt =
+     case filterChildren (named "author") elt of
+       [] -> return ()
+       [z] -> fromAuthor z >>= addMeta "author"
+       zs  -> mapM fromAuthor zs >>= addMeta "author"
+   fromAuthor elt =
+     mconcat . intersperse space <$> mapM getInlines (elChildren elt)
+   addMetaField fieldname elt =
+     case filterChildren (named fieldname) elt of
+       []  -> return ()
+       [z] -> getInlines z >>= addMeta fieldname
+       zs  -> mapM getInlines zs >>= addMeta fieldname
 
 addMeta :: PandocMonad m => ToMetaValue a => Text -> a -> DB m ()
 addMeta field val = modify (setMeta field val)

test/command/6541.md

@@ -0,0 +1,27 @@
+```
+% pandoc -f docbook -t markdown -s
+<?xml version="1.0"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<book>
+
+<bookinfo>
+<title>Title</title>
+<author>
+<firstname>Firstname</firstname><surname>Lastname</surname>
+</author>
+<releaseinfo>1.17</releaseinfo>
+</bookinfo>
+
+<para>Text.</para>
+
+</book>
+^D
+---
+author: Firstname Lastname
+releaseinfo: 1.17
+title: Title
+---
+
+Text.
+```