Add new unexported module T.P.XMLParser.

This exports functions that uses xml-conduit's parser to
produce an xml-light Element or [Content].  This allows
existing pandoc code to use a better parser without
much modification.

The new parser is used in all places where xml-light's
parser was previously used.  Benchmarks show a significant
performance improvement in parsing XML-based formats
(especially ODT and FB2).

Note that the xml-light types use String, so the
conversion from xml-conduit types involves a lot
of extra allocation.  It would be desirable to
avoid that in the future by gradually switching
to using xml-conduit directly. This can be done
module by module.

The new parser also reports errors, which we report
when possible.

A new constructor PandocXMLError has been added to
PandocError in T.P.Error [API change].

Closes #7091, which was the main stimulus.

These changes revealed the need for some changes
in the tests.  The docbook-reader.docbook test
lacked definitions for the entities it used; these
have been added. And the docx golden tests have been
updated, because the new parser does not preserve
the order of attributes.

Add entity defs to docbook-reader.docbook.

Update golden tests for docx.

1 files changed, 14 insertions, 10 deletions

diff --git a/src/Text/Pandoc/Readers/Odt.hs b/src/Text/Pandoc/Readers/Odt.hs
index 9943d3147..85308deb1 100644
--- a/src/Text/Pandoc/Readers/Odt.hs
+++ b/src/Text/Pandoc/Readers/Odt.hs
@@ -15,6 +15,7 @@ module Text.Pandoc.Readers.Odt ( readOdt ) where
 
 import Codec.Archive.Zip
 import qualified Text.XML.Light as XML
+import Text.Pandoc.XMLParser (parseXMLElement)
 
 import qualified Data.ByteString.Lazy as B
 
@@ -66,18 +67,18 @@ bytesToOdt bytes = case toArchiveOrFail bytes of
 
 --
 archiveToOdt :: Archive -> Either PandocError (Pandoc, MediaBag)
-archiveToOdt archive = either (Left. PandocParseError) Right $ do
-  let onFailure msg Nothing = Left msg
+archiveToOdt archive = do
+  let onFailure msg Nothing = Left $ PandocParseError msg
       onFailure _   (Just x) = Right x
   contentEntry <- onFailure "Could not find content.xml"
                    (findEntryByPath "content.xml" archive)
   stylesEntry <- onFailure "Could not find styles.xml"
                    (findEntryByPath "styles.xml" archive)
-  contentElem <- onFailure "Could not find content element"
-                   (entryToXmlElem contentEntry)
-  stylesElem <- onFailure "Could not find styles element"
-                   (entryToXmlElem stylesEntry)
-  styles <- either (\_ -> Left "Could not read styles") Right
+  contentElem <- entryToXmlElem contentEntry
+  stylesElem <- entryToXmlElem stylesEntry
+  styles <- either
+               (\_ -> Left $ PandocParseError "Could not read styles")
+               Right
                (chooseMax (readStylesAt stylesElem ) (readStylesAt contentElem))
   let filePathIsOdtMedia :: FilePath -> Bool
       filePathIsOdtMedia fp =
@@ -85,10 +86,13 @@ archiveToOdt archive = either (Left. PandocParseError) Right $ do
         in  (dir == "Pictures/") || (dir /= "./" && name == "content.xml")
   let media = filteredFilesFromArchive archive filePathIsOdtMedia
   let startState = readerState styles media
-  either (\_ -> Left "Could not convert opendocument") Right
+  either (\_ -> Left $ PandocParseError "Could not convert opendocument") Right
     (runConverter' read_body startState contentElem)
 
 
 --
-entryToXmlElem :: Entry -> Maybe XML.Element
-entryToXmlElem = XML.parseXMLDoc . UTF8.toStringLazy . fromEntry
+entryToXmlElem :: Entry -> Either PandocError XML.Element
+entryToXmlElem entry =
+  case parseXMLElement . UTF8.toTextLazy . fromEntry $ entry of
+    Right x  -> Right x
+    Left msg -> Left $ PandocXMLError (T.pack $ eRelativePath entry) msg