Options: Changed `writerSourceDir` to `writerSourceURL` (now a Maybe).

Previously we used to store the directory of the first input file,
even if it was local, and used this as a base directory for
finding images in ODT, EPUB, Docx, and PDF.

This has been confusing to many users.  It seems better to look for
images relative to the current working directory, even if the first
file argument is in another directory.

writerSourceURL is set to 'Just url' when the first command-line
argument is an absolute URL.  (So, relative links will be resolved
in relation to the first page.)  Otherwise, 'Nothing'.

The ODT, EPUB, Docx, and PDF writers have been modified accordingly.

Note that this change may break some existing workflows.  If you
have been assuming that relative links will be interpreted relative
to the directory of the first file argument, you'll need to
make that the current directory before running pandoc.

Closes #942.

1 files changed, 7 insertions, 14 deletions

diff --git a/src/Text/Pandoc/Writers/EPUB.hs b/src/Text/Pandoc/Writers/EPUB.hs
index fa2b45036..ac0e7610c 100644
--- a/src/Text/Pandoc/Writers/EPUB.hs
+++ b/src/Text/Pandoc/Writers/EPUB.hs
@@ -55,7 +55,7 @@ import Text.Pandoc.UUID
 import Text.Pandoc.Writers.HTML
 import Text.Pandoc.Writers.Markdown ( writePlain )
 import Data.Char ( toLower )
-import Network.URI ( isAbsoluteURI, unEscapeString )
+import Network.URI ( unEscapeString )
 import Text.Pandoc.MIME (getMimeType)
 #if MIN_VERSION_base(4,6,0)
 #else
@@ -93,7 +93,6 @@ writeEPUB opts doc@(Pandoc meta _) = do
                           then MathML Nothing
                           else writerHTMLMathMethod opts
                   , writerWrapText = False }
-  let sourceDir = writerSourceDirectory opts'
   let mbCoverImage = lookup "epub-cover-image" vars
 
   -- cover page
@@ -117,10 +116,10 @@ writeEPUB opts doc@(Pandoc meta _) = do
   -- handle pictures
   picsRef <- newIORef []
   Pandoc _ blocks <- walkM
-       (transformInline opts' sourceDir picsRef) doc
+       (transformInline opts' picsRef) doc
   pics <- readIORef picsRef
   let readPicEntry entries (oldsrc, newsrc) = do
-        res <- fetchItem sourceDir oldsrc
+        res <- fetchItem (writerSourceURL opts') oldsrc
         case res of
              Left _        -> do
               warn $ "Could not find image `" ++ oldsrc ++ "', skipping..."
@@ -414,19 +413,13 @@ showDateTimeISO8601 :: UTCTime -> String
 showDateTimeISO8601 = formatTime defaultTimeLocale "%FT%TZ"
 
 transformInline  :: WriterOptions
-                 -> FilePath
                  -> IORef [(FilePath, FilePath)] -- ^ (oldpath, newpath) images
                  -> Inline
                  -> IO Inline
-transformInline opts sourceDir picsRef (Image lab (src,tit))
-  | isAbsoluteURI src = do
-    raw <- makeSelfContained Nothing
-             $ writeHtmlInline opts (Image lab (src,tit))
-    return $ RawInline (Format "html") raw
-  | otherwise = do
+transformInline opts picsRef (Image lab (src,tit)) = do
     let src' = unEscapeString src
     pics <- readIORef picsRef
-    let oldsrc = sourceDir </> src'
+    let oldsrc = maybe src' (</> src) $ writerSourceURL opts
     let ext = takeExtension src'
     newsrc <- case lookup oldsrc pics of
                     Just n  -> return n
@@ -435,11 +428,11 @@ transformInline opts sourceDir picsRef (Image lab (src,tit))
                           modifyIORef picsRef ( (oldsrc, new): )
                           return new
     return $ Image lab (newsrc, tit)
-transformInline opts _ _ (x@(Math _ _))
+transformInline opts _ (x@(Math _ _))
   | WebTeX _ <- writerHTMLMathMethod opts = do
     raw <- makeSelfContained Nothing $ writeHtmlInline opts x
     return $ RawInline (Format "html") raw
-transformInline _ _ _ x = return x
+transformInline _ _ x = return x
 
 writeHtmlInline :: WriterOptions -> Inline -> String
 writeHtmlInline opts z = trimr $