Percent-encode more special characters in URLs.

HTML, LaTeX writers adjusted.
The special characters are '<','>','|','"','{','}','[',']','^', '`'.

Closes #1640, #2377.

3 files changed, 14 insertions, 9 deletions

diff --git a/src/Text/Pandoc/Shared.hs b/src/Text/Pandoc/Shared.hs
index 1fe3db5f7..1e06aa383 100644
--- a/src/Text/Pandoc/Shared.hs
+++ b/src/Text/Pandoc/Shared.hs
@@ -288,9 +288,12 @@ toRomanNumeral x =
               _ | x >= 1    -> "I" ++ toRomanNumeral (x - 1)
               _             -> ""
 
--- | Escape whitespace in URI.
+-- | Escape whitespace and some punctuation characters in URI.
 escapeURI :: String -> String
-escapeURI = escapeURIString (not . isSpace)
+escapeURI = escapeURIString (not . needsEscaping)
+  where needsEscaping c = isSpace c || c `elem`
+                           ['<','>','|','"','{','}','[',']','^', '`']
+
 
 -- | Convert tabs to spaces and filter out DOS line endings.
 -- Tabs will be preserved if tab stop is set to 0.
diff --git a/src/Text/Pandoc/Writers/LaTeX.hs b/src/Text/Pandoc/Writers/LaTeX.hs
index f424d8d4a..0caa80795 100644
--- a/src/Text/Pandoc/Writers/LaTeX.hs
+++ b/src/Text/Pandoc/Writers/LaTeX.hs
@@ -242,7 +242,7 @@ stringToLaTeX  ctx (x:xs) = do
        '^' -> "\\^{}" ++ rest
        '\\'| isUrl     -> '/' : rest  -- NB. / works as path sep even on Windows
            | otherwise -> "\\textbackslash{}" ++ rest
-       '|' -> "\\textbar{}" ++ rest
+       '|' | not isUrl -> "\\textbar{}" ++ rest
        '<' -> "\\textless{}" ++ rest
        '>' -> "\\textgreater{}" ++ rest
        '[' -> "{[}" ++ rest  -- to avoid interpretation as
@@ -848,17 +848,17 @@ inlineToLaTeX (Link txt (src, _)) =
   case txt of
         [Str x] | escapeURI x == src ->  -- autolink
              do modify $ \s -> s{ stUrl = True }
-                src' <- stringToLaTeX URLString src
+                src' <- stringToLaTeX URLString (escapeURI src)
                 return $ text $ "\\url{" ++ src' ++ "}"
         [Str x] | Just rest <- stripPrefix "mailto:" src,
                   escapeURI x == rest -> -- email autolink
              do modify $ \s -> s{ stUrl = True }
-                src' <- stringToLaTeX URLString src
+                src' <- stringToLaTeX URLString (escapeURI src)
                 contents <- inlineListToLaTeX txt
                 return $ "\\href" <> braces (text src') <>
                    braces ("\\nolinkurl" <> braces contents)
         _ -> do contents <- inlineListToLaTeX txt
-                src' <- stringToLaTeX URLString src
+                src' <- stringToLaTeX URLString (escapeURI src)
                 return $ text ("\\href{" ++ src' ++ "}{") <>
                          contents <> char '}'
 inlineToLaTeX (Image _ (source, _)) = do
@@ -866,7 +866,7 @@ inlineToLaTeX (Image _ (source, _)) = do
   let source' = if isURI source
                    then source
                    else unEscapeString source
-  source'' <- stringToLaTeX URLString source'
+  source'' <- stringToLaTeX URLString (escapeURI source')
   inHeading <- gets stInHeading
   return $
     (if inHeading then "\\protect\\includegraphics" else "\\includegraphics")
diff --git a/tests/Tests/Readers/Markdown.hs b/tests/Tests/Readers/Markdown.hs
index 5b39ae7e2..c24d2293f 100644
--- a/tests/Tests/Readers/Markdown.hs
+++ b/tests/Tests/Readers/Markdown.hs
@@ -66,9 +66,11 @@ bareLinkTests =
   , ("http://en.wikipedia.org/wiki/Sprite_(computer_graphics)",
       autolink "http://en.wikipedia.org/wiki/Sprite_(computer_graphics)")
   , ("http://en.wikipedia.org/wiki/Sprite_[computer_graphics]",
-      autolink "http://en.wikipedia.org/wiki/Sprite_[computer_graphics]")
+      link "http://en.wikipedia.org/wiki/Sprite_%5Bcomputer_graphics%5D" ""
+        (str "http://en.wikipedia.org/wiki/Sprite_[computer_graphics]"))
   , ("http://en.wikipedia.org/wiki/Sprite_{computer_graphics}",
-      autolink "http://en.wikipedia.org/wiki/Sprite_{computer_graphics}")
+      link "http://en.wikipedia.org/wiki/Sprite_%7Bcomputer_graphics%7D" ""
+        (str "http://en.wikipedia.org/wiki/Sprite_{computer_graphics}"))
   , ("http://example.com/Notification_Center-GitHub-20101108-140050.jpg",
       autolink "http://example.com/Notification_Center-GitHub-20101108-140050.jpg")
   , ("https://github.com/github/hubot/blob/master/scripts/cream.js#L20-20",