Improve emailAddress in Text.Pandoc.Parsing.

Previously the parser would accept characters in domains
that are illegal in domains, and this sometimes caused it
to gobble bits of the following text.

Closes #7398.

Note that this change, by itself, caused some txt2tag reader
tests to fail. txt2tags allows bare email addresses with
a following form query.  So, in addition to the change
to emailAddress, we modify the txt2tags parser so it can
still handle these cases.

src/Text/Pandoc/Parsing.hs

@@ -693,13 +693,12 @@ emailAddress = try $ toResult <$> mailbox <*> (char '@' *> domain)
        mailbox           = intercalate "." <$> (emailWord `sepBy1'` dot)
        domain            = intercalate "." <$> (subdomain `sepBy1'` dot)
        dot               = char '.'
-       subdomain         = many1 $ alphaNum <|> innerPunct
+       subdomain         = many1 $ alphaNum <|> innerPunct (=='-')
        -- this excludes some valid email addresses, since an
        -- email could contain e.g. '__', but gives better results
        -- for our purposes, when combined with markdown parsing:
-       innerPunct        = try (satisfy (\c -> isEmailPunct c || c == '@')
-                                 <* notFollowedBy space
-                                 <* notFollowedBy (satisfy isPunctuation))
+       innerPunct f      = try (satisfy f
+                                 <* notFollowedBy (satisfy (not . isAlphaNum)))
        -- technically an email address could begin with a symbol,
        -- but allowing this creates too many problems.
        -- See e.g. https://github.com/jgm/pandoc/issues/2940

src/Text/Pandoc/Readers/Txt2Tags.hs

@@ -478,9 +478,29 @@ macro = try $ do
 -- raw URLs in text are automatically linked
 url :: T2T Inlines
 url = try $ do
-  (rawUrl, escapedUrl) <- try uri <|> emailAddress
+  (rawUrl, escapedUrl) <- try uri <|> emailAddress'
   return $ B.link rawUrl "" (B.str escapedUrl)
 
+emailAddress' :: T2T (Text, Text)
+emailAddress' = do
+  (base, mailURI) <- emailAddress
+  query <- option "" emailQuery
+  return (base <> query, mailURI <> query)
+
+emailQuery :: T2T Text
+emailQuery = do
+  char '?'
+  parts <- kv `sepBy1` (char '&')
+  return $ "?" <> T.intercalate "&" parts
+
+kv :: T2T Text
+kv = do
+  k <- T.pack <$> many1 alphaNum
+  char '='
+  let vchar = alphaNum <|> try (oneOf "%._/~:,=$@&+-;*" <* lookAhead alphaNum)
+  v <- T.pack <$> many1 vchar
+  return (k <> "=" <> v)
+
 uri :: T2T (Text, Text)
 uri = try $ do
   address <- t2tURI