RST reader: fix hyperlink aliases.

`link <google_>`_

    .. _google: https://google.com

is really a reference link.

Closes #3283.

src/Text/Pandoc/Readers/RST.hs

@@ -1120,14 +1120,22 @@ explicitLink = try $ do
   notFollowedBy (char '`') -- `` marks start of inline code
   label' <- trimInlines . mconcat <$>
              manyTill (notFollowedBy (char '`') >> inline) (char '<')
-  src <- manyTill (noneOf ">\n") (char '>')
+  src <- trim <$> manyTill (noneOf ">\n") (char '>')
   skipSpaces
   string "`_"
   optional $ char '_' -- anonymous form
   let label'' = if label' == mempty
                    then B.str src
                    else label'
-  return $ B.link (escapeURI $ trim src) "" label''
+  -- `link <google_>` is a reference link to _google!
+  (src',tit,attr) <- case reverse src of
+                          '_':xs -> do
+                            keyTable <- stateKeys <$> getState
+                            case M.lookup (toKey (reverse xs)) keyTable of
+                                 Nothing -> fail "no corresponding key"
+                                 Just ((s,t),a) -> return (s,t,a)
+                          _ -> return (src, "", nullAttr)
+  return $ B.linkWith attr (escapeURI src') tit label''
 
 referenceLink :: RSTParser Inlines
 referenceLink = try $ do

tests/rst-reader.native

@@ -214,6 +214,7 @@ Pandoc (Meta {unMeta = fromList [("author",MetaList [MetaInlines [Str "John",Spa
 ,Para [Str "Explicit",Space,Str "with",Space,Str "no",Space,Str "label:",Space,Link ("",[],[]) [Str "foo"] ("foo",""),Str "."]
 ,Para [Str "Two",Space,Str "anonymous",Space,Str "links:",Space,Link ("",[],[]) [Str "the",Space,Str "first"] ("/url1/",""),Space,Str "and",Space,Link ("",[],[]) [Str "the",Space,Str "second"] ("/url2/","")]
 ,Para [Str "Reference",Space,Str "links:",Space,Link ("",[],[]) [Str "link1"] ("/url1/",""),Space,Str "and",Space,Link ("",[],[]) [Str "link2"] ("/url2/",""),Space,Str "and",Space,Link ("",[],[]) [Str "link1"] ("/url1/",""),Space,Str "again."]
+,Para [Str "Another",Space,Link ("",[],[]) [Str "style",Space,Str "of",Space,Str "reference",Space,Str "link"] ("/url1/",""),Str "."]
 ,Para [Str "Here\8217s",Space,Str "a",Space,Link ("",[],[]) [Str "link",Space,Str "with",Space,Str "an",Space,Str "ampersand",Space,Str "in",Space,Str "the",Space,Str "URL"] ("http://example.com/?foo=1&bar=2",""),Str "."]
 ,Para [Str "Here\8217s",Space,Str "a",Space,Str "link",Space,Str "with",Space,Str "an",Space,Str "amersand",Space,Str "in",Space,Str "the",Space,Str "link",Space,Str "text:",Space,Link ("",[],[]) [Str "AT&T"] ("/url/",""),Str "."]
 ,Para [Str "Autolinks:",Space,Link ("",[],[]) [Str "http://example.com/?foo=1&bar=2"] ("http://example.com/?foo=1&bar=2",""),Space,Str "and",Space,Link ("",[],[]) [Str "nobody@nowhere.net"] ("mailto:nobody@nowhere.net",""),Str "."]

tests/rst-reader.rst

@@ -390,6 +390,8 @@ Reference links:  `link1`_ and `link2`_ and link1_ again.
 .. _link1: /url1/
 .. _`link2`: /url2/
 
+Another `style of reference link <link1_>`_.
+
 Here's a `link with an ampersand in the URL`_.
 
 Here's a link with an amersand in the link text: `AT&T </url/>`_.