Remove Google Lucky for non-existing interwiki links

For compatibility renderer will return string '' of $shortcut and $url instead of NULL when seeing a non-existing interwiki link. In the meantime, media and link output in xhtml renderer is adjusted, to show title text instead when src/href is null. In interwiki case, the title will be the "reference" part of the interwiki link.

This makes it possible to also support no URL cases in `interwiki.conf`. Before it will output a URL as `rawurlencode($reference)`, which doesn't make too much sense since it's encoded. However, I am not sure the use case under the current behavior (no URL, but text as `$reference`).

Docs needs to be added to warn renderer plugin developers of this situation.

This fixes #2588.

3 files changed, 20 insertions, 9 deletions

diff --git a/_test/tests/inc/parser/renderer_resolveinterwiki.test.php b/_test/tests/inc/parser/renderer_resolveinterwiki.test.php
index 2cd23dfaa..8ace02fab 100644
--- a/_test/tests/inc/parser/renderer_resolveinterwiki.test.php
+++ b/_test/tests/inc/parser/renderer_resolveinterwiki.test.php
@@ -47,9 +47,9 @@ class Test_resolveInterwiki extends DokuWikiTest {
         $shortcut = 'nonexisting';
         $reference = 'foo @+%/';
         $url = $Renderer->_resolveInterWiki($shortcut, $reference);
-        $expected = 'https://www.google.com/search?q=foo%20%40%2B%25%2F&btnI=lucky';
 
-        $this->assertEquals($expected, $url);
+        $this->assertEquals('', $url);
+        $this->assertEquals('', $shortcut);
     }
 
 }
diff --git a/inc/parser/renderer.php b/inc/parser/renderer.php
index 6a76d4861..fe4eb7908 100644
--- a/inc/parser/renderer.php
+++ b/inc/parser/renderer.php
@@ -846,9 +846,9 @@ abstract class Doku_Renderer extends Plugin {
         if(isset($this->interwiki[$shortcut])) {
             $url = $this->interwiki[$shortcut];
         } else {
-            // Default to Google I'm feeling lucky
-            $url      = 'https://www.google.com/search?q={URL}&btnI=lucky';
-            $shortcut = 'go';
+            // not parsable interwiki outputs '' to make sure string manipluation works
+            $shortcut = '';
+            $url      = '';
         }
 
         //split into hash and url part
@@ -880,8 +880,9 @@ abstract class Doku_Renderer extends Plugin {
                 '{PATH}' => $parsed['path'],
                 '{QUERY}' => $parsed['query'] ,
             ]);
-        } else {
-            //default
+        } else if($url != '') {
+            // make sure when no url is defined, we keep it null
+            // default
             $url = $url.rawurlencode($reference);
         }
         //handle as wiki links
diff --git a/inc/parser/xhtml.php b/inc/parser/xhtml.php
index 388e1b7ad..f448d8a25 100644
--- a/inc/parser/xhtml.php
+++ b/inc/parser/xhtml.php
@@ -1062,11 +1062,13 @@ class Doku_Renderer_xhtml extends Doku_Renderer {
         $link['url']   = $url;
         $link['title'] = htmlspecialchars($link['url']);
 
-        //output formatted
+        // output formatted
         if($returnonly) {
+            if($url == '') return $link['name'];
             return $this->_formatLink($link);
         } else {
-            $this->doc .= $this->_formatLink($link);
+            if($url == '') $this->doc .= $link['name'];
+            else $this->doc .= $this->_formatLink($link);
         }
     }
 
@@ -1248,9 +1250,17 @@ class Doku_Renderer_xhtml extends Doku_Renderer {
             list($shortcut, $reference) = explode('>', $src, 2);
             $exists = null;
             $src = $this->_resolveInterWiki($shortcut, $reference, $exists);
+            if($src == '' && empty($title)){
+                // make sure at least something will be shown in this case
+                $title = $reference;
+            }
         }
         list($src, $hash) = explode('#', $src, 2);
         $noLink = false;
+        if($src == '') {
+            // only output plaintext without link if there is no src
+            $noLink = true;
+        }
         $render = ($linking == 'linkonly') ? false : true;
         $link   = $this->_getMediaLinkConf($src, $title, $align, $width, $height, $cache, $render);