(bug 6640) add a prefix= parameter to creation inputboxes; using a intercept/munge/redirect method stolen from Wikia.

InputBox.classes.php

@@ -325,6 +325,13 @@ class InputBox {
 				'value' => $this->mSummary,
 			)
 		);
+		$htmlOut .= Xml::openElement( 'input',
+			array(
+				'type' => 'hidden',
+				'name' => 'prefix',
+				'value' => $this->mPrefix,
+			)
+		);
 		$htmlOut .= Xml::openElement( 'input',
 			array(
 				'type' => 'hidden',

InputBox.hooks.php

@@ -31,4 +31,50 @@ class InputBoxHooks {
 		// Return output
 		return $inputBox->render();
 	}
+	
+	/**
+	 * <inputbox type=create...> sends requests with action=edit, and 
+	 * possibly a &prefix=Foo.  So we pick that up here, munge prefix 
+	 * and title together, and redirect back out to the real page
+	 * @param $output OutputPage
+	 * @param $article Article
+	 * @param $title Title
+	 * @param $user User
+	 * @param $request WebRequest 
+	 * @param $wiki MediaWiki
+	 * @return True
+	 */
+	public static function onMediaWikiPerformAction( 
+		$output, 
+		$article, 
+		$title, 
+		$user, 
+		$request, 
+		$wiki )
+	{
+		$action = $wiki->getVal( 'Action' );
+		if( $action !== 'edit' ){
+			# not our problem
+			return true;
+		}
+		if( $request->getText( 'prefix', '' ) === '' ){
+			# Fine
+			return true;
+		}
+		
+		$params = $request->getValues();
+		$title = $params['prefix'] . @$params['title'];
+		unset( $params['prefix'] );
+		unset( $params['title'] );
+		$url = "?title=$title";
+		foreach( $params as $key => $value ){
+			if( $key ){
+				$url .= "&{$key}={$value}";
+			}
+		}
+		
+		global $wgScript;
+		$output->redirect( $wgScript . $url, '301' );
+		return false;
+	}
 }

InputBox.php

@@ -49,3 +49,4 @@ $wgAutoloadClasses['InputBox'] = $dir . 'InputBox.classes.php';
 
 // Register parser hook
 $wgHooks['ParserFirstCallInit'][] = 'InputBoxHooks::register';
+$wgHooks['MediaWikiPerformAction'][] = 'InputBoxHooks::onMediaWikiPerformAction';