"yii\console\controllers\MessageController" has been fixed.

framework/yii/console/controllers/MessageController.php

@@ -55,7 +55,8 @@ class MessageController extends Controller
 	 *    directory 'sourcePath/a/b'.
 	 *  - translator: the name of the function for translating messages.
 	 *    Defaults to 'Yii::t'. This is used as a mark to find messages to be
-	 *    translated.
+	 *    translated. Accepts both string for single function name or array for
+	 *    multiple function names.
 	 *  - overwrite: if message file must be overwritten with the merged messages.
 	 *  - removeOld: if message no longer needs translation it will be removed,
 	 *    instead of being enclosed between a pair of '@@' marks.
@@ -133,10 +134,14 @@ class MessageController extends Controller
 	{
 		echo "Extracting messages from $fileName...\n";
 		$subject = file_get_contents($fileName);
+		$messages = array();
+		if (!is_array($translator)) {
+			$translator = array($translator);
+		}
+		foreach ($translator as $currentTranslator) {
 			$n = preg_match_all(
-			'/\b' . $translator . '\s*\(\s*(\'.*?(?<!\\\\)\'|".*?(?<!\\\\)")\s*,\s*(\'.*?(?<!\\\\)\'|".*?(?<!\\\\)")\s*[,\)]/s',
+				'/\b' . $currentTranslator . '\s*\(\s*(\'.*?(?<!\\\\)\'|".*?(?<!\\\\)")\s*,\s*(\'.*?(?<!\\\\)\'|".*?(?<!\\\\)")\s*[,\)]/s',
 				$subject, $matches, PREG_SET_ORDER);
-		$messages = array();
 			for ($i = 0; $i < $n; ++$i) {
 				if (($pos = strpos($matches[$i][1], '.')) !== false) {
 					$category = substr($matches[$i][1], $pos + 1, -1);
@@ -146,6 +151,7 @@ class MessageController extends Controller
 				$message = $matches[$i][2];
 				$messages[$category][] = eval("return $message;"); // use eval to eliminate quote escape
 			}
+		}
 		return $messages;
 	}
 
@@ -172,7 +178,7 @@ class MessageController extends Controller
 			$merged = array();
 			$untranslated = array();
 			foreach ($messages as $message) {
-				if (!empty($translated[$message])) {
+				if (array_key_exists($message, $translated) && strlen($translated[$message]) > 0) {
 					$merged[$message] = $translated[$message];
 				} else {
 					$untranslated[] = $message;

tests/unit/framework/console/controllers/MessageControllerTest.php

@@ -17,6 +17,9 @@ class MessageControllerTest extends TestCase
 	{
 		$this->sourcePath = Yii::getAlias('@yiiunit/runtime/test_source');
 		$this->createDir($this->sourcePath);
+		if (!file_exists($this->sourcePath)) {
+			$this->markTestIncomplete('Unit tests runtime directory should have writable permissions!');
+		}
 		$this->messagePath = Yii::getAlias('@yiiunit/runtime/test_messages');
 		$this->createDir($this->messagePath);
 		$this->configFileName = Yii::getAlias('@yiiunit/runtime') . DIRECTORY_SEPARATOR . 'message_controller_test_config.php';
@@ -81,8 +84,9 @@ class MessageControllerTest extends TestCase
 	protected function createMessageController()
 	{
 		$module = $this->getMock('yii\\base\\Module', array('fake'), array('console'));
-		$command = new MessageController('message', $module);
-		return $command;
+		$messageController = new MessageController('message', $module);
+		$messageController->interactive = false;
+		return $messageController;
 	}
 
 	/**
@@ -166,8 +170,6 @@ class MessageControllerTest extends TestCase
 
 	public function testCreateTranslation()
 	{
-		$this->markTestIncomplete('MessageController is incomplete');
-
 		$language = 'en';
 
 		$category = 'test_category';