[Translation] deprecate the backup feature

Author: xabbuh

CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+3.1.0
+-----
+
+ * Deprecated the backup feature of the file dumper classes.
+
 3.0.0
 -----
 

Dumper/FileDumper.php

@@ -73,6 +73,7 @@ public function dump(MessageCatalogue $messages, $options = array())
             $fullpath = $options['path'].'/'.$this->getRelativePath($domain, $messages->getLocale());
             if (file_exists($fullpath)) {
                 if ($this->backup) {
+                    @trigger_error('Creating a backup while dumping a message catalogue is deprecated since version 3.1 and will be removed in 4.0. Use TranslationWriter::disableBackup() to disable the backup.', E_USER_DEPRECATED);
                     copy($fullpath, $fullpath.'~');
                 }
             } else {

Tests/Dumper/FileDumperTest.php

@@ -29,6 +29,9 @@ public function testDump()
         $this->assertTrue(file_exists($tempDir.'/messages.en.concrete'));
     }
 
+    /**
+     * @group legacy
+     */
     public function testDumpBackupsFileIfExisting()
     {
         $tempDir = sys_get_temp_dir();