Merge branch '3.0'

* 3.0:
  #17676 - making the proxy instantiation compatible with ProxyManager 2.x by detecting proxy features
  #17676 - making the proxy instantiation compatible with ProxyManager 2.x by detecting proxy features
  Fix bug when using an private aliased factory service
  [Form] fix tests added by #17798 by removing `choices_as_values`
  [Form] fix FQCN in tests added by #17798
  [DependencyInjection] Remove unused parameter of private property
  bug #17798 [Form] allow `choice_label` option to be `false`
  [Form] fix tests added by #17760 with FQCN
  ChoiceFormField of type "select" could be "disabled"
  Update contributing docs
  [Console] Fix escaping of trailing backslashes
  Fix constraint validator alias being required
  [DependencyInjection] Simplified code in AutowirePass
  [ci] clone with depth=1 to kill push-forced PRs
  Add check on If-Range header

Formatter/OutputFormatter.php

@@ -33,7 +33,15 @@ class OutputFormatter implements OutputFormatterInterface
      */
     public static function escape($text)
     {
-        return preg_replace('/([^\\\\]?)</', '$1\\<', $text);
+        $text = preg_replace('/([^\\\\]?)</', '$1\\<', $text);
+
+        if ('\\' === substr($text, -1)) {
+            $len = strlen($text);
+            $text = rtrim($text, '\\');
+            $text .= str_repeat('<<', $len - strlen($text));
+        }
+
+        return $text;
     }
 
     /**
@@ -131,7 +139,7 @@ public function format($message)
         $message = (string) $message;
         $offset = 0;
         $output = '';
-        $tagRegex = '[a-z][a-z0-9_=;-]*';
+        $tagRegex = '[a-z][a-z0-9_=;-]*+';
         preg_match_all("#<(($tagRegex) | /($tagRegex)?)>#ix", $message, $matches, PREG_OFFSET_CAPTURE);
         foreach ($matches[0] as $i => $match) {
             $pos = $match[1];
@@ -166,6 +174,10 @@ public function format($message)
 
         $output .= $this->applyCurrentStyle(substr($message, $offset));
 
+        if (false !== strpos($output, '<<')) {
+            return strtr($output, array('\\<' => '<', '<<' => '\\'));
+        }
+
         return str_replace('\\<', '<', $output);
     }
 

Tests/Formatter/OutputFormatterTest.php

@@ -98,8 +98,8 @@ public function testStyleEscaping()
         $formatter = new OutputFormatter(true);
 
         $this->assertEquals(
-            "(\033[32mz>=2.0,<a2.3\033[39m)",
-            $formatter->format('(<info>'.$formatter->escape('z>=2.0,<a2.3').'</info>)')
+            "(\033[32mz>=2.0,<<<a2.3\\\033[39m)",
+            $formatter->format('(<info>'.$formatter->escape('z>=2.0,<\\<<a2.3\\').'</info>)')
         );
 
         $this->assertEquals(