Merge branch '4.3' into 4.4

* 4.3:
  cs fix
  Fix inconsistent return points.
  [Config] Add handling for ignored keys in ArrayNode::mergeValues.
  Fix inconsistent return points.
  [Security/Core] UserInterface::getPassword() can return null
  [Router] Fix TraceableUrlMatcher behaviour with trailing slash
  Revert "bug #33092 [DependencyInjection] Improve an exception message (fabpot)"

Author: nicolas-grekas

Command/LintCommand.php

@@ -199,10 +199,13 @@ private function getFiles(string $fileOrDirectory)
         }
     }
 
+    /**
+     * @return string|null
+     */
     private function getStdin()
     {
         if (0 !== ftell(STDIN)) {
-            return;
+            return null;
         }
 
         $inputs = '';

Inline.php

@@ -575,7 +575,7 @@ private static function evaluateScalar(string $scalar, int $flags, array $refere
             case 'null' === $scalarLower:
             case '' === $scalar:
             case '~' === $scalar:
-                return;
+                return null;
             case 'true' === $scalarLower:
                 return true;
             case 'false' === $scalarLower:
@@ -595,7 +595,7 @@ private static function evaluateScalar(string $scalar, int $flags, array $refere
                             throw new ParseException('Object support when parsing a YAML file has been disabled.', self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                         }
 
-                        return;
+                        return null;
                     case 0 === strpos($scalar, '!php/const'):
                         if (self::$constantSupport) {
                             $i = 0;
@@ -609,7 +609,7 @@ private static function evaluateScalar(string $scalar, int $flags, array $refere
                             throw new ParseException(sprintf('The string "%s" could not be parsed as a constant. Have you forgotten to pass the "Yaml::PARSE_CONSTANT" flag to the parser?', $scalar), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                         }
 
-                        return;
+                        return null;
                     case 0 === strpos($scalar, '!!float '):
                         return (float) substr($scalar, 8);
                     case 0 === strpos($scalar, '!!binary '):

Parser.php

@@ -512,12 +512,12 @@ private function getCurrentLineIndentation(): int
      *
      * @throws ParseException When indentation problem are detected
      */
-    private function getNextEmbedBlock(int $indentation = null, bool $inSequence = false): ?string
+    private function getNextEmbedBlock(int $indentation = null, bool $inSequence = false): string
     {
         $oldLineIndentation = $this->getCurrentLineIndentation();
 
         if (!$this->moveToNextLine()) {
-            return null;
+            return '';
         }
 
         if (null === $indentation) {
@@ -560,15 +560,15 @@ private function getNextEmbedBlock(int $indentation = null, bool $inSequence = f
         } else {
             $this->moveToPreviousLine();
 
-            return null;
+            return '';
         }
 
         if ($inSequence && $oldLineIndentation === $newIndent && isset($data[0][0]) && '-' === $data[0][0]) {
             // the previous line contained a dash but no item content, this line is a sequence item with the same indentation
             // and therefore no nested list or mapping
             $this->moveToPreviousLine();
 
-            return null;
+            return '';
         }
 
         $isItUnindentedCollection = $this->isStringUnIndentedCollectionItem();
@@ -739,8 +739,6 @@ private function parseValue(string $value, int $flags, string $context)
      * @param string $style       The style indicator that was used to begin this block scalar (| or >)
      * @param string $chomping    The chomping indicator that was used to begin this block scalar (+ or -)
      * @param int    $indentation The indentation indicator that was used to begin this block scalar
-     *
-     * @return string The text value
      */
     private function parseBlockScalar(string $style, string $chomping = '', int $indentation = 0): string
     {