bug symfony#25438 [Yaml] empty lines don't count for indent detection (xabbuh)

This PR was merged into the 3.3 branch.

Discussion
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[Yaml] empty lines don't count for indent detection

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#25405
| License       | MIT
| Doc PR        |

Commits
-------

eb073fa empty lines don't count for indent detection

Author: fabpot

src/Symfony/Component/Yaml/Parser.php

@@ -543,8 +543,8 @@ private function getNextEmbedBlock($indentation = null, $inSequence = false)
             do {
                 $EOF = false;
 
-                // comment-like lines do not influence the indentation depth
-                if ($this->isCurrentLineComment()) {
+                // empty and comment-like lines do not influence the indentation depth
+                if ($this->isCurrentLineEmpty() || $this->isCurrentLineComment()) {
                     $EOF = !$this->moveToNextLine();
 
                     if (!$EOF) {
@@ -571,7 +571,7 @@ private function getNextEmbedBlock($indentation = null, $inSequence = false)
         $data = array();
         if ($this->getCurrentLineIndentation() >= $newIndent) {
             $data[] = substr($this->currentLine, $newIndent);
-        } elseif ($this->isCurrentLineComment()) {
+        } elseif ($this->isCurrentLineEmpty() || $this->isCurrentLineComment()) {
             $data[] = $this->currentLine;
         } else {
             $this->moveToPreviousLine();

src/Symfony/Component/Yaml/Tests/ParserTest.php

@@ -2073,6 +2073,18 @@ public function indentedMappingData()
         );
         $tests['mapping in sequence starting on a new line'] = array($yaml, $expected);
 
+        $yaml = <<<YAML
+foo:
+
+    bar: baz
+YAML;
+        $expected = array(
+            'foo' => array(
+                'bar' => 'baz',
+            ),
+        );
+        $tests['blank line at the beginning of an indented mapping value'] = array($yaml, $expected);
+
         return $tests;
     }
 }