From 31b0472331c4e87fff70628fbcef96f2d99a4c3f Mon Sep 17 00:00:00 2001
From: Roman Martinuk <romanmartinuk@gmail.com>
Date: Wed, 17 Mar 2021 18:58:33 +0300
Subject: [PATCH] fixed parser

---
 src/Symfony/Component/Yaml/Parser.php         | 12 ++++++-
 .../Yaml/Tests/Fixtures/YtsBasicTests.yml     | 34 +++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/src/Symfony/Component/Yaml/Parser.php b/src/Symfony/Component/Yaml/Parser.php
index 6d0d523265348..f26b90f1b00b0 100644
--- a/src/Symfony/Component/Yaml/Parser.php
+++ b/src/Symfony/Component/Yaml/Parser.php
@@ -169,7 +169,16 @@ private function doParse(string $value, int $flags)
                 }
 
                 // array
-                if (!isset($values['value']) || '' == trim($values['value'], ' ') || 0 === strpos(ltrim($values['value'], ' '), '#')) {
+                if (isset($values['value']) && 0 === strpos(ltrim($values['value'], ' '), '-')) {
+                    // Inline first child
+                    $currentLineNumber = $this->getRealCurrentLineNb();
+
+                    $sequenceIndentation = \strlen($values['leadspaces']) + 1;
+                    $sequenceYaml = substr($this->currentLine, $sequenceIndentation);
+                    $sequenceYaml .= "\n".$this->getNextEmbedBlock($sequenceIndentation, true);
+
+                    $data[] = $this->parseBlock($currentLineNumber, rtrim($sequenceYaml), $flags);
+                } elseif (!isset($values['value']) || '' == trim($values['value'], ' ') || 0 === strpos(ltrim($values['value'], ' '), '#')) {
                     $data[] = $this->parseBlock($this->getRealCurrentLineNb() + 1, $this->getNextEmbedBlock(null, true) ?? '', $flags);
                 } elseif (null !== $subTag = $this->getLineTag(ltrim($values['value'], ' '), $flags)) {
                     $data[] = new TaggedValue(
@@ -604,6 +613,7 @@ private function getNextEmbedBlock(int $indentation = null, bool $inSequence = f
         }
 
         $data = [];
+
         if ($this->getCurrentLineIndentation() >= $newIndent) {
             $data[] = substr($this->currentLine, $newIndent);
         } elseif ($this->isCurrentLineEmpty() || $this->isCurrentLineComment()) {
diff --git a/src/Symfony/Component/Yaml/Tests/Fixtures/YtsBasicTests.yml b/src/Symfony/Component/Yaml/Tests/Fixtures/YtsBasicTests.yml
index 1a08d8ea9fddf..621e224490da8 100644
--- a/src/Symfony/Component/Yaml/Tests/Fixtures/YtsBasicTests.yml
+++ b/src/Symfony/Component/Yaml/Tests/Fixtures/YtsBasicTests.yml
@@ -200,3 +200,37 @@ php: |
          'age' => 38
        ]
      ]
+---
+test: Inline first element in sequence blocks 1
+yaml: |
+  - - s1_i1
+    - s1_i2
+  - s2
+php: |
+  [
+    [
+      "s1_i1",
+      "s1_i2"
+    ],
+    "s2"
+  ]
+---
+test: Inline first element in sequence blocks 2
+yaml: |
+  - - s1_i1
+    - - s1_i1_1
+      - s1_i1_2
+    - s1_i2
+  - s2
+php: |
+  [
+    [
+      "s1_i1",
+      [
+        "s1_i1_1",
+        "s1_i1_2",
+      ],
+      "s1_i2"
+    ],
+    "s2"
+  ]