From 6c2262203ee992c131dbb10c6a7f9f0a206c357a Mon Sep 17 00:00:00 2001
From: Zayan Goripov <15webgoripov@gmail.com>
Date: Sun, 5 Feb 2023 11:53:57 +0300
Subject: [PATCH] [Serializer] Fix CsvEncoder decode on empty data

---
 src/Symfony/Component/Serializer/Encoder/CsvEncoder.php   | 2 +-
 .../Component/Serializer/Tests/Encoder/CsvEncoderTest.php | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php b/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
index 4c518145612d2..55f78b1d0e013 100644
--- a/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
+++ b/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
@@ -167,7 +167,7 @@ public function decode(string $data, string $format, array $context = [])
                     $headerCount = array_fill(0, $nbCols, 1);
                 } else {
                     foreach ($cols as $col) {
-                        $header = explode($keySeparator, $col);
+                        $header = explode($keySeparator, $col ?? '');
                         $headers[] = $header;
                         $headerCount[] = \count($header);
                     }
diff --git a/src/Symfony/Component/Serializer/Tests/Encoder/CsvEncoderTest.php b/src/Symfony/Component/Serializer/Tests/Encoder/CsvEncoderTest.php
index 92df80ea98215..06cf6a0617d86 100644
--- a/src/Symfony/Component/Serializer/Tests/Encoder/CsvEncoderTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Encoder/CsvEncoderTest.php
@@ -211,6 +211,14 @@ public function testEncodeEmptyArray()
     {
         $this->assertEquals("\n\n", $this->encoder->encode([], 'csv'));
         $this->assertEquals("\n\n", $this->encoder->encode([[]], 'csv'));
+        $this->assertEquals("\n\n", $this->encoder->encode([['' => null]], 'csv'));
+    }
+
+    public function testDecodeEmptyData()
+    {
+        $data = $this->encoder->decode("\n\n", 'csv');
+
+        $this->assertSame([['' => null]], $data);
     }
 
     public function testEncodeVariableStructure()