Upgrade 1-11.38

vendor/symfony/serializer/Encoder/ChainDecoder.php

@@ -20,9 +20,9 @@ use Symfony\Component\Serializer\Exception\RuntimeException;
  * @author Johannes M. Schmitt <schmittjoh@gmail.com>
  * @author Lukas Kahwe Smith <smith@pooteeweet.org>
  *
- * @final since version 3.3.
+ * @final
  */
-class ChainDecoder implements DecoderInterface /*, ContextAwareDecoderInterface*/
+class ChainDecoder implements ContextAwareDecoderInterface
 {
     protected $decoders = [];
     protected $decoderByFormat = [];
@@ -43,10 +43,8 @@ class ChainDecoder implements DecoderInterface /*, ContextAwareDecoderInterface*
     /**
      * {@inheritdoc}
      */
-    public function supportsDecoding($format/*, array $context = []*/)
+    public function supportsDecoding($format, array $context = []): bool
     {
-        $context = \func_num_args() > 1 ? func_get_arg(1) : [];
-
         try {
             $this->getDecoder($format, $context);
         } catch (RuntimeException $e) {
@@ -59,13 +57,9 @@ class ChainDecoder implements DecoderInterface /*, ContextAwareDecoderInterface*
     /**
      * Gets the decoder supporting the format.
      *
-     * @param string $format
-     *
-     * @return DecoderInterface
-     *
      * @throws RuntimeException if no decoder is found
      */
-    private function getDecoder($format, array $context)
+    private function getDecoder(string $format, array $context): DecoderInterface
     {
         if (isset($this->decoderByFormat[$format])
             && isset($this->decoders[$this->decoderByFormat[$format]])
@@ -73,9 +67,13 @@ class ChainDecoder implements DecoderInterface /*, ContextAwareDecoderInterface*
             return $this->decoders[$this->decoderByFormat[$format]];
         }
 
+        $cache = true;
         foreach ($this->decoders as $i => $decoder) {
+            $cache = $cache && !$decoder instanceof ContextAwareDecoderInterface;
             if ($decoder->supportsDecoding($format, $context)) {
-                $this->decoderByFormat[$format] = $i;
+                if ($cache) {
+                    $this->decoderByFormat[$format] = $i;
+                }
 
                 return $decoder;
             }

vendor/symfony/serializer/Encoder/ChainEncoder.php

@@ -20,9 +20,9 @@ use Symfony\Component\Serializer\Exception\RuntimeException;
  * @author Johannes M. Schmitt <schmittjoh@gmail.com>
  * @author Lukas Kahwe Smith <smith@pooteeweet.org>
  *
- * @final since version 3.3.
+ * @final
  */
-class ChainEncoder implements EncoderInterface /*, ContextAwareEncoderInterface*/
+class ChainEncoder implements ContextAwareEncoderInterface
 {
     protected $encoders = [];
     protected $encoderByFormat = [];
@@ -43,10 +43,8 @@ class ChainEncoder implements EncoderInterface /*, ContextAwareEncoderInterface*
     /**
      * {@inheritdoc}
      */
-    public function supportsEncoding($format/*, array $context = []*/)
+    public function supportsEncoding($format, array $context = []): bool
     {
-        $context = \func_num_args() > 1 ? func_get_arg(1) : [];
-
         try {
             $this->getEncoder($format, $context);
         } catch (RuntimeException $e) {
@@ -58,14 +56,9 @@ class ChainEncoder implements EncoderInterface /*, ContextAwareEncoderInterface*
 
     /**
      * Checks whether the normalization is needed for the given format.
-     *
-     * @param string $format
-     *
-     * @return bool
      */
-    public function needsNormalization($format/*, array $context = []*/)
+    public function needsNormalization(string $format, array $context = []): bool
     {
-        $context = \func_num_args() > 1 ? func_get_arg(1) : [];
         $encoder = $this->getEncoder($format, $context);
 
         if (!$encoder instanceof NormalizationAwareInterface) {
@@ -82,13 +75,9 @@ class ChainEncoder implements EncoderInterface /*, ContextAwareEncoderInterface*
     /**
      * Gets the encoder supporting the format.
      *
-     * @param string $format
-     *
-     * @return EncoderInterface
-     *
      * @throws RuntimeException if no encoder is found
      */
-    private function getEncoder($format, array $context)
+    private function getEncoder(string $format, array $context): EncoderInterface
     {
         if (isset($this->encoderByFormat[$format])
             && isset($this->encoders[$this->encoderByFormat[$format]])
@@ -96,9 +85,13 @@ class ChainEncoder implements EncoderInterface /*, ContextAwareEncoderInterface*
             return $this->encoders[$this->encoderByFormat[$format]];
         }
 
+        $cache = true;
         foreach ($this->encoders as $i => $encoder) {
+            $cache = $cache && !$encoder instanceof ContextAwareEncoderInterface;
             if ($encoder->supportsEncoding($format, $context)) {
-                $this->encoderByFormat[$format] = $i;
+                if ($cache) {
+                    $this->encoderByFormat[$format] = $i;
+                }
 
                 return $encoder;
             }

vendor/symfony/serializer/Encoder/CsvEncoder.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Serializer\Encoder;
 
 use Symfony\Component\Serializer\Exception\InvalidArgumentException;
+use Symfony\Component\Serializer\Exception\UnexpectedValueException;
 
 /**
  * Encodes CSV data.
@@ -21,34 +22,55 @@ use Symfony\Component\Serializer\Exception\InvalidArgumentException;
  */
 class CsvEncoder implements EncoderInterface, DecoderInterface
 {
-    const FORMAT = 'csv';
-    const DELIMITER_KEY = 'csv_delimiter';
-    const ENCLOSURE_KEY = 'csv_enclosure';
-    const ESCAPE_CHAR_KEY = 'csv_escape_char';
-    const KEY_SEPARATOR_KEY = 'csv_key_separator';
-    const HEADERS_KEY = 'csv_headers';
+    public const FORMAT = 'csv';
+    public const DELIMITER_KEY = 'csv_delimiter';
+    public const ENCLOSURE_KEY = 'csv_enclosure';
+    public const ESCAPE_CHAR_KEY = 'csv_escape_char';
+    public const KEY_SEPARATOR_KEY = 'csv_key_separator';
+    public const HEADERS_KEY = 'csv_headers';
+    public const ESCAPE_FORMULAS_KEY = 'csv_escape_formulas';
+    public const AS_COLLECTION_KEY = 'as_collection';
+    public const NO_HEADERS_KEY = 'no_headers';
+    public const OUTPUT_UTF8_BOM_KEY = 'output_utf8_bom';
 
-    private $delimiter;
-    private $enclosure;
-    private $escapeChar;
-    private $keySeparator;
+    private const UTF8_BOM = "\xEF\xBB\xBF";
+
+    private const FORMULAS_START_CHARACTERS = ['=', '-', '+', '@', "\t", "\r"];
+
+    private $defaultContext = [
+        self::DELIMITER_KEY => ',',
+        self::ENCLOSURE_KEY => '"',
+        self::ESCAPE_CHAR_KEY => '',
+        self::ESCAPE_FORMULAS_KEY => false,
+        self::HEADERS_KEY => [],
+        self::KEY_SEPARATOR_KEY => '.',
+        self::NO_HEADERS_KEY => false,
+        self::AS_COLLECTION_KEY => false,
+        self::OUTPUT_UTF8_BOM_KEY => false,
+    ];
 
     /**
-     * @param string $delimiter
-     * @param string $enclosure
-     * @param string $escapeChar
-     * @param string $keySeparator
+     * @param array $defaultContext
      */
-    public function __construct($delimiter = ',', $enclosure = '"', $escapeChar = '', $keySeparator = '.')
+    public function __construct($defaultContext = [], string $enclosure = '"', string $escapeChar = '', string $keySeparator = '.', bool $escapeFormulas = false)
     {
-        if ('' === $escapeChar && \PHP_VERSION_ID < 70400) {
-            $escapeChar = '\\';
+        if (!\is_array($defaultContext)) {
+            @trigger_error('Passing configuration options directly to the constructor is deprecated since Symfony 4.2, use the default context instead.', \E_USER_DEPRECATED);
+
+            $defaultContext = [
+                self::DELIMITER_KEY => (string) $defaultContext,
+                self::ENCLOSURE_KEY => $enclosure,
+                self::ESCAPE_CHAR_KEY => $escapeChar,
+                self::KEY_SEPARATOR_KEY => $keySeparator,
+                self::ESCAPE_FORMULAS_KEY => $escapeFormulas,
+            ];
         }
 
-        $this->delimiter = $delimiter;
-        $this->enclosure = $enclosure;
-        $this->escapeChar = $escapeChar;
-        $this->keySeparator = $keySeparator;
+        $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
+
+        if (\PHP_VERSION_ID < 70400 && '' === $this->defaultContext[self::ESCAPE_CHAR_KEY]) {
+            $this->defaultContext[self::ESCAPE_CHAR_KEY] = '\\';
+        }
     }
 
     /**
@@ -58,7 +80,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
     {
         $handle = fopen('php://temp,', 'w+');
 
-        if (!\is_array($data)) {
+        if (!is_iterable($data)) {
             $data = [[$data]];
         } elseif (empty($data)) {
             $data = [[]];
@@ -75,18 +97,20 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
             }
         }
 
-        list($delimiter, $enclosure, $escapeChar, $keySeparator, $headers) = $this->getCsvOptions($context);
+        [$delimiter, $enclosure, $escapeChar, $keySeparator, $headers, $escapeFormulas, $outputBom] = $this->getCsvOptions($context);
 
         foreach ($data as &$value) {
             $flattened = [];
-            $this->flatten($value, $flattened, $keySeparator);
+            $this->flatten($value, $flattened, $keySeparator, '', $escapeFormulas);
             $value = $flattened;
         }
         unset($value);
 
         $headers = array_merge(array_values($headers), array_diff($this->extractHeaders($data), $headers));
 
-        fputcsv($handle, $headers, $delimiter, $enclosure, $escapeChar);
+        if (!($context[self::NO_HEADERS_KEY] ?? $this->defaultContext[self::NO_HEADERS_KEY])) {
+            fputcsv($handle, $headers, $delimiter, $enclosure, $escapeChar);
+        }
 
         $headers = array_fill_keys($headers, '');
         foreach ($data as $row) {
@@ -97,6 +121,14 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
         $value = stream_get_contents($handle);
         fclose($handle);
 
+        if ($outputBom) {
+            if (!preg_match('//u', $value)) {
+                throw new UnexpectedValueException('You are trying to add a UTF-8 BOM to a non UTF-8 text.');
+            }
+
+            $value = self::UTF8_BOM.$value;
+        }
+
         return $value;
     }
 
@@ -117,12 +149,16 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
         fwrite($handle, $data);
         rewind($handle);
 
+        if (str_starts_with($data, self::UTF8_BOM)) {
+            fseek($handle, \strlen(self::UTF8_BOM));
+        }
+
         $headers = null;
         $nbHeaders = 0;
         $headerCount = [];
         $result = [];
 
-        list($delimiter, $enclosure, $escapeChar, $keySeparator) = $this->getCsvOptions($context);
+        [$delimiter, $enclosure, $escapeChar, $keySeparator] = $this->getCsvOptions($context);
 
         while (false !== ($cols = fgetcsv($handle, 0, $delimiter, $enclosure, $escapeChar))) {
             $nbCols = \count($cols);
@@ -130,13 +166,20 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
             if (null === $headers) {
                 $nbHeaders = $nbCols;
 
-                foreach ($cols as $col) {
-                    $header = explode($keySeparator, $col);
-                    $headers[] = $header;
-                    $headerCount[] = \count($header);
-                }
+                if ($context[self::NO_HEADERS_KEY] ?? $this->defaultContext[self::NO_HEADERS_KEY]) {
+                    for ($i = 0; $i < $nbCols; ++$i) {
+                        $headers[] = [$i];
+                    }
+                    $headerCount = array_fill(0, $nbCols, 1);
+                } else {
+                    foreach ($cols as $col) {
+                        $header = explode($keySeparator, $col);
+                        $headers[] = $header;
+                        $headerCount[] = \count($header);
+                    }
 
-                continue;
+                    continue;
+                }
             }
 
             $item = [];
@@ -163,10 +206,18 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
         }
         fclose($handle);
 
+        if ($context[self::AS_COLLECTION_KEY] ?? $this->defaultContext[self::AS_COLLECTION_KEY]) {
+            return $result;
+        }
+
         if (empty($result) || isset($result[1])) {
             return $result;
         }
 
+        if (!isset($context['as_collection'])) {
+            @trigger_error('Relying on the default value (false) of the "as_collection" option is deprecated since 4.2. You should set it to false explicitly instead as true will be the default value in 5.0.', \E_USER_DEPRECATED);
+        }
+
         // If there is only one data line in the document, return it (the line), the result is not considered as a collection
         return $result[0];
     }
@@ -181,41 +232,44 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
 
     /**
      * Flattens an array and generates keys including the path.
-     *
-     * @param string $keySeparator
-     * @param string $parentKey
      */
-    private function flatten(array $array, array &$result, $keySeparator, $parentKey = '')
+    private function flatten(iterable $array, array &$result, string $keySeparator, string $parentKey = '', bool $escapeFormulas = false)
     {
         foreach ($array as $key => $value) {
-            if (\is_array($value)) {
-                $this->flatten($value, $result, $keySeparator, $parentKey.$key.$keySeparator);
+            if (is_iterable($value)) {
+                $this->flatten($value, $result, $keySeparator, $parentKey.$key.$keySeparator, $escapeFormulas);
             } else {
-                // Ensures an actual value is used when dealing with true and false
-                $result[$parentKey.$key] = false === $value ? 0 : (true === $value ? 1 : $value);
+                if ($escapeFormulas && \in_array(substr((string) $value, 0, 1), self::FORMULAS_START_CHARACTERS, true)) {
+                    $result[$parentKey.$key] = "'".$value;
+                } else {
+                    // Ensures an actual value is used when dealing with true and false
+                    $result[$parentKey.$key] = false === $value ? 0 : (true === $value ? 1 : $value);
+                }
             }
         }
     }
 
-    private function getCsvOptions(array $context)
+    private function getCsvOptions(array $context): array
     {
-        $delimiter = isset($context[self::DELIMITER_KEY]) ? $context[self::DELIMITER_KEY] : $this->delimiter;
-        $enclosure = isset($context[self::ENCLOSURE_KEY]) ? $context[self::ENCLOSURE_KEY] : $this->enclosure;
-        $escapeChar = isset($context[self::ESCAPE_CHAR_KEY]) ? $context[self::ESCAPE_CHAR_KEY] : $this->escapeChar;
-        $keySeparator = isset($context[self::KEY_SEPARATOR_KEY]) ? $context[self::KEY_SEPARATOR_KEY] : $this->keySeparator;
-        $headers = isset($context[self::HEADERS_KEY]) ? $context[self::HEADERS_KEY] : [];
+        $delimiter = $context[self::DELIMITER_KEY] ?? $this->defaultContext[self::DELIMITER_KEY];
+        $enclosure = $context[self::ENCLOSURE_KEY] ?? $this->defaultContext[self::ENCLOSURE_KEY];
+        $escapeChar = $context[self::ESCAPE_CHAR_KEY] ?? $this->defaultContext[self::ESCAPE_CHAR_KEY];
+        $keySeparator = $context[self::KEY_SEPARATOR_KEY] ?? $this->defaultContext[self::KEY_SEPARATOR_KEY];
+        $headers = $context[self::HEADERS_KEY] ?? $this->defaultContext[self::HEADERS_KEY];
+        $escapeFormulas = $context[self::ESCAPE_FORMULAS_KEY] ?? $this->defaultContext[self::ESCAPE_FORMULAS_KEY];
+        $outputBom = $context[self::OUTPUT_UTF8_BOM_KEY] ?? $this->defaultContext[self::OUTPUT_UTF8_BOM_KEY];
 
         if (!\is_array($headers)) {
             throw new InvalidArgumentException(sprintf('The "%s" context variable must be an array or null, given "%s".', self::HEADERS_KEY, \gettype($headers)));
         }
 
-        return [$delimiter, $enclosure, $escapeChar, $keySeparator, $headers];
+        return [$delimiter, $enclosure, $escapeChar, $keySeparator, $headers, $escapeFormulas, $outputBom];
     }
 
     /**
      * @return string[]
      */
-    private function extractHeaders(array $data)
+    private function extractHeaders(iterable $data): array
     {
         $headers = [];
         $flippedHeaders = [];

vendor/symfony/serializer/Encoder/EncoderInterface.php

@@ -25,7 +25,7 @@ interface EncoderInterface
      * @param string $format  Format name
      * @param array  $context Options that normalizers/encoders have access to
      *
-     * @return string|int|float|bool
+     * @return string
      *
      * @throws UnexpectedValueException
      */

vendor/symfony/serializer/Encoder/JsonDecode.php

@@ -22,19 +22,41 @@ class JsonDecode implements DecoderInterface
 {
     protected $serializer;
 
-    private $associative;
-    private $recursionDepth;
+    /**
+     * True to return the result as an associative array, false for a nested stdClass hierarchy.
+     */
+    public const ASSOCIATIVE = 'json_decode_associative';
+
+    public const OPTIONS = 'json_decode_options';
+
+    /**
+     * Specifies the recursion depth.
+     */
+    public const RECURSION_DEPTH = 'json_decode_recursion_depth';
+
+    private $defaultContext = [
+        self::ASSOCIATIVE => false,
+        self::OPTIONS => 0,
+        self::RECURSION_DEPTH => 512,
+    ];
 
     /**
      * Constructs a new JsonDecode instance.
      *
-     * @param bool $associative True to return the result associative array, false for a nested stdClass hierarchy
-     * @param int  $depth       Specifies the recursion depth
+     * @param array $defaultContext
      */
-    public function __construct($associative = false, $depth = 512)
+    public function __construct($defaultContext = [], int $depth = 512)
     {
-        $this->associative = $associative;
-        $this->recursionDepth = (int) $depth;
+        if (!\is_array($defaultContext)) {
+            @trigger_error(sprintf('Using constructor parameters that are not a default context is deprecated since Symfony 4.2, use the "%s" and "%s" keys of the context instead.', self::ASSOCIATIVE, self::RECURSION_DEPTH), \E_USER_DEPRECATED);
+
+            $defaultContext = [
+                self::ASSOCIATIVE => (bool) $defaultContext,
+                self::RECURSION_DEPTH => $depth,
+            ];
+        }
+
+        $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
     }
 
     /**
@@ -47,7 +69,7 @@ class JsonDecode implements DecoderInterface
      * The $context array is a simple key=>value array, with the following supported keys:
      *
      * json_decode_associative: boolean
-     *      If true, returns the object as associative array.
+     *      If true, returns the object as an associative array.
      *      If false, returns the object as nested stdClass
      *      If not specified, this method will use the default set in JsonDecode::__construct
      *
@@ -56,7 +78,7 @@ class JsonDecode implements DecoderInterface
      *      If not specified, this method will use the default set in JsonDecode::__construct
      *
      * json_decode_options: integer
-     *      Specifies additional options as per documentation for json_decode. Only supported with PHP 5.4.0 and higher
+     *      Specifies additional options as per documentation for json_decode
      *
      * @return mixed
      *
@@ -66,11 +88,9 @@ class JsonDecode implements DecoderInterface
      */
     public function decode($data, $format, array $context = [])
     {
-        $context = $this->resolveContext($context);
-
-        $associative = $context['json_decode_associative'];
-        $recursionDepth = $context['json_decode_recursion_depth'];
-        $options = $context['json_decode_options'];
+        $associative = $context[self::ASSOCIATIVE] ?? $this->defaultContext[self::ASSOCIATIVE];
+        $recursionDepth = $context[self::RECURSION_DEPTH] ?? $this->defaultContext[self::RECURSION_DEPTH];
+        $options = $context[self::OPTIONS] ?? $this->defaultContext[self::OPTIONS];
 
         try {
             $decodedData = json_decode($data, $associative, $recursionDepth, $options);
@@ -96,20 +116,4 @@ class JsonDecode implements DecoderInterface
     {
         return JsonEncoder::FORMAT === $format;
     }
-
-    /**
-     * Merges the default options of the Json Decoder with the passed context.
-     *
-     * @return array
-     */
-    private function resolveContext(array $context)
-    {
-        $defaultOptions = [
-            'json_decode_associative' => $this->associative,
-            'json_decode_recursion_depth' => $this->recursionDepth,
-            'json_decode_options' => 0,
-        ];
-
-        return array_merge($defaultOptions, $context);
-    }
 }

vendor/symfony/serializer/Encoder/JsonEncode.php

@@ -20,11 +20,24 @@ use Symfony\Component\Serializer\Exception\NotEncodableValueException;
  */
 class JsonEncode implements EncoderInterface
 {
-    private $options;
+    public const OPTIONS = 'json_encode_options';
 
-    public function __construct($bitmask = 0)
+    private $defaultContext = [
+        self::OPTIONS => 0,
+    ];
+
+    /**
+     * @param array $defaultContext
+     */
+    public function __construct($defaultContext = [])
     {
-        $this->options = $bitmask;
+        if (!\is_array($defaultContext)) {
+            @trigger_error(sprintf('Passing an integer as first parameter of the "%s()" method is deprecated since Symfony 4.2, use the "json_encode_options" key of the context instead.', __METHOD__), \E_USER_DEPRECATED);
+
+            $this->defaultContext[self::OPTIONS] = (int) $defaultContext;
+        } else {
+            $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
+        }
     }
 
     /**
@@ -34,8 +47,7 @@ class JsonEncode implements EncoderInterface
      */
     public function encode($data, $format, array $context = [])
     {
-        $context = $this->resolveContext($context);
-        $options = $context['json_encode_options'];
+        $options = $context[self::OPTIONS] ?? $this->defaultContext[self::OPTIONS];
 
         try {
             $encodedJson = json_encode($data, $options);
@@ -61,14 +73,4 @@ class JsonEncode implements EncoderInterface
     {
         return JsonEncoder::FORMAT === $format;
     }
-
-    /**
-     * Merge default json encode options with context.
-     *
-     * @return array
-     */
-    private function resolveContext(array $context = [])
-    {
-        return array_merge(['json_encode_options' => $this->options], $context);
-    }
 }

vendor/symfony/serializer/Encoder/JsonEncoder.php

@@ -18,15 +18,15 @@ namespace Symfony\Component\Serializer\Encoder;
  */
 class JsonEncoder implements EncoderInterface, DecoderInterface
 {
-    const FORMAT = 'json';
+    public const FORMAT = 'json';
 
     protected $encodingImpl;
     protected $decodingImpl;
 
     public function __construct(JsonEncode $encodingImpl = null, JsonDecode $decodingImpl = null)
     {
-        $this->encodingImpl = $encodingImpl ?: new JsonEncode();
-        $this->decodingImpl = $decodingImpl ?: new JsonDecode(true);
+        $this->encodingImpl = $encodingImpl ?? new JsonEncode();
+        $this->decodingImpl = $decodingImpl ?? new JsonDecode([JsonDecode::ASSOCIATIVE => true]);
     }
 
     /**

vendor/symfony/serializer/Encoder/SerializerAwareEncoder.php

@@ -1,27 +0,0 @@
-<?php
-
-/*
- * This file is part of the Symfony package.
- *
- * (c) Fabien Potencier <fabien@symfony.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-namespace Symfony\Component\Serializer\Encoder;
-
-use Symfony\Component\Serializer\SerializerAwareInterface;
-use Symfony\Component\Serializer\SerializerAwareTrait;
-
-/**
- * SerializerAware Encoder implementation.
- *
- * @author Jordi Boggiano <j.boggiano@seld.be>
- *
- * @deprecated since version 3.2, to be removed in 4.0. Use the SerializerAwareTrait instead.
- */
-abstract class SerializerAwareEncoder implements SerializerAwareInterface
-{
-    use SerializerAwareTrait;
-}

vendor/symfony/serializer/Encoder/XmlEncoder.php

@@ -13,38 +13,76 @@ namespace Symfony\Component\Serializer\Encoder;
 
 use Symfony\Component\Serializer\Exception\BadMethodCallException;
 use Symfony\Component\Serializer\Exception\NotEncodableValueException;
+use Symfony\Component\Serializer\SerializerAwareInterface;
+use Symfony\Component\Serializer\SerializerAwareTrait;
 
 /**
- * Encodes XML data.
- *
  * @author Jordi Boggiano <j.boggiano@seld.be>
  * @author John Wards <jwards@whiteoctober.co.uk>
  * @author Fabian Vogler <fabian@equivalence.ch>
  * @author Kévin Dunglas <dunglas@gmail.com>
+ * @author Dany Maillard <danymaillard93b@gmail.com>
  */
-class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, DecoderInterface, NormalizationAwareInterface
+class XmlEncoder implements EncoderInterface, DecoderInterface, NormalizationAwareInterface, SerializerAwareInterface
 {
-    const FORMAT = 'xml';
+    use SerializerAwareTrait;
+
+    public const FORMAT = 'xml';
+
+    public const AS_COLLECTION = 'as_collection';
 
     /**
-     * @var \DOMDocument
+     * An array of ignored XML node types while decoding, each one of the DOM Predefined XML_* constants.
      */
-    private $dom;
-    private $format;
-    private $context;
-    private $rootNodeName = 'response';
-    private $loadOptions;
+    public const DECODER_IGNORED_NODE_TYPES = 'decoder_ignored_node_types';
 
     /**
-     * Construct new XmlEncoder and allow to change the root node element name.
-     *
-     * @param string   $rootNodeName
-     * @param int|null $loadOptions  A bit field of LIBXML_* constants
+     * An array of ignored XML node types while encoding, each one of the DOM Predefined XML_* constants.
      */
-    public function __construct($rootNodeName = 'response', $loadOptions = null)
+    public const ENCODER_IGNORED_NODE_TYPES = 'encoder_ignored_node_types';
+    public const ENCODING = 'xml_encoding';
+    public const FORMAT_OUTPUT = 'xml_format_output';
+
+    /**
+     * A bit field of LIBXML_* constants.
+     */
+    public const LOAD_OPTIONS = 'load_options';
+    public const REMOVE_EMPTY_TAGS = 'remove_empty_tags';
+    public const ROOT_NODE_NAME = 'xml_root_node_name';
+    public const STANDALONE = 'xml_standalone';
+
+    /** @deprecated The constant TYPE_CASE_ATTRIBUTES is deprecated since version 4.4 and will be removed in version 5. Use TYPE_CAST_ATTRIBUTES instead. */
+    public const TYPE_CASE_ATTRIBUTES = 'xml_type_cast_attributes';
+    public const TYPE_CAST_ATTRIBUTES = 'xml_type_cast_attributes';
+    public const VERSION = 'xml_version';
+
+    private $defaultContext = [
+        self::AS_COLLECTION => false,
+        self::DECODER_IGNORED_NODE_TYPES => [\XML_PI_NODE, \XML_COMMENT_NODE],
+        self::ENCODER_IGNORED_NODE_TYPES => [],
+        self::LOAD_OPTIONS => \LIBXML_NONET | \LIBXML_NOBLANKS,
+        self::REMOVE_EMPTY_TAGS => false,
+        self::ROOT_NODE_NAME => 'response',
+        self::TYPE_CAST_ATTRIBUTES => true,
+    ];
+
+    /**
+     * @param array $defaultContext
+     */
+    public function __construct($defaultContext = [], int $loadOptions = null, array $decoderIgnoredNodeTypes = [\XML_PI_NODE, \XML_COMMENT_NODE], array $encoderIgnoredNodeTypes = [])
     {
-        $this->rootNodeName = $rootNodeName;
-        $this->loadOptions = null !== $loadOptions ? $loadOptions : \LIBXML_NONET | \LIBXML_NOBLANKS;
+        if (!\is_array($defaultContext)) {
+            @trigger_error('Passing configuration options directly to the constructor is deprecated since Symfony 4.2, use the default context instead.', \E_USER_DEPRECATED);
+
+            $defaultContext = [
+                self::DECODER_IGNORED_NODE_TYPES => $decoderIgnoredNodeTypes,
+                self::ENCODER_IGNORED_NODE_TYPES => $encoderIgnoredNodeTypes,
+                self::LOAD_OPTIONS => $loadOptions ?? \LIBXML_NONET | \LIBXML_NOBLANKS,
+                self::ROOT_NODE_NAME => (string) $defaultContext,
+            ];
+        }
+
+        $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
     }
 
     /**
@@ -52,25 +90,25 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
      */
     public function encode($data, $format, array $context = [])
     {
+        $encoderIgnoredNodeTypes = $context[self::ENCODER_IGNORED_NODE_TYPES] ?? $this->defaultContext[self::ENCODER_IGNORED_NODE_TYPES];
+        $ignorePiNode = \in_array(\XML_PI_NODE, $encoderIgnoredNodeTypes, true);
         if ($data instanceof \DOMDocument) {
-            return $data->saveXML();
+            return $data->saveXML($ignorePiNode ? $data->documentElement : null);
         }
 
-        $xmlRootNodeName = $this->resolveXmlRootName($context);
+        $xmlRootNodeName = $context[self::ROOT_NODE_NAME] ?? $this->defaultContext[self::ROOT_NODE_NAME];
 
-        $this->dom = $this->createDomDocument($context);
-        $this->format = $format;
-        $this->context = $context;
+        $dom = $this->createDomDocument($context);
 
-        if (null !== $data && !is_scalar($data)) {
-            $root = $this->dom->createElement($xmlRootNodeName);
-            $this->dom->appendChild($root);
-            $this->buildXml($root, $data, $xmlRootNodeName);
+        if (null !== $data && !\is_scalar($data)) {
+            $root = $dom->createElement($xmlRootNodeName);
+            $dom->appendChild($root);
+            $this->buildXml($root, $data, $format, $context, $xmlRootNodeName);
         } else {
-            $this->appendNode($this->dom, $data, $xmlRootNodeName);
+            $this->appendNode($dom, $data, $format, $context, $xmlRootNodeName);
         }
 
-        return $this->dom->saveXML();
+        return $dom->saveXML($ignorePiNode ? $dom->documentElement : null);
     }
 
     /**
@@ -89,7 +127,7 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         libxml_clear_errors();
 
         $dom = new \DOMDocument();
-        $dom->loadXML($data, $this->loadOptions);
+        $dom->loadXML($data, $context[self::LOAD_OPTIONS] ?? $this->defaultContext[self::LOAD_OPTIONS]);
 
         libxml_use_internal_errors($internalErrors);
         if (\LIBXML_VERSION < 20900) {
@@ -103,11 +141,15 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         }
 
         $rootNode = null;
+        $decoderIgnoredNodeTypes = $context[self::DECODER_IGNORED_NODE_TYPES] ?? $this->defaultContext[self::DECODER_IGNORED_NODE_TYPES];
         foreach ($dom->childNodes as $child) {
+            if (\in_array($child->nodeType, $decoderIgnoredNodeTypes, true)) {
+                continue;
+            }
             if (\XML_DOCUMENT_TYPE_NODE === $child->nodeType) {
                 throw new NotEncodableValueException('Document types are not allowed.');
             }
-            if (!$rootNode && \XML_PI_NODE !== $child->nodeType) {
+            if (!$rootNode) {
                 $rootNode = $child;
             }
         }
@@ -164,32 +206,35 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
     /**
      * Sets the root node name.
      *
+     * @deprecated since Symfony 4.2
+     *
      * @param string $name Root node name
      */
     public function setRootNodeName($name)
     {
-        $this->rootNodeName = $name;
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the context instead.', __METHOD__), \E_USER_DEPRECATED);
+
+        $this->defaultContext[self::ROOT_NODE_NAME] = $name;
     }
 
     /**
      * Returns the root node name.
      *
+     * @deprecated since Symfony 4.2
+     *
      * @return string
      */
     public function getRootNodeName()
     {
-        return $this->rootNodeName;
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the context instead.', __METHOD__), \E_USER_DEPRECATED);
+
+        return $this->defaultContext[self::ROOT_NODE_NAME];
     }
 
-    /**
-     * @param string $val
-     *
-     * @return bool
-     */
-    final protected function appendXMLString(\DOMNode $node, $val)
+    final protected function appendXMLString(\DOMNode $node, string $val): bool
     {
-        if (\strlen($val) > 0) {
-            $frag = $this->dom->createDocumentFragment();
+        if ('' !== $val) {
+            $frag = $node->ownerDocument->createDocumentFragment();
             $frag->appendXML($val);
             $node->appendChild($frag);
 
@@ -199,27 +244,17 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         return false;
     }
 
-    /**
-     * @param string $val
-     *
-     * @return bool
-     */
-    final protected function appendText(\DOMNode $node, $val)
+    final protected function appendText(\DOMNode $node, string $val): bool
     {
-        $nodeText = $this->dom->createTextNode($val);
+        $nodeText = $node->ownerDocument->createTextNode($val);
         $node->appendChild($nodeText);
 
         return true;
     }
 
-    /**
-     * @param string $val
-     *
-     * @return bool
-     */
-    final protected function appendCData(\DOMNode $node, $val)
+    final protected function appendCData(\DOMNode $node, string $val): bool
     {
-        $nodeText = $this->dom->createCDATASection($val);
+        $nodeText = $node->ownerDocument->createCDATASection($val);
         $node->appendChild($nodeText);
 
         return true;
@@ -227,10 +262,8 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
 
     /**
      * @param \DOMDocumentFragment $fragment
-     *
-     * @return bool
      */
-    final protected function appendDocumentFragment(\DOMNode $node, $fragment)
+    final protected function appendDocumentFragment(\DOMNode $node, $fragment): bool
     {
         if ($fragment instanceof \DOMDocumentFragment) {
             $node->appendChild($fragment);
@@ -241,17 +274,20 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         return false;
     }
 
+    final protected function appendComment(\DOMNode $node, string $data): bool
+    {
+        $node->appendChild($node->ownerDocument->createComment($data));
+
+        return true;
+    }
+
     /**
      * Checks the name is a valid xml element name.
-     *
-     * @param string $name
-     *
-     * @return bool
      */
-    final protected function isElementNameValid($name)
+    final protected function isElementNameValid(string $name): bool
     {
         return $name &&
-            false === strpos($name, ' ') &&
+            !str_contains($name, ' ') &&
             preg_match('#^[\pL_][\pL0-9._:-]*$#ui', $name);
     }
 
@@ -291,17 +327,15 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
 
     /**
      * Parse the input DOMNode attributes into an array.
-     *
-     * @return array
      */
-    private function parseXmlAttributes(\DOMNode $node, array $context = [])
+    private function parseXmlAttributes(\DOMNode $node, array $context = []): array
     {
         if (!$node->hasAttributes()) {
             return [];
         }
 
         $data = [];
-        $typeCastAttributes = $this->resolveXmlTypeCastAttributes($context);
+        $typeCastAttributes = (bool) ($context[self::TYPE_CAST_ATTRIBUTES] ?? $this->defaultContext[self::TYPE_CAST_ATTRIBUTES]);
 
         foreach ($node->attributes as $attr) {
             if (!is_numeric($attr->nodeValue) || !$typeCastAttributes || (isset($attr->nodeValue[1]) && '0' === $attr->nodeValue[0] && '.' !== $attr->nodeValue[1])) {
@@ -338,27 +372,24 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         }
 
         $value = [];
-
+        $decoderIgnoredNodeTypes = $context[self::DECODER_IGNORED_NODE_TYPES] ?? $this->defaultContext[self::DECODER_IGNORED_NODE_TYPES];
         foreach ($node->childNodes as $subnode) {
-            if (\XML_PI_NODE === $subnode->nodeType) {
+            if (\in_array($subnode->nodeType, $decoderIgnoredNodeTypes, true)) {
                 continue;
             }
 
             $val = $this->parseXml($subnode, $context);
 
             if ('item' === $subnode->nodeName && isset($val['@key'])) {
-                if (isset($val['#'])) {
-                    $value[$val['@key']] = $val['#'];
-                } else {
-                    $value[$val['@key']] = $val;
-                }
+                $value[$val['@key']] = $val['#'] ?? $val;
             } else {
                 $value[$subnode->nodeName][] = $val;
             }
         }
 
+        $asCollection = $context[self::AS_COLLECTION] ?? $this->defaultContext[self::AS_COLLECTION];
         foreach ($value as $key => $val) {
-            if (\is_array($val) && 1 === \count($val)) {
+            if (!$asCollection && \is_array($val) && 1 === \count($val)) {
                 $value[$key] = current($val);
             }
         }
@@ -370,26 +401,32 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
      * Parse the data and convert it to DOMElements.
      *
      * @param array|object $data
-     * @param string|null  $xmlRootNodeName
-     *
-     * @return bool
      *
      * @throws NotEncodableValueException
      */
-    private function buildXml(\DOMNode $parentNode, $data, $xmlRootNodeName = null)
+    private function buildXml(\DOMNode $parentNode, $data, string $format, array $context, string $xmlRootNodeName = null): bool
     {
         $append = true;
+        $removeEmptyTags = $context[self::REMOVE_EMPTY_TAGS] ?? $this->defaultContext[self::REMOVE_EMPTY_TAGS] ?? false;
+        $encoderIgnoredNodeTypes = $context[self::ENCODER_IGNORED_NODE_TYPES] ?? $this->defaultContext[self::ENCODER_IGNORED_NODE_TYPES];
 
-        if (\is_array($data) || ($data instanceof \Traversable && (null === $this->serializer || !$this->serializer->supportsNormalization($data, $this->format)))) {
+        if (\is_array($data) || ($data instanceof \Traversable && (null === $this->serializer || !$this->serializer->supportsNormalization($data, $format)))) {
             foreach ($data as $key => $data) {
-                //Ah this is the magic @ attribute types.
-                if (0 === strpos($key, '@') && $this->isElementNameValid($attributeName = substr($key, 1))) {
-                    if (!is_scalar($data)) {
-                        $data = $this->serializer->normalize($data, $this->format, $this->context);
+                // Ah this is the magic @ attribute types.
+                if (str_starts_with($key, '@') && $this->isElementNameValid($attributeName = substr($key, 1))) {
+                    if (!\is_scalar($data)) {
+                        $data = $this->serializer->normalize($data, $format, $context);
+                    }
+                    if (\is_bool($data)) {
+                        $data = (int) $data;
                     }
                     $parentNode->setAttribute($attributeName, $data);
                 } elseif ('#' === $key) {
-                    $append = $this->selectNodeType($parentNode, $data);
+                    $append = $this->selectNodeType($parentNode, $data, $format, $context);
+                } elseif ('#comment' === $key) {
+                    if (!\in_array(\XML_COMMENT_NODE, $encoderIgnoredNodeTypes, true)) {
+                        $append = $this->appendComment($parentNode, $data);
+                    }
                 } elseif (\is_array($data) && false === is_numeric($key)) {
                     // Is this array fully numeric keys?
                     if (ctype_digit(implode('', array_keys($data)))) {
@@ -399,15 +436,15 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
                          * From ["item" => [0,1]];.
                          */
                         foreach ($data as $subData) {
-                            $append = $this->appendNode($parentNode, $subData, $key);
+                            $append = $this->appendNode($parentNode, $subData, $format, $context, $key);
                         }
                     } else {
-                        $append = $this->appendNode($parentNode, $data, $key);
+                        $append = $this->appendNode($parentNode, $data, $format, $context, $key);
                     }
                 } elseif (is_numeric($key) || !$this->isElementNameValid($key)) {
-                    $append = $this->appendNode($parentNode, $data, 'item', $key);
-                } elseif (null !== $data || !isset($this->context['remove_empty_tags']) || false === $this->context['remove_empty_tags']) {
-                    $append = $this->appendNode($parentNode, $data, $key);
+                    $append = $this->appendNode($parentNode, $data, $format, $context, 'item', $key);
+                } elseif (null !== $data || !$removeEmptyTags) {
+                    $append = $this->appendNode($parentNode, $data, $format, $context, $key);
                 }
             }
 
@@ -419,9 +456,9 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
                 throw new BadMethodCallException(sprintf('The serializer needs to be set to allow "%s()" to be used with object data.', __METHOD__));
             }
 
-            $data = $this->serializer->normalize($data, $this->format, $this->context);
-            if (null !== $data && !is_scalar($data)) {
-                return $this->buildXml($parentNode, $data, $xmlRootNodeName);
+            $data = $this->serializer->normalize($data, $format, $context);
+            if (null !== $data && !\is_scalar($data)) {
+                return $this->buildXml($parentNode, $data, $format, $context, $xmlRootNodeName);
             }
 
             // top level data object was normalized into a scalar
@@ -429,10 +466,10 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
                 $root = $parentNode->parentNode;
                 $root->removeChild($parentNode);
 
-                return $this->appendNode($root, $data, $xmlRootNodeName);
+                return $this->appendNode($root, $data, $format, $context, $xmlRootNodeName);
             }
 
-            return $this->appendNode($parentNode, $data, 'data');
+            return $this->appendNode($parentNode, $data, $format, $context, 'data');
         }
 
         throw new NotEncodableValueException('An unexpected value could not be serialized: '.(!\is_resource($data) ? var_export($data, true) : sprintf('%s resource', get_resource_type($data))));
@@ -442,18 +479,15 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
      * Selects the type of node to create and appends it to the parent.
      *
      * @param array|object $data
-     * @param string       $nodeName
-     * @param string       $key
-     *
-     * @return bool
      */
-    private function appendNode(\DOMNode $parentNode, $data, $nodeName, $key = null)
+    private function appendNode(\DOMNode $parentNode, $data, string $format, array $context, string $nodeName, string $key = null): bool
     {
-        $node = $this->dom->createElement($nodeName);
+        $dom = $parentNode instanceof \DOMDocument ? $parentNode : $parentNode->ownerDocument;
+        $node = $dom->createElement($nodeName);
         if (null !== $key) {
             $node->setAttribute('key', $key);
         }
-        $appendNode = $this->selectNodeType($node, $data);
+        $appendNode = $this->selectNodeType($node, $data, $format, $context);
         // we may have decided not to append this node, either in error or if its $nodeName is not valid
         if ($appendNode) {
             $parentNode->appendChild($node);
@@ -464,43 +498,35 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
 
     /**
      * Checks if a value contains any characters which would require CDATA wrapping.
-     *
-     * @param string $val
-     *
-     * @return bool
      */
-    private function needsCdataWrapping($val)
+    private function needsCdataWrapping(string $val): bool
     {
-        return 0 < preg_match('/[<>&]/', $val);
+        return preg_match('/[<>&]/', $val);
     }
 
     /**
      * Tests the value being passed and decide what sort of element to create.
      *
-     * @param mixed $val
-     *
-     * @return bool
-     *
      * @throws NotEncodableValueException
      */
-    private function selectNodeType(\DOMNode $node, $val)
+    private function selectNodeType(\DOMNode $node, $val, string $format, array $context): bool
     {
         if (\is_array($val)) {
-            return $this->buildXml($node, $val);
+            return $this->buildXml($node, $val, $format, $context);
         } elseif ($val instanceof \SimpleXMLElement) {
-            $child = $this->dom->importNode(dom_import_simplexml($val), true);
+            $child = $node->ownerDocument->importNode(dom_import_simplexml($val), true);
             $node->appendChild($child);
         } elseif ($val instanceof \Traversable) {
-            $this->buildXml($node, $val);
+            $this->buildXml($node, $val, $format, $context);
         } elseif ($val instanceof \DOMNode) {
-            $child = $this->dom->importNode($val, true);
+            $child = $node->ownerDocument->importNode($val, true);
             $node->appendChild($child);
         } elseif (\is_object($val)) {
             if (null === $this->serializer) {
                 throw new BadMethodCallException(sprintf('The serializer needs to be set to allow "%s()" to be used with object data.', __METHOD__));
             }
 
-            return $this->selectNodeType($node, $this->serializer->normalize($val, $this->format, $this->context));
+            return $this->selectNodeType($node, $this->serializer->normalize($val, $format, $context), $format, $context);
         } elseif (is_numeric($val)) {
             return $this->appendText($node, (string) $val);
         } elseif (\is_string($val) && $this->needsCdataWrapping($val)) {
@@ -514,55 +540,27 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
         return true;
     }
 
-    /**
-     * Get real XML root node name, taking serializer options into account.
-     *
-     * @return string
-     */
-    private function resolveXmlRootName(array $context = [])
-    {
-        return isset($context['xml_root_node_name'])
-            ? $context['xml_root_node_name']
-            : $this->rootNodeName;
-    }
-
-    /**
-     * Get XML option for type casting attributes Defaults to true.
-     *
-     * @return bool
-     */
-    private function resolveXmlTypeCastAttributes(array $context = [])
-    {
-        return isset($context['xml_type_cast_attributes'])
-            ? (bool) $context['xml_type_cast_attributes']
-            : true;
-    }
-
     /**
      * Create a DOM document, taking serializer options into account.
-     *
-     * @param array $context Options that the encoder has access to
-     *
-     * @return \DOMDocument
      */
-    private function createDomDocument(array $context)
+    private function createDomDocument(array $context): \DOMDocument
     {
         $document = new \DOMDocument();
 
         // Set an attribute on the DOM document specifying, as part of the XML declaration,
         $xmlOptions = [
             // nicely formats output with indentation and extra space
-            'xml_format_output' => 'formatOutput',
+            self::FORMAT_OUTPUT => 'formatOutput',
             // the version number of the document
-            'xml_version' => 'xmlVersion',
+            self::VERSION => 'xmlVersion',
             // the encoding of the document
-            'xml_encoding' => 'encoding',
+            self::ENCODING => 'encoding',
             // whether the document is standalone
-            'xml_standalone' => 'xmlStandalone',
+            self::STANDALONE => 'xmlStandalone',
         ];
         foreach ($xmlOptions as $xmlOption => $documentProperty) {
-            if (isset($context[$xmlOption])) {
-                $document->$documentProperty = $context[$xmlOption];
+            if ($contextOption = $context[$xmlOption] ?? $this->defaultContext[$xmlOption] ?? false) {
+                $document->$documentProperty = $contextOption;
             }
         }
 

vendor/symfony/serializer/Encoder/YamlEncoder.php

@@ -14,6 +14,7 @@ namespace Symfony\Component\Serializer\Encoder;
 use Symfony\Component\Serializer\Exception\RuntimeException;
 use Symfony\Component\Yaml\Dumper;
 use Symfony\Component\Yaml\Parser;
+use Symfony\Component\Yaml\Yaml;
 
 /**
  * Encodes YAML data.
@@ -22,7 +23,10 @@ use Symfony\Component\Yaml\Parser;
  */
 class YamlEncoder implements EncoderInterface, DecoderInterface
 {
-    const FORMAT = 'yaml';
+    public const FORMAT = 'yaml';
+    private const ALTERNATIVE_FORMAT = 'yml';
+
+    public const PRESERVE_EMPTY_OBJECTS = 'preserve_empty_objects';
 
     private $dumper;
     private $parser;
@@ -34,8 +38,8 @@ class YamlEncoder implements EncoderInterface, DecoderInterface
             throw new RuntimeException('The YamlEncoder class requires the "Yaml" component. Install "symfony/yaml" to use it.');
         }
 
-        $this->dumper = $dumper ?: new Dumper();
-        $this->parser = $parser ?: new Parser();
+        $this->dumper = $dumper ?? new Dumper();
+        $this->parser = $parser ?? new Parser();
         $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
     }
 
@@ -46,6 +50,10 @@ class YamlEncoder implements EncoderInterface, DecoderInterface
     {
         $context = array_merge($this->defaultContext, $context);
 
+        if (isset($context[self::PRESERVE_EMPTY_OBJECTS])) {
+            $context['yaml_flags'] |= Yaml::DUMP_OBJECT_AS_MAP;
+        }
+
         return $this->dumper->dump($data, $context['yaml_inline'], $context['yaml_indent'], $context['yaml_flags']);
     }
 
@@ -54,7 +62,7 @@ class YamlEncoder implements EncoderInterface, DecoderInterface
      */
     public function supportsEncoding($format)
     {
-        return self::FORMAT === $format;
+        return self::FORMAT === $format || self::ALTERNATIVE_FORMAT === $format;
     }
 
     /**
@@ -72,6 +80,6 @@ class YamlEncoder implements EncoderInterface, DecoderInterface
      */
     public function supportsDecoding($format)
     {
-        return self::FORMAT === $format;
+        return self::FORMAT === $format || self::ALTERNATIVE_FORMAT === $format;
     }
 }