symfony · nicolas-grekas · Aug 14, 2025 · Aug 14, 2025
diff --git a/UPGRADE-7.4.md b/UPGRADE-7.4.md
@@ -71,6 +71,11 @@ Serializer
 
  * Make `AttributeMetadata` and `ClassMetadata` final
 
+String
+------
+
+ * Deprecate implementing `__sleep/wakeup()` on string implementations
+
 Translation
 -----------
 

diff --git a/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php
@@ -108,24 +108,30 @@ public function __serialize(): array
 
     public function __unserialize(array $data): void
     {
-        if (self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
+        if ($wakeup = self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
             trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
         }
 
         if (\in_array(array_keys($data), [['data'], ["\0*\0data"]], true)) {
             $this->data = $data['data'] ?? $data["\0*\0data"];
 
+            if ($wakeup) {
+                $this->__wakeup();
+            }
+
             return;
         }
 
         trigger_deprecation('symfony/http-kernel', '7.4', 'Passing more than just key "data" to "%s::__unserialize()" is deprecated, populate properties in "%s::__unserialize()" instead.', self::class, get_debug_type($this));
 
-        \Closure::bind(function ($data) {
+        \Closure::bind(function ($data) use ($wakeup) {
             foreach ($data as $key => $value) {
                 $this->{("\0" === $key[0] ?? '') ? substr($key, 1 + strrpos($key, "\0")) : $key} = $value;
             }
 
-            $this->__wakeup();
+            if ($wakeup) {
+                $this->__wakeup();
+            }
         }, $this, static::class)($data);
     }
 
@@ -136,6 +142,8 @@ public function __unserialize(array $data): void
      */
     public function __sleep(): array
     {
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Calling "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
         return ['data'];
     }
 
@@ -146,6 +154,7 @@ public function __sleep(): array
      */
     public function __wakeup(): void
     {
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Calling "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
     }
 
     /**

diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -802,25 +802,46 @@ public function __serialize(): array
 
     public function __unserialize(array $data): void
     {
-        if (self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
+        if ($wakeup = self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
             trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
         }
 
         if (\in_array(array_keys($data), [['environment', 'debug'], ["\0*\0environment", "\0*\0debug"]], true)) {
-            $this->environment = $data['environment'] ?? $data["\0*\0environment"];
-            $this->debug = $data['debug'] ?? $data["\0*\0debug"];
+            $environment = $data['environment'] ?? $data["\0*\0environment"];
+            $debug = $data['debug'] ?? $data["\0*\0debug"];
+
+            if (\is_object($environment) || \is_object($debug)) {
+                throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+            }
+
+            $this->environment = $environment;
+            $this->debug = $debug;
+
+            if ($wakeup) {
+                $this->__wakeup();
+            } else {
+                $this->__construct($environment, $debug);
+            }
 
             return;
         }
 
         trigger_deprecation('symfony/http-kernel', '7.4', 'Passing more than just key "environment" and "debug" to "%s::__unserialize()" is deprecated, populate properties in "%s::__unserialize()" instead.', self::class, get_debug_type($this));
 
-        \Closure::bind(function ($data) {
+        \Closure::bind(function ($data) use ($wakeup) {
             foreach ($data as $key => $value) {
                 $this->{("\0" === $key[0] ?? '') ? substr($key, 1 + strrpos($key, "\0")) : $key} = $value;
             }
 
-            $this->__wakeup();
+            if ($wakeup) {
+                $this->__wakeup();
+            } else {
+                if (\is_object($this->environment) || \is_object($this->debug)) {
+                    throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+                }
+
+                $this->__construct($this->environment, $this->debug);
+            }
         }, $this, static::class)($data);
     }
 
@@ -831,6 +852,8 @@ public function __unserialize(array $data): void
      */
     public function __sleep(): array
     {
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Calling "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
         return ['environment', 'debug'];
     }
 
@@ -841,6 +864,8 @@ public function __sleep(): array
      */
     public function __wakeup(): void
     {
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Calling "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
+
         if (\is_object($this->environment) || \is_object($this->debug)) {
             throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
         }

@@ -219,7 +219,7 @@ public function merge(AttributeMetadataInterface $attributeMetadata): void
     /**
      * @internal since Symfony 7.4, will be replaced by `__serialize()` in 8.0
      *
-     * @final since Symfony 7.4
+     * @final since Symfony 7.4, will be replaced by `__serialize()` in 8.0
      */
     public function __sleep(): array
     {

@@ -96,7 +96,7 @@ public function setClassDiscriminatorMapping(?ClassDiscriminatorMapping $mapping
     /**
      * @internal since Symfony 7.4, will be replaced by `__serialize()` in 8.0
      *
-     * @final since Symfony 7.4
+     * @final since Symfony 7.4, will be replaced by `__serialize()` in 8.0
      */
     public function __sleep(): array
     {

diff --git a/src/Symfony/Component/String/AbstractString.php b/src/Symfony/Component/String/AbstractString.php
@@ -706,8 +706,37 @@ public function wordwrap(int $width = 75, string $break = "\n", bool $cut = fals
         return $str;
     }
 
+    public function __serialize(): array
+    {
+        if (self::class === (new \ReflectionMethod($this, '__sleep'))->class) {
+            return ['string' => $this->string];
+        }
+
+        trigger_deprecation('symfony/string', '7.4', 'Implementing "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
+        $data = [];
+        foreach ($this->__sleep() as $key) {
+            try {
+                if (($r = new \ReflectionProperty($this, $key))->isInitialized($this)) {
+                    $data[$key] = $r->getValue($this);
+                }
+            } catch (\ReflectionException) {
+                $data[$key] = $this->$key;
+            }
+        }
+
+        return $data;
+    }
+
+    /**
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
+     */
     public function __sleep(): array
     {
+        trigger_deprecation('symfony/string', '7.4', 'Calling "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
         return ['string'];
     }
 

diff --git a/src/Symfony/Component/String/CHANGELOG.md b/src/Symfony/Component/String/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+7.4
+---
+
+ * Deprecate implementing `__sleep/wakeup()` on string implementations
+
 7.3
 ---
 

diff --git a/src/Symfony/Component/String/LazyString.php b/src/Symfony/Component/String/LazyString.php
@@ -101,6 +101,35 @@ public function __toString(): string
         }
     }
 
+    public function __serialize(): array
+    {
+        if (self::class === (new \ReflectionMethod($this, '__sleep'))->class) {
+            $this->__toString();
+
+            return ['value' => $this->value];
+        }
+
+        trigger_deprecation('symfony/string', '7.4', 'Implementing "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
+        $data = [];
+        foreach ($this->__sleep() as $key) {
+            try {
+                if (($r = new \ReflectionProperty($this, $key))->isInitialized($this)) {
+                    $data[$key] = $r->getValue($this);
+                }
+            } catch (\ReflectionException) {
+                $data[$key] = $this->$key;
+            }
+        }
+
+        return $data;
+    }
+
+    /**
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
+     */
     public function __sleep(): array
     {
         $this->__toString();

diff --git a/src/Symfony/Component/String/UnicodeString.php b/src/Symfony/Component/String/UnicodeString.php
@@ -366,8 +366,54 @@
         return $prefix === $grapheme;
     }
 
+    public function __unserialize(array $data): void
+    {
+        if ($wakeup = self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
+            trigger_deprecation('symfony/string', '7.4', 'Implementing "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
+        }
+
+        try {
+            if (\in_array(array_keys($data), [['string'], ["\0*\0string"]], true)) {
+                $this->string = $data['string'] ?? $data["\0*\0string"];
+
+                if ($wakeup) {
+                    $this->__wakeup();
+                }
+
+                return;
+            }
+
+            trigger_deprecation('symfony/string', '7.4', 'Passing more than just key "string" to "%s::__unserialize()" is deprecated, populate properties in "%s::__unserialize()" instead.', self::class, get_debug_type($this));
+
+            \Closure::bind(function ($data) use ($wakeup) {
+                foreach ($data as $key => $value) {
+                    $this->{("\0" === $key[0] ?? '') ? substr($key, 1 + strrpos($key, "\0")) : $key} = $value;
+                }
+
+                if ($wakeup) {
+                    $this->__wakeup();
+                }
+            }, $this, static::class)($data);
+        } finally {
+            if (!$wakeup) {
+                if (!\is_string($this->string)) {
+                    throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+                }
+
+                normalizer_is_normalized($this->string) ?: $this->string = normalizer_normalize($this->string);
+            }
+        }
+    }
+
+    /**
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
+     */
     public function __wakeup(): void
     {
+        trigger_deprecation('symfony/string', '7.4', 'Calling "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
+
         if (!\is_string($this->string)) {
             throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
         }

diff --git a/src/Symfony/Component/String/composer.json b/src/Symfony/Component/String/composer.json
@@ -17,6 +17,7 @@
     ],
     "require": {
         "php": ">=8.2",
+        "symfony/deprecation-contracts": "^2.5|^3.0",
         "symfony/polyfill-ctype": "~1.8",
         "symfony/polyfill-intl-grapheme": "~1.33",
         "symfony/polyfill-intl-normalizer": "~1.0",
-Original file line number
+Diff line change
@@ Expand Up / @@ -71,6 +71,11 @@ Serializer @@
      * Make `AttributeMetadata` and `ClassMetadata` final
+    String
+    ------
+     * Deprecate implementing `__sleep/wakeup()` on string implementations
     Translation
     -----------
@@ Expand Down @@