Merge branch '4.4' into 5.1

* 4.4:
  [VarDumper] Fix display of nullable union return types.
  [VarDumper] fixed displaying "mixed" as "?mixed"
  Handle failure when sending DATA

src/Symfony/Component/Mailer/Tests/Transport/Smtp/SmtpTransportTest.php

@@ -18,6 +18,8 @@ use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
 use Symfony\Component\Mailer\Transport\Smtp\Stream\AbstractStream;
 use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
 use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\Email;
+use Symfony\Component\Mime\Exception\InvalidArgumentException;
 use Symfony\Component\Mime\RawMessage;
 
 class SmtpTransportTest extends TestCase
@@ -86,6 +88,29 @@ class SmtpTransportTest extends TestCase
         $transport->send(new RawMessage('Message 3'), $envelope);
         $this->assertContains("NOOP\r\n", $stream->getCommands());
     }
+
+    public function testSendInvalidMessage()
+    {
+        $stream = new DummyStream();
+
+        $transport = new SmtpTransport($stream);
+        $transport->setPingThreshold(1);
+
+        $message = new Email();
+        $message->to('recipient@example.org');
+        $message->from('sender@example.org');
+        $message->attachFromPath('/does_not_exists');
+
+        try {
+            $transport->send($message);
+            $this->fail('Expected Symfony\Component\Mime\Exception\InvalidArgumentException to be thrown');
+        } catch (InvalidArgumentException $e) {
+            $this->assertMatchesRegularExpression('{Path "/does_not_exists"}i', $e->getMessage());
+        }
+
+        $this->assertNotContains("\r\n.\r\n", $stream->getCommands());
+        $this->assertTrue($stream->isClosed());
+    }
 }
 
 class DummyStream extends AbstractStream
@@ -164,4 +189,10 @@ class DummyStream extends AbstractStream
     {
         return $this->closed;
     }
+
+    public function terminate(): void
+    {
+        parent::terminate();
+        $this->closed = true;
+    }
 }

src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php

@@ -159,7 +159,7 @@ class SmtpTransport extends AbstractTransport
             return $name;
         }
 
-        return sprintf('smtp://sendmail');
+        return 'smtp://sendmail';
     }
 
     /**
@@ -200,10 +200,19 @@ class SmtpTransport extends AbstractTransport
             }
 
             $this->executeCommand("DATA\r\n", [354]);
-            foreach (AbstractStream::replace("\r\n.", "\r\n..", $message->toIterable()) as $chunk) {
-                $this->stream->write($chunk, false);
+            try {
+                foreach (AbstractStream::replace("\r\n.", "\r\n..", $message->toIterable()) as $chunk) {
+                    $this->stream->write($chunk, false);
+                }
+                $this->stream->flush();
+            } catch (TransportExceptionInterface $e) {
+                throw $e;
+            } catch (\Exception $e) {
+                $this->stream->terminate();
+                $this->started = false;
+                $this->getLogger()->debug(sprintf('Email transport "%s" stopped', __CLASS__));
+                throw $e;
             }
-            $this->stream->flush();
             $this->executeCommand("\r\n.\r\n", [250]);
             $message->appendDebug($this->stream->getDebug());
             $this->lastMessageTime = microtime(true);

src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php

@@ -183,7 +183,7 @@ class ReflectionCaster
         if (isset($a[$prefix.'returnType'])) {
             $v = $a[$prefix.'returnType'];
             $v = $v instanceof \ReflectionNamedType ? $v->getName() : (string) $v;
-            $a[$prefix.'returnType'] = new ClassStub($a[$prefix.'returnType']->allowsNull() ? '?'.$v : $v, [class_exists($v, false) || interface_exists($v, false) || trait_exists($v, false) ? $v : '', '']);
+            $a[$prefix.'returnType'] = new ClassStub($a[$prefix.'returnType'] instanceof \ReflectionNamedType && $a[$prefix.'returnType']->allowsNull() && 'mixed' !== $v ? '?'.$v : $v, [class_exists($v, false) || interface_exists($v, false) || trait_exists($v, false) ? $v : '', '']);
         }
         if (isset($a[$prefix.'class'])) {
             $a[$prefix.'class'] = new ClassStub($a[$prefix.'class']);
@@ -323,7 +323,7 @@ class ReflectionCaster
                     if (!$type instanceof \ReflectionNamedType) {
                         $signature .= $type.' ';
                     } else {
-                        if (!$param->isOptional() && $param->allowsNull()) {
+                        if (!$param->isOptional() && $param->allowsNull() && 'mixed' !== $type->getName()) {
                             $signature .= '?';
                         }
                         $signature .= substr(strrchr('\\'.$type->getName(), '\\'), 1).' ';

src/Symfony/Component/VarDumper/Tests/Caster/ReflectionCasterTest.php

@@ -149,6 +149,68 @@ EOTXT
         );
     }
 
+    /**
+     * @requires PHP 8
+     */
+    public function testReflectionParameterMixed()
+    {
+        $f = eval('return function (mixed $a) {};');
+        $var = new \ReflectionParameter($f, 0);
+
+        $this->assertDumpMatchesFormat(
+            <<<'EOTXT'
+ReflectionParameter {
+  +name: "a"
+  position: 0
+  allowsNull: true
+  typeHint: "mixed"
+}
+EOTXT
+            , $var
+        );
+    }
+
+    /**
+     * @requires PHP 8
+     */
+    public function testReflectionParameterUnion()
+    {
+        $f = eval('return function (int|float $a) {};');
+        $var = new \ReflectionParameter($f, 0);
+
+        $this->assertDumpMatchesFormat(
+            <<<'EOTXT'
+ReflectionParameter {
+  +name: "a"
+  position: 0
+  typeHint: "int|float"
+}
+EOTXT
+            , $var
+        );
+    }
+
+    /**
+     * @requires PHP 8
+     */
+    public function testReflectionParameterNullableUnion()
+    {
+        $f = eval('return function (int|float|null $a) {};');
+        $var = new \ReflectionParameter($f, 0);
+
+        $this->assertDumpMatchesFormat(
+            <<<'EOTXT'
+ReflectionParameter {
+  +name: "a"
+  position: 0
+  allowsNull: true
+  typeHint: "int|float|null"
+}
+EOTXT
+            , $var
+        );
+    }
+
     public function testReturnType()
     {
         $f = eval('return function ():int {};');
@@ -168,6 +230,72 @@ EOTXT
         );
     }
 
+    /**
+     * @requires PHP 8
+     */
+    public function testMixedReturnType()
+    {
+        $f = eval('return function (): mixed {};');
+        $line = __LINE__ - 1;
+
+        $this->assertDumpMatchesFormat(
+            <<<EOTXT
+Closure(): mixed {
+  returnType: "mixed"
+  class: "Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest"
+  this: Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest { …}
+  file: "%sReflectionCasterTest.php($line) : eval()'d code"
+  line: "1 to 1"
+}
+EOTXT
+            , $f
+        );
+    }
+
+    /**
+     * @requires PHP 8
+     */
+    public function testUnionReturnType()
+    {
+        $f = eval('return function (): int|float {};');
+        $line = __LINE__ - 1;
+
+        $this->assertDumpMatchesFormat(
+            <<<EOTXT
+Closure(): int|float {
+  returnType: "int|float"
+  class: "Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest"
+  this: Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest { …}
+  file: "%sReflectionCasterTest.php($line) : eval()'d code"
+  line: "1 to 1"
+}
+EOTXT
+            , $f
+        );
+    }
+
+    /**
+     * @requires PHP 8
+     */
+    public function testNullableUnionReturnType()
+    {
+        $f = eval('return function (): int|float|null {};');
+        $line = __LINE__ - 1;
+
+        $this->assertDumpMatchesFormat(
+            <<<EOTXT
+Closure(): int|float|null {
+  returnType: "int|float|null"
+  class: "Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest"
+  this: Symfony\Component\VarDumper\Tests\Caster\ReflectionCasterTest { …}
+  file: "%sReflectionCasterTest.php($line) : eval()'d code"
+  line: "1 to 1"
+}
+EOTXT
+            , $f
+        );
+    }
+
     public function testGenerator()
     {
         if (\extension_loaded('xdebug')) {