Add native types to class properties, by Rector PHP

```bash
./rector.phar process src --config=rector.php
```

config:

```php
<?php

declare(strict_types=1);

use Rector\Core\Configuration\Option;
use Rector\Core\ValueObject\PhpVersionFeature;
use Rector\Php74\Rector\Property\TypedPropertyRector;
use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;

return static function (ContainerConfigurator $containerConfigurator): void {
    $services = $containerConfigurator->services();

    $services->set(TypedPropertyRector::class);

        $parameters = $containerConfigurator->parameters();

        $parameters->set(Option::PHP_VERSION_FEATURES, PhpVersionFeature::TYPED_PROPERTIES);
};
```

src/Command/BaseCommand.php

@@ -47,10 +47,7 @@
  */
 abstract class BaseCommand extends Command
 {
-    /**
-     * @var IO|null
-     */
-    private $io;
+    private ?IO $io = null;
 
     final public function getApplication(): Application
     {

src/Config/ConsoleHelper.php

@@ -44,7 +44,7 @@
  */
 class ConsoleHelper
 {
-    private $formatterHelper;
+    private FormatterHelper $formatterHelper;
 
     public function __construct(FormatterHelper $formatterHelper)
     {

src/Config/Guesser/PhpUnitPathGuesser.php

@@ -44,7 +44,7 @@ final class PhpUnitPathGuesser
 {
     private const CURRENT_DIR_PATH = '.';
 
-    private $composerJsonContent;
+    private stdClass $composerJsonContent;
 
     public function __construct(stdClass $composerJsonContent)
     {

src/Config/Guesser/SourceDirGuesser.php

@@ -48,7 +48,7 @@
  */
 class SourceDirGuesser
 {
-    private $composerJsonContent;
+    private stdClass $composerJsonContent;
 
     public function __construct(stdClass $composerJsonContent)
     {

src/Config/ValueProvider/ExcludeDirsProvider.php

@@ -55,9 +55,9 @@ final class ExcludeDirsProvider
 {
     public const EXCLUDED_ROOT_DIRS = ['vendor', 'tests', 'test'];
 
-    private $consoleHelper;
-    private $questionHelper;
-    private $filesystem;
+    private ConsoleHelper $consoleHelper;
+    private QuestionHelper $questionHelper;
+    private Filesystem $filesystem;
 
     public function __construct(ConsoleHelper $consoleHelper, QuestionHelper $questionHelper, Filesystem $filesystem)
     {

src/Config/ValueProvider/PhpUnitCustomExecutablePathProvider.php

@@ -55,9 +55,9 @@
  */
 final class PhpUnitCustomExecutablePathProvider
 {
-    private $phpUnitExecutableFinder;
-    private $consoleHelper;
-    private $questionHelper;
+    private TestFrameworkFinder $phpUnitExecutableFinder;
+    private ConsoleHelper $consoleHelper;
+    private QuestionHelper $questionHelper;
 
     public function __construct(TestFrameworkFinder $phpUnitExecutableFinder, ConsoleHelper $consoleHelper, QuestionHelper $questionHelper)
     {

src/Config/ValueProvider/SourceDirsProvider.php

@@ -53,9 +53,9 @@
  */
 final class SourceDirsProvider
 {
-    private $consoleHelper;
-    private $questionHelper;
-    private $sourceDirGuesser;
+    private ConsoleHelper $consoleHelper;
+    private QuestionHelper $questionHelper;
+    private SourceDirGuesser $sourceDirGuesser;
 
     public function __construct(
         ConsoleHelper $consoleHelper,

src/Config/ValueProvider/TestFrameworkConfigPathProvider.php

@@ -55,9 +55,9 @@
  */
 final class TestFrameworkConfigPathProvider
 {
-    private $testFrameworkConfigLocator;
-    private $consoleHelper;
-    private $questionHelper;
+    private TestFrameworkConfigLocatorInterface $testFrameworkConfigLocator;
+    private ConsoleHelper $consoleHelper;
+    private QuestionHelper $questionHelper;
 
     public function __construct(TestFrameworkConfigLocatorInterface $testFrameworkConfigLocator, ConsoleHelper $consoleHelper, QuestionHelper $questionHelper)
     {

src/Config/ValueProvider/TextLogFileProvider.php

@@ -47,8 +47,8 @@ final class TextLogFileProvider
 {
     public const TEXT_LOG_FILE_NAME = 'infection.log';
 
-    private $consoleHelper;
-    private $questionHelper;
+    private ConsoleHelper $consoleHelper;
+    private QuestionHelper $questionHelper;
 
     public function __construct(ConsoleHelper $consoleHelper, QuestionHelper $questionHelper)
     {

src/Configuration/Configuration.php

@@ -54,34 +54,39 @@ class Configuration
         'default',
     ];
 
-    private $timeout;
-    private $sourceDirectories;
-    private $sourceFiles;
-    private $sourceFilesFilter;
-    private $sourceFilesExcludes;
-    private $logs;
-    private $logVerbosity;
-    private $tmpDir;
-    private $phpUnit;
-    private $mutators;
-    private $testFramework;
-    private $bootstrap;
-    private $initialTestsPhpOptions;
-    private $testFrameworkExtraOptions;
-    private $coveragePath;
-    private $skipCoverage;
-    private $skipInitialTests;
-    private $debug;
-    private $onlyCovered;
-    private $noProgress;
-    private $ignoreMsiWithNoMutations;
-    private $minMsi;
-    private $showMutations;
-    private $minCoveredMsi;
-    private $msiPrecision;
-    private $threadCount;
-    private $dryRun;
-    private $ignoreSourceCodeMutatorsMap;
+    private float $timeout;
+    /** @var string[] */
+    private array $sourceDirectories;
+    /** @var iterable<SplFileInfo> */
+    private iterable $sourceFiles;
+    private string $sourceFilesFilter;
+    /** @var string[] */
+    private array $sourceFilesExcludes;
+    private Logs $logs;
+    private string $logVerbosity;
+    private string $tmpDir;
+    private PhpUnit $phpUnit;
+    /** @var array<string, Mutator> */
+    private array $mutators;
+    private string $testFramework;
+    private ?string $bootstrap = null;
+    private ?string $initialTestsPhpOptions = null;
+    private string $testFrameworkExtraOptions;
+    private string $coveragePath;
+    private bool $skipCoverage;
+    private bool $skipInitialTests;
+    private bool $debug;
+    private bool $onlyCovered;
+    private bool $noProgress;
+    private bool $ignoreMsiWithNoMutations;
+    private ?float $minMsi = null;
+    private bool $showMutations;
+    private ?float $minCoveredMsi = null;
+    private int $msiPrecision;
+    private int $threadCount;
+    private bool $dryRun;
+    /** @var array<string, array<int, string>> */
+    private array $ignoreSourceCodeMutatorsMap;
 
     /**
      * @param string[] $sourceDirectories

src/Configuration/ConfigurationFactory.php

@@ -65,12 +65,12 @@ class ConfigurationFactory
      */
     private const DEFAULT_TIMEOUT = 10;
 
-    private $tmpDirProvider;
-    private $mutatorResolver;
-    private $mutatorFactory;
-    private $mutatorParser;
-    private $sourceFileCollector;
-    private $ciDetector;
+    private TmpDirProvider $tmpDirProvider;
+    private MutatorResolver $mutatorResolver;
+    private MutatorFactory $mutatorFactory;
+    private MutatorParser $mutatorParser;
+    private SourceFileCollector $sourceFileCollector;
+    private CiDetector $ciDetector;
 
     public function __construct(
         TmpDirProvider $tmpDirProvider,

src/Configuration/Entry/Badge.php

@@ -40,7 +40,7 @@
  */
 final class Badge
 {
-    private $branch;
+    private string $branch;
 
     public function __construct(string $branch)
     {

src/Configuration/Entry/Logs.php

@@ -40,12 +40,12 @@
  */
 final class Logs
 {
-    private $textLogFilePath;
-    private $summaryLogFilePath;
-    private $jsonLogFilePath;
-    private $debugLogFilePath;
-    private $perMutatorFilePath;
-    private $badge;
+    private ?string $textLogFilePath;
+    private ?string $summaryLogFilePath;
+    private ?string $jsonLogFilePath;
+    private ?string $debugLogFilePath;
+    private ?string $perMutatorFilePath;
+    private ?Badge $badge;
 
     public function __construct(
         ?string $textLogFilePath,

src/Configuration/Entry/PhpUnit.php

@@ -40,8 +40,8 @@
  */
 final class PhpUnit
 {
-    private $configDir;
-    private $customPath;
+    private ?string $configDir;
+    private ?string $customPath;
 
     public function __construct(?string $configDir, ?string $executablePath)
     {

src/Configuration/Entry/Source.php

@@ -42,8 +42,10 @@
  */
 final class Source
 {
-    private $directories;
-    private $excludes;
+    /** @var string[] */
+    private array $directories;
+    /** @var string[] */
+    private array $excludes;
 
     /**
      * @param string[] $directories

src/Configuration/Schema/SchemaConfiguration.php

@@ -46,20 +46,21 @@
  */
 final class SchemaConfiguration
 {
-    private $file;
-    private $timeout;
-    private $source;
-    private $logs;
-    private $tmpDir;
-    private $phpUnit;
-    private $ignoreMsiWithNoMutations;
-    private $minMsi;
-    private $minCoveredMsi;
-    private $mutators;
-    private $testFramework;
-    private $bootstrap;
-    private $initialTestsPhpOptions;
-    private $testFrameworkExtraOptions;
+    private string $file;
+    private ?float $timeout;
+    private Source $source;
+    private Logs $logs;
+    private ?string $tmpDir;
+    private PhpUnit $phpUnit;
+    private ?bool $ignoreMsiWithNoMutations;
+    private ?float $minMsi;
+    private ?float $minCoveredMsi;
+    /** @var array<string, mixed> */
+    private array $mutators;
+    private ?string $testFramework;
+    private ?string $bootstrap;
+    private ?string $initialTestsPhpOptions;
+    private ?string $testFrameworkExtraOptions;
 
     /**
      * @param array<string, mixed> $mutators

src/Configuration/Schema/SchemaConfigurationFile.php

@@ -47,12 +47,9 @@
  */
 final class SchemaConfigurationFile
 {
-    private $path;
+    private string $path;
 
-    /**
-     * @var stdClass|null
-     */
-    private $decodedContents;
+    private ?stdClass $decodedContents = null;
 
     public function __construct(string $path)
     {

src/Configuration/Schema/SchemaConfigurationFileLoader.php

@@ -40,8 +40,8 @@
  */
 class SchemaConfigurationFileLoader
 {
-    private $schemaValidator;
-    private $factory;
+    private SchemaValidator $schemaValidator;
+    private SchemaConfigurationFactory $factory;
 
     public function __construct(SchemaValidator $schemaValidator, SchemaConfigurationFactory $factory)
     {

src/Configuration/Schema/SchemaConfigurationLoader.php

@@ -45,8 +45,8 @@ final class SchemaConfigurationLoader
     public const DEFAULT_DIST_CONFIG_FILE = 'infection.json.dist';
     public const DEFAULT_CONFIG_FILE = 'infection.json';
 
-    private $locator;
-    private $fileLoader;
+    private Locator $locator;
+    private SchemaConfigurationFileLoader $fileLoader;
 
     public function __construct(Locator $locator, SchemaConfigurationFileLoader $fileLoader)
     {

src/Console/Application.php

@@ -67,7 +67,7 @@ final class Application extends BaseApplication
 
 ';
 
-    private $container;
+    private Container $container;
 
     public function __construct(Container $container)
     {

src/Console/ConsoleOutput.php

@@ -49,7 +49,7 @@ class ConsoleOutput
     private const RUNNING_WITH_DEBUGGER_NOTE = 'You are running Infection with %s enabled.';
     private const MIN_MSI_CAN_GET_INCREASED_NOTICE = 'The %s is %s%% percentage points over the required %s. Consider increasing the required %s percentage the next time you run Infection.';
 
-    private $logger;
+    private ConsoleLogger $logger;
 
     public function __construct(ConsoleLogger $logger)
     {

src/Console/IO.php

@@ -46,8 +46,8 @@
  */
 final class IO extends SymfonyStyle
 {
-    private $input;
-    private $output;
+    private InputInterface $input;
+    private OutputInterface $output;
 
     public function __construct(InputInterface $input, OutputInterface $output)
     {

src/Console/OutputFormatter/AbstractOutputFormatter.php

@@ -49,10 +49,7 @@ abstract class AbstractOutputFormatter implements OutputFormatter
      */
     public const UNKNOWN_COUNT = 0;
 
-    /**
-     * @var int
-     */
-    protected $callsCount = 0;
+    protected int $callsCount = 0;
 
     public function start(int $mutationCount): void
     {

src/Console/OutputFormatter/DotFormatter.php

@@ -49,7 +49,7 @@ final class DotFormatter extends AbstractOutputFormatter
 {
     private const DOTS_PER_ROW = 50;
 
-    private $output;
+    private OutputInterface $output;
 
     public function __construct(OutputInterface $output)
     {

src/Console/OutputFormatter/FormatterFactory.php

@@ -47,7 +47,7 @@
  */
 final class FormatterFactory
 {
-    private $output;
+    private OutputInterface $output;
 
     public function __construct(OutputInterface $output)
     {

src/Console/OutputFormatter/ProgressFormatter.php

@@ -43,7 +43,7 @@
  */
 final class ProgressFormatter extends AbstractOutputFormatter
 {
-    private $progressBar;
+    private ProgressBar $progressBar;
 
     public function __construct(ProgressBar $progressBar)
     {